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Fitness for Life: Middle School
by Charles B. Corbin, Guy C. Le Masurier and Dolly D. Lambdin
208 Pages
A winner of the Texty Award for textbook excellence with its first edition, Fitness for Life: Middle School is even stronger in its second edition.
Fitness for Life: Middle School is thoroughly updated to address the new national physical education standards, physical activity guidelines, FITT formulas, and USDA nutrition guidelines. In addition, it is greatly expanded and offers plenty of new material:
- New material on coordinated school health, nutrition, skills, and safety (making the book easy to use in schools with combined PE/health classes)
- New integration of fitness concepts into math, science, and language arts
- New technology sections that engage students in applying technology to their fitness
- A new student interactive web textbook
- A new teacher online bundle
New Interactive Web Texts Offer Great Benefits
The student interactive web textbook contains the same content as the print book but uses interactive audio, video, worksheets and other great activities to help students engage with the material and enhance learning. The interactive web textbook offers audio vocabulary and definitions in English and Spanish. Introductory videos at the beginning of each lesson help students assess their knowledge going in, while videos at the end of each lesson help students put what they’ve learned into context.
(The interactive web text is available to schools that adopt the hardcover student textbook, or as a stand-alone product. Please contact your Human Kinetics K-12 sales representative for details or to request a price quote.)
The teacher online bundle provides teachers with all the materials they need to teach the course—lesson plans, worksheets, rubrics, quizzes, slides, newsletters, and other supporting resources. Teachers can easily access the materials on their computers, laptops, or mobile devices, and they can print whatever they need for use in the classroom or in activities.
Loose-Leaf Packs Available
Teachers also have the option of purchasing binder-ready resources. This loose-leaf pack includes all the resources from the teacher web text except the slides and the test bank. The loose-leaf pack allows teachers to have all the printable resources already printed for them on hole-punched paper, ready to be put in a binder in any order they choose. They can even leave some material out and add materials of their own.
Flexible in Its Application
Fitness for Life: Middle School, Second Edition, is the middle school version of the award-winning Fitness for Life, Sixth Edition. As such, it is a great bridge to the high school program. Teachers can use the units and chapters in a fitness unit, a single-semester class, or a yearlong course, with any configuration of days, in either a gym or a classroom.
One of the only personal fitness textbooks available for middle schoolers, Fitness for Life: Middle School, Second Edition, offers a foundation for students to get physically active and remain active throughout their lives.
Unit I. Fitness and Activity for All
Chapter 1. Introduction to Physical Activity and Fitness
Lesson 1.1: Introduction to Physical Fitness
Lesson 1.2: Introduction to Physical Activity
Chapter Review
Chapter 2. Learning Skills for Enjoying Physical Activity
Lesson 2.1: Learning Motor Skills
Lesson 2.2: The Importance of Practice
Chapter Review
Chapter 3. Moderate Physical Activity
Lesson 3.1: Step 1 of the Physical Activity Pyramid
Lesson 3.2 Benefits of Moderate Physical Activities
Chapter Review
Unit II. Vigorous Aerobics, Sports, Recreation, and Muscle Fitness Exercises
Chapter 4. Vigorous Aerobics
Lesson 4.1: Step 2 of the Physical Activity Pyramid
Lesson 4.2: Benefits of Vigorous Aerobics
Chapter Review
Chapter 5. Vigorous Sports and Recreation
Lesson 5.1: Step 3 of the Physical Activity Pyramid
Lesson 5.2: Benefits of Vigorous Sports and Recreation
Chapter Review
Chapter 6. Muscle Fitness Exercises
Lesson 6.1: Step 4 of the Physical Activity Pyramid
Lesson 6.2: Benefits of Muscle Fitness Exercises
Chapter Review
Unit III. Flexibility, Body Composition, and Planning
Chapter 7. Flexibility Exercises
Lesson 7.1: Step 5 of the Physical Activity Pyramid
Lesson 7.2: Benefits of Flexibility
Chapter Review
Chapter 8. Body Composition, Physical Activity, and Nutrition
Lesson 8.1: Body Composition
Lesson 8.2: Energy Balance: Physical Activity and Nutrition
Chapter Review
Chapter 9. Planning for Physical Activity
Lesson 9.1: Personal Planning: Self-Assessing Fitness and Physical Activity
Lesson 9.2: Personal Planning: Setting Goals, Putting It in Writing, and Reassessing
Chapter Review
Dr. Charles B. (“Chuck”) Corbin, PhD, is a professor emeritus in the school of nutrition and health promotion at Arizona State University. He has published more than 200 journal articles and has authored or coauthored more than 100 books, including Concepts of Physical Fitness, Concepts of Fitness and Wellness, and the Texty Award–winning titles Fitness for Life, Fitness for Life: Middle School, and Fitness for Life: Elementary School. Dr. Corbin is internationally recognized as an expert in physical activity, health, and wellness promotion and youth physical fitness. He has presented keynote addresses at more than 40 state conventions, made major addresses in more than 15 countries, and presented numerous named lectures. He is a past president and emeritus fellow of the National Academy of Kinesiology; a fellow of ACSM, NAKHE, and the North American Society of Health, Physical Education, Recreation and Dance Professionals, and an honor fellow of SHAPE America. His awards include the Healthy American Fitness Leaders Award; the Distinguished Service Award from the President’s Council on Fitness, Sports, and Nutrition (PCFSN); the Luther Halsey Gulick Award, Honor Award, Physical Fitness Council Honor Award, Margie Hanson Award, and Scholar Award from SHAPE America; the Hetherington Award, the highest honor of the National Academy of Kinesiology; and the Lifetime Achievement Award from PCFSN. He received distinguished alumnus awards from the University of New Mexico and the University of Illinois. He was selected to the SHAPE America Hall of Fame. He served for more than 20 years as a member of the advisory board of FitnessGram and was the first chair of the science board of PCFSN.
Guy C. Le Masurier, PhD, is a professor of sport, health, and physical education at Vancouver Island University (British Columbia, Canada). Dr. Le Masurier has published numerous articles related to youth physical activity and physical education, and he has given more than 50 research and professional presentations at national and regional meetings. He is the lead author of Fitness for Life Canada and coauthor of Fitness for Life, Sixth Edition; Health Opportunities Through Physical Education; Fitness for Life: Middle School; and Fitness for Life: Elementary School. Dr. Le Masurier has served as an editorial board member for Research Quarterly for Exercise and Sport and the International Journal of Physical Education, and he reviews research for numerous professional journals. Dr. Le Masurier is a research fellow of SHAPE America. He serves his island community as a volunteer firefighter and loves to grow vegetables.
Dolly D. Lambdin, EdD, is a clinical professor emerita in the department of kinesiology and health education at the University of Texas at Austin. Dr. Lambdin taught K-8 physical education in public and private schools for 16 years and taught preservice teachers and supervised student teachers at the university level for over 40 years. During much of that time, she taught at both levels while also meeting research demands at the university. In addition, Dr. Lambdin served as the president of the National Association for Sport and Physical Education (NASPE) and of SHAPE America. She also served on numerous local, state, and national committees, including the writing teams for the Texas Essential Knowledge and Skills for Physical Educationn, the NASPE Beginning Teacher Standards, and the NASPE Appropriate Practices document. She chaired the measurement advisory panel for SHAPE America’s 50 Million Strong. For more than a decade, Dr. Lambdin has served on the FitnessGram scientific advisory committee. She has been recognized with the NASPE Physical Education Teacher Education Honor Award and NASPE Outstanding Leadership Award. She is a fellow of the North American Society of Health, Physical Education, Recreation and Dance Professionals. Dr. Lambdin is the coauthor of Fitness for Life: Middle School and Fitness for Life: Elementary School, both Texty Award winners, as well as Putting Research to Work in Elementary Physical Education: Conversations in the Gym with Dr. Lawrence F. Locke. Her passion is inspiring teachers to empower their students with the skills, knowledge, habits, and desire to enjoy physical activity and make healthy choices now and for the rest of their lives.
Benjamin A. Sibley, PhD, is an associate professor in the department of recreation management and physical education at Appalachian State University. Dr. Sibley holds degrees in exercise science, physical education, and sport and exercise psychology. He is also an NSCA Certified Strength and Conditioning Specialist and CrossFit Level 2 Trainer. He has been a member of SHAPE America since 2003 and currently serves on the editorial board for the Journal of Physical Education, Recreation and Dance (JOPERD). Dr. Sibley has published and presented numerous papers on physical activity among children and adults, in particular addressing motivation for physical activity and the relationship between physical activity and cognitive performance. In his leisure time, Dr. Sibley enjoys exercising, outdoor activities, cooking, and spending time with his wife and two children.
How Can I Assess My Body Composition?
Body fat is one important component of body composition. Ideally, people shouldn’t have too much or too little body fat. The goal is to be in the healthy fitness zone for your level of body fat.
Body fat is one important component of body composition. Ideally, people shouldn't have too much or too little body fat. The goal is to be in the healthy fitness zone for your level of body fat. The best methods of assessing a person's body fat level involve the use of X-ray machines and special water measurement tanks. These tests are expensive and can't be used quickly, so they aren't practical for general school classes. There are several methods of assessment that are commonly used in schools.
Some schools use a bioelectrical impedance analysis (BIA) machine to assess body fat levels (figure 8.3). Bioelectrical impedance machines have been shown to be quite accurate when used properly. The machine detects differences in water, lean body tissue, and fat, allowing it to estimate the amount of body fat that a person has. Schools that do not have BIA machines can use two other inexpensive methods: body mass index and skinfold measurements.
Figure 8.3 BIA machines can be used to assess body fat levels.
The most common body composition measurement used in schools is called the body mass index (BMI). As described in a special feature later in this lesson, you use your height and weight in a formula to calculate your BMI. The BMI doesn't directly assess body fat levels, but it does help you determine if you are in the healthy fitness zone. The BMI is a test commonly used in FitnessGram.
The BMI uses a formula to determine if you're overweight. The term overweight simply refers to having a BMI (combination of height and weight) that is higher than recommended for good health. Being overweight isn't the same as being high in body fat. It's possible to be high in weight without being too fat, because muscle weighs more than fat. People with a lot of muscle weigh more than people of the same size with less muscle. Even though there are limitations to the BMI, scientists indicate that people with a high BMI have more risk for heart disease, diabetes, and other chronic diseases than people with a BMI in the healthy fitness zone. A person who has an exceptionally high BMI without an exceptionally high amount of muscle or who has an exceptionally high amount of body fat is considered to be obese.
Fit Fact
Overweight in America
Two-thirds of adults and one-third of children and teens are considered to be either overweight or obese, resulting in increased chronic disease risk for many Americans.
Another method of assessing body composition is called skinfold measurements (figure 8.4). As shown in the photo, fat located under the skin is measured using a pair of skinfold calipers. The calipers are used to measure the thickness of fat folds beneath the skin. This test estimates the amount of fat in the body. Skinfold measurements are not as accurate as X-rays and underwater weighing, but they are often used because they give a good estimate of body fat levels and require only a relatively inexpensive pair of calipers and a trained person such as a teacher.
Figure 8.4 Calipers are used to make skinfold measurements.
The results of either the BMI or skinfold measurement tests will help you determine if you are in the healthy fitness zone. Your test results will show if you're in a zone that helps you function effectively and avoid problems associated with having too much or too little body fat or body weight.
Information about your body weight and body composition is personal. In fact, you have the right to treat all fitness testing results as private information. If people ask about your body weight, body composition, or other private information that you're not comfortable sharing, you can make a statement such as, "I don't feel comfortable sharing my personal information. Could you please respect my desire to keep personal information private?"
You should also help others keep their personal information private. For example, don't ask other people about their body weight or body composition. Also, if you work with a partner, keep that person's information private. In chapter 4, you learned some guidelines that you can use to build self-esteem. You may want to review those guidelines at this time.
You can take other steps to keep information confidential. One of the best ways is to share it only with people you trust, and only after asking them to keep the information private. Over time, you can build caring relationships with others, and this will reduce your need to worry about privacy. Sometimes, feeling comfortable in sharing information relieves the pressure of trying to keep things private.
Body Mass Index
Follow these steps and record your results.
- Measure your height in inches or meters without shoes.
- Measure your weight in pounds or kilograms without shoes. If you're wearing street clothes (as opposed to lightweight gym clothing), subtract 2 pounds or 1 kilogram from your weight.
- Use the body mass index chart to determine your BMI. You can also calculate your BMI using either of the following formulas:
BMI = weight in kilograms/(height in meters)2
BMI = weight in pounds/(height in inches)2 × 703
- Use table 8.1 to determine your rating for BMI.
Text adapted from C.B. Corbin and G.C. Le Masurier, 2014, Fitness for life, 6th ed. (Champaign, IL: Human Kinetics), 80.
 |  |
Height/Weight to BMI chart. Locate the row containing your height (left) and column containing your weight (bottom). The value in the box where rows and columns meet is your BMI.
Save
Save
Learn more about Fitness for Life: Middle School, Second Edition.
What Is Physical Activity?
Physical activity occurs when your muscles contract to make your body move. The national physical activity guidelines for teens recommend at least 60 minutes, and up to several hours, of physical activity each day of the week.
Physical activity occurs when your muscles contract to make your body move. The national physical activity guidelines for teens recommend at least 60 minutes, and up to several hours, of physical activity each day of the week. The guidelines recommend that teens perform a variety of activities. There are five basic types of physical activity from which you can choose to meet the national activity recommendation for youth. In this book the Physical Activity Pyramid for Teens is used to illustrate each of the different types of activities (see figure 1.2).
Figure 1.2 The Physical Activity Pyramid for Teens includes many types of activities.
© Charles Corbin
How Do I Know if I Am Active Enough?
In general you are active enough for good health if you meet the national teen guideline of 60 minutes or more of physical activity per day. However, the guidelines indicate that you should do a variety of activities and include some vigorous physical activity and some activity for building muscle fitness and for building strong bones. If you perform a variety of activities from the Physical Activity Pyramid you will meet the national guidelines. In the paragraphs that follow you will learn more about the pyramid.
There is a popular saying that "a picture is worth a thousand words." The saying means remembering a picture may be better than trying to remember a lot of words. So in this book the Physical Activity Pyramid picture is used to help you remember the five types of physical activity. Activities such as moderate physical activity are placed at the wide base of the pyramid because they typically are performed more regularly by people than activities higher in the pyramid. Activities at the bottom typically need to be performed more often than those higher in the pyramid to get benefits. The pyramid also has a triangle at the top that helps you remember the need for energy balance. Energy balance means expending as many calories in physical activity as the calories you consume in food. To get fitness, health, wellness, and energy balance you should choose activities from each of the five steps of the pyramid. You can combine activities from all five steps to meet the daily activity recommendation.
The first step in the pyramid includes moderate physical activities. The intensity of moderate activities is not too easy and not too hard. Any activity that is about as intense as walking briskly is considered moderate. One reason why moderate activities are placed at the bottom of the pyramid is that more people do moderate activity than any other type of activity. Moderate activities are also placed at the wide base of the pyramid because you get the best results when you do them on all or most days of the week. Activities at higher steps in the pyramid can be done less frequently and still provide important benefits.
Many moderate activities are sometimes referred to as lifestyle activities because you do them as part of your daily life. Examples include walking to school, working around the house, and working in the yard. Experts recommend that adults do moderate physical activity for 30 minutes or more each day. This is because activities from step 1 of the Physical Activity Pyramid help people reduce their risk of disease and help them maintain a healthy body weight. Some moderate activities are called lifetime activities because you can do them when you're young as well as when you grow older. Some activities from other steps of the pyramid are also considered to be lifetime activities. Examples include sports such as bowling and golf and recreational activities such as fishing because they're moderate in intensity. As you'll learn later in this book, it's recommended that teens do regular moderate activity to develop activity habits that can be used throughout life.
Vigorous aerobics is included in the second step of the Physical Activity Pyramid. Vigorous aerobics is a type of vigorous physical activity that is especially good for building cardiorespiratory endurance. The word aerobic means "with oxygen." In aerobic activities, your body supplies oxygen to keep you going. When your heart beats faster than normal during vigorous aerobics, your heart supplies your body with the oxygen it needs to keep going. Vigorous aerobics is the most popular type of vigorous physical activity for people of all ages. Examples of vigorous aerobics are running, swimming, in-line skating, aerobic dance, and biking at a vigorous intensity.
Vigorous sports and vigorous recreation at the third step of the pyramid also require your heart to beat faster and require you to breathe faster than normal. When done for at least 20 minutes at a time at least three days a week, these activities build cardiorespiratory endurance and provide health benefits similar to those provided by vigorous aerobics. Examples of vigorous sports are tennis, basketball, badminton, volleyball, and soccer. Examples of vigorous recreation are hiking, backpacking, and biking.
The word vigorous is used in combination with the terms aerobics, sports, and recreation when describing activities at the second and third steps of the pyramid to make it clear that activities at these steps are more intense than moderate activities. Moderate physical activities at the first step of the pyramid are also considered to be aerobic because your body can supply enough oxygen to allow you to keep doing these activities for long periods of time. But they're not considered to be vigorous because they're not intense enough to build optimal levels of cardiorespiratory endurance.
Exercise is a word used to refer to physical activity that is done with the specific purpose of building physical fitness. Muscle fitness exercises are included in the fourth step of the Physical Activity Pyramid for Teens. Muscle fitness exercises are designed to build all three parts of muscle fitness including strength, muscular endurance, and power. One reason why this type of exercise is placed higher in the pyramid than other types is that these exercises need not be performed every day to get benefits. Experts recommend that teens do muscle fitness exercises (such as curl-ups and push-ups) at least two days a week. Muscle fitness exercises help you to build strong bones, prevent muscle injury, and gain many of the same health benefits as with activities from steps 1 through 3.
Flexibility exercises build flexibility and help you to perform well in daily life activities and sport. They may also help reduce risk of injury. They are placed at step 5 of the pyramid. While they can be performed daily, you can maintain flexibility by performing them on two or three days per week.
At the very top of the pyramid is a balance scale. This scale helps show the importance of energy balance. As noted earlier in this lesson, energy balance means that the calories in the food you eat each day are equal to the calories you expend in exercise each day. You must achieve energy balance in order to maintain a healthy body composition. Activities from all steps of the pyramid expend energy and help you balance energy.
At the bottom of the teen physical pyramid are two small pictures with big cross marks over them. One picture is of a video game controller and the other is a picture of a television set. The pictures are meant to caution against being inactive. Being inactive or sedentary isn't good for your health or fitness. It can also limit your productivity in school and in performing other important daily tasks. This does not mean that you should never play video games or watch television. The pictures are meant to indicate that it is good to limit screen time and to avoid being sedentary.
Inactivity, as used in the pyramid, doesn't include productive rest, such as sleep that allows recovery from the day's activities. For example, teens need at least 9 hours of sleep each day. As a teen you also need time for relaxation and productive light activities, such as reading and doing homework.
As noted earlier, to get all of the many benefits of physical activity, teens need to do 60 minutes of daily activity. Ideally you will do activities from each of the five steps each week. You will learn more about the formula for getting optimal benefits in later chapters of this book.
Fit Fact
Do You Sit Too Much?
Many teens spend more time watching TV and playing computer games than they do in school. Each day, you should spend at least as much time in moderate or vigorous activity as you do watching TV or playing inactive games.
Learn more about Fitness for Life: Middle School, Second Edition.
Why Should I Do Vigorous Aerobics?
Vigorous aerobic activities produce many of the same health and wellness benefits of moderate physical activities. One major benefit you get from vigorous aerobics that you can’t get from moderate physical activity is cardiorespiratory endurance.
Vigorous aerobic activities produce many of the same health and wellness benefits of moderate physical activities. One major benefit you get from vigorous aerobics that you can't get from moderate physical activity is cardiorespiratory endurance. In fact, vigorous aerobics is probably the best method of building good cardiorespiratory endurance. As you learned in chapter 1, cardiorespiratory endurance is the ability to perform exercise of your entire body for long periods of time without getting tired. It requires your heart, lungs, blood vessels, and blood to work efficiently and to supply the body with oxygen (figure 4.5). Some of the benefits of doing regular vigorous aerobics are explained in the following paragraphs.
Figure 4.5 Cardiorespiratory endurance requires fitness of many body systems.
Vigorous Aerobics and Cardiorespiratory Endurance for Sports
Teens interested in playing a sport should be very interested in vigorous aerobics because most sports require good cardiorespiratory endurance, and vigorous aerobics is a good way to get it. Sports such as cross-country running, track and field, skiing, swimming, soccer, and tennis are just a few that require cardiorespiratory endurance. You can't perform your best in sports unless you do activities that build good cardiorespiratory endurance.
Vigorous Aerobics and Cardiorespiratory Endurance for Health
Teens who do moderate physical activity get health benefits such as a reduced risk of developing certain diseases. Teens who also do vigorous aerobics get similar benefits and more! Vigorous aerobics can help you get out of the low fitness zone and into the healthy fitness zone for cardiorespiratory endurance.
Vigorous Aerobics and Cardiorespiratory Endurance for Wellness
Vigorous aerobics and the cardiorespiratory endurance that it produces help you to feel and look your best by burning calories and keeping off body fat. You'll feel your best because you'll be less tired. Best of all, you'll have fun because you'll be participating in activities that you enjoy.
Cardiorespiratory Endurance and Safety
In some special cases, people need to run to get help, shovel sand into sandbags, or even shovel snow for long periods of time. Good cardiorespiratory endurance would help a person to perform activities such as these.
Cardiorespiratory Endurance for Work
Certain jobs require cardiorespiratory endurance. For example, to get a job as a member of a fire or police department, you need good cardiorespiratory endurance. Park rangers, lifeguards, construction workers, ranchers, farmers, fitness instructors, and members of the military all must have good cardiorespiratory endurance. Any job that requires you to work for long periods of time and that causes your heart to beat fast requires good cardiorespiratory endurance.
Fit Fact
Blood Flow During Exercise
When you begin exercising, the blood vessels to your exercising muscles expand, and the blood vessels to your stomach and intestines contract. This increases the blood flow to your working muscles.
Firefighters and lifeguards must have good cardiorespiratory endurance.
© iStockphoto/Tim McCaig
Learn more about Fitness for Life: Middle School, Second Edition.
How Can I Assess My Body Composition?
Body fat is one important component of body composition. Ideally, people shouldn’t have too much or too little body fat. The goal is to be in the healthy fitness zone for your level of body fat.
Body fat is one important component of body composition. Ideally, people shouldn't have too much or too little body fat. The goal is to be in the healthy fitness zone for your level of body fat. The best methods of assessing a person's body fat level involve the use of X-ray machines and special water measurement tanks. These tests are expensive and can't be used quickly, so they aren't practical for general school classes. There are several methods of assessment that are commonly used in schools.
Some schools use a bioelectrical impedance analysis (BIA) machine to assess body fat levels (figure 8.3). Bioelectrical impedance machines have been shown to be quite accurate when used properly. The machine detects differences in water, lean body tissue, and fat, allowing it to estimate the amount of body fat that a person has. Schools that do not have BIA machines can use two other inexpensive methods: body mass index and skinfold measurements.
Figure 8.3 BIA machines can be used to assess body fat levels.
The most common body composition measurement used in schools is called the body mass index (BMI). As described in a special feature later in this lesson, you use your height and weight in a formula to calculate your BMI. The BMI doesn't directly assess body fat levels, but it does help you determine if you are in the healthy fitness zone. The BMI is a test commonly used in FitnessGram.
The BMI uses a formula to determine if you're overweight. The term overweight simply refers to having a BMI (combination of height and weight) that is higher than recommended for good health. Being overweight isn't the same as being high in body fat. It's possible to be high in weight without being too fat, because muscle weighs more than fat. People with a lot of muscle weigh more than people of the same size with less muscle. Even though there are limitations to the BMI, scientists indicate that people with a high BMI have more risk for heart disease, diabetes, and other chronic diseases than people with a BMI in the healthy fitness zone. A person who has an exceptionally high BMI without an exceptionally high amount of muscle or who has an exceptionally high amount of body fat is considered to be obese.
Fit Fact
Overweight in America
Two-thirds of adults and one-third of children and teens are considered to be either overweight or obese, resulting in increased chronic disease risk for many Americans.
Another method of assessing body composition is called skinfold measurements (figure 8.4). As shown in the photo, fat located under the skin is measured using a pair of skinfold calipers. The calipers are used to measure the thickness of fat folds beneath the skin. This test estimates the amount of fat in the body. Skinfold measurements are not as accurate as X-rays and underwater weighing, but they are often used because they give a good estimate of body fat levels and require only a relatively inexpensive pair of calipers and a trained person such as a teacher.
Figure 8.4 Calipers are used to make skinfold measurements.
The results of either the BMI or skinfold measurement tests will help you determine if you are in the healthy fitness zone. Your test results will show if you're in a zone that helps you function effectively and avoid problems associated with having too much or too little body fat or body weight.
Information about your body weight and body composition is personal. In fact, you have the right to treat all fitness testing results as private information. If people ask about your body weight, body composition, or other private information that you're not comfortable sharing, you can make a statement such as, "I don't feel comfortable sharing my personal information. Could you please respect my desire to keep personal information private?"
You should also help others keep their personal information private. For example, don't ask other people about their body weight or body composition. Also, if you work with a partner, keep that person's information private. In chapter 4, you learned some guidelines that you can use to build self-esteem. You may want to review those guidelines at this time.
You can take other steps to keep information confidential. One of the best ways is to share it only with people you trust, and only after asking them to keep the information private. Over time, you can build caring relationships with others, and this will reduce your need to worry about privacy. Sometimes, feeling comfortable in sharing information relieves the pressure of trying to keep things private.
Body Mass Index
Follow these steps and record your results.
- Measure your height in inches or meters without shoes.
- Measure your weight in pounds or kilograms without shoes. If you're wearing street clothes (as opposed to lightweight gym clothing), subtract 2 pounds or 1 kilogram from your weight.
- Use the body mass index chart to determine your BMI. You can also calculate your BMI using either of the following formulas:
BMI = weight in kilograms/(height in meters)2
BMI = weight in pounds/(height in inches)2 × 703
- Use table 8.1 to determine your rating for BMI.
Text adapted from C.B. Corbin and G.C. Le Masurier, 2014, Fitness for life, 6th ed. (Champaign, IL: Human Kinetics), 80.
| |
Height/Weight to BMI chart. Locate the row containing your height (left) and column containing your weight (bottom). The value in the box where rows and columns meet is your BMI.
Save
Save
Learn more about Fitness for Life: Middle School, Second Edition.
What Is Physical Activity?
Physical activity occurs when your muscles contract to make your body move. The national physical activity guidelines for teens recommend at least 60 minutes, and up to several hours, of physical activity each day of the week.
Physical activity occurs when your muscles contract to make your body move. The national physical activity guidelines for teens recommend at least 60 minutes, and up to several hours, of physical activity each day of the week. The guidelines recommend that teens perform a variety of activities. There are five basic types of physical activity from which you can choose to meet the national activity recommendation for youth. In this book the Physical Activity Pyramid for Teens is used to illustrate each of the different types of activities (see figure 1.2).
Figure 1.2 The Physical Activity Pyramid for Teens includes many types of activities.
© Charles Corbin
How Do I Know if I Am Active Enough?
In general you are active enough for good health if you meet the national teen guideline of 60 minutes or more of physical activity per day. However, the guidelines indicate that you should do a variety of activities and include some vigorous physical activity and some activity for building muscle fitness and for building strong bones. If you perform a variety of activities from the Physical Activity Pyramid you will meet the national guidelines. In the paragraphs that follow you will learn more about the pyramid.
There is a popular saying that "a picture is worth a thousand words." The saying means remembering a picture may be better than trying to remember a lot of words. So in this book the Physical Activity Pyramid picture is used to help you remember the five types of physical activity. Activities such as moderate physical activity are placed at the wide base of the pyramid because they typically are performed more regularly by people than activities higher in the pyramid. Activities at the bottom typically need to be performed more often than those higher in the pyramid to get benefits. The pyramid also has a triangle at the top that helps you remember the need for energy balance. Energy balance means expending as many calories in physical activity as the calories you consume in food. To get fitness, health, wellness, and energy balance you should choose activities from each of the five steps of the pyramid. You can combine activities from all five steps to meet the daily activity recommendation.
The first step in the pyramid includes moderate physical activities. The intensity of moderate activities is not too easy and not too hard. Any activity that is about as intense as walking briskly is considered moderate. One reason why moderate activities are placed at the bottom of the pyramid is that more people do moderate activity than any other type of activity. Moderate activities are also placed at the wide base of the pyramid because you get the best results when you do them on all or most days of the week. Activities at higher steps in the pyramid can be done less frequently and still provide important benefits.
Many moderate activities are sometimes referred to as lifestyle activities because you do them as part of your daily life. Examples include walking to school, working around the house, and working in the yard. Experts recommend that adults do moderate physical activity for 30 minutes or more each day. This is because activities from step 1 of the Physical Activity Pyramid help people reduce their risk of disease and help them maintain a healthy body weight. Some moderate activities are called lifetime activities because you can do them when you're young as well as when you grow older. Some activities from other steps of the pyramid are also considered to be lifetime activities. Examples include sports such as bowling and golf and recreational activities such as fishing because they're moderate in intensity. As you'll learn later in this book, it's recommended that teens do regular moderate activity to develop activity habits that can be used throughout life.
Vigorous aerobics is included in the second step of the Physical Activity Pyramid. Vigorous aerobics is a type of vigorous physical activity that is especially good for building cardiorespiratory endurance. The word aerobic means "with oxygen." In aerobic activities, your body supplies oxygen to keep you going. When your heart beats faster than normal during vigorous aerobics, your heart supplies your body with the oxygen it needs to keep going. Vigorous aerobics is the most popular type of vigorous physical activity for people of all ages. Examples of vigorous aerobics are running, swimming, in-line skating, aerobic dance, and biking at a vigorous intensity.
Vigorous sports and vigorous recreation at the third step of the pyramid also require your heart to beat faster and require you to breathe faster than normal. When done for at least 20 minutes at a time at least three days a week, these activities build cardiorespiratory endurance and provide health benefits similar to those provided by vigorous aerobics. Examples of vigorous sports are tennis, basketball, badminton, volleyball, and soccer. Examples of vigorous recreation are hiking, backpacking, and biking.
The word vigorous is used in combination with the terms aerobics, sports, and recreation when describing activities at the second and third steps of the pyramid to make it clear that activities at these steps are more intense than moderate activities. Moderate physical activities at the first step of the pyramid are also considered to be aerobic because your body can supply enough oxygen to allow you to keep doing these activities for long periods of time. But they're not considered to be vigorous because they're not intense enough to build optimal levels of cardiorespiratory endurance.
Exercise is a word used to refer to physical activity that is done with the specific purpose of building physical fitness. Muscle fitness exercises are included in the fourth step of the Physical Activity Pyramid for Teens. Muscle fitness exercises are designed to build all three parts of muscle fitness including strength, muscular endurance, and power. One reason why this type of exercise is placed higher in the pyramid than other types is that these exercises need not be performed every day to get benefits. Experts recommend that teens do muscle fitness exercises (such as curl-ups and push-ups) at least two days a week. Muscle fitness exercises help you to build strong bones, prevent muscle injury, and gain many of the same health benefits as with activities from steps 1 through 3.
Flexibility exercises build flexibility and help you to perform well in daily life activities and sport. They may also help reduce risk of injury. They are placed at step 5 of the pyramid. While they can be performed daily, you can maintain flexibility by performing them on two or three days per week.
At the very top of the pyramid is a balance scale. This scale helps show the importance of energy balance. As noted earlier in this lesson, energy balance means that the calories in the food you eat each day are equal to the calories you expend in exercise each day. You must achieve energy balance in order to maintain a healthy body composition. Activities from all steps of the pyramid expend energy and help you balance energy.
At the bottom of the teen physical pyramid are two small pictures with big cross marks over them. One picture is of a video game controller and the other is a picture of a television set. The pictures are meant to caution against being inactive. Being inactive or sedentary isn't good for your health or fitness. It can also limit your productivity in school and in performing other important daily tasks. This does not mean that you should never play video games or watch television. The pictures are meant to indicate that it is good to limit screen time and to avoid being sedentary.
Inactivity, as used in the pyramid, doesn't include productive rest, such as sleep that allows recovery from the day's activities. For example, teens need at least 9 hours of sleep each day. As a teen you also need time for relaxation and productive light activities, such as reading and doing homework.
As noted earlier, to get all of the many benefits of physical activity, teens need to do 60 minutes of daily activity. Ideally you will do activities from each of the five steps each week. You will learn more about the formula for getting optimal benefits in later chapters of this book.
Fit Fact
Do You Sit Too Much?
Many teens spend more time watching TV and playing computer games than they do in school. Each day, you should spend at least as much time in moderate or vigorous activity as you do watching TV or playing inactive games.
Learn more about Fitness for Life: Middle School, Second Edition.
Why Should I Do Vigorous Aerobics?
Vigorous aerobic activities produce many of the same health and wellness benefits of moderate physical activities. One major benefit you get from vigorous aerobics that you can’t get from moderate physical activity is cardiorespiratory endurance.
Vigorous aerobic activities produce many of the same health and wellness benefits of moderate physical activities. One major benefit you get from vigorous aerobics that you can't get from moderate physical activity is cardiorespiratory endurance. In fact, vigorous aerobics is probably the best method of building good cardiorespiratory endurance. As you learned in chapter 1, cardiorespiratory endurance is the ability to perform exercise of your entire body for long periods of time without getting tired. It requires your heart, lungs, blood vessels, and blood to work efficiently and to supply the body with oxygen (figure 4.5). Some of the benefits of doing regular vigorous aerobics are explained in the following paragraphs.
Figure 4.5 Cardiorespiratory endurance requires fitness of many body systems.
Vigorous Aerobics and Cardiorespiratory Endurance for Sports
Teens interested in playing a sport should be very interested in vigorous aerobics because most sports require good cardiorespiratory endurance, and vigorous aerobics is a good way to get it. Sports such as cross-country running, track and field, skiing, swimming, soccer, and tennis are just a few that require cardiorespiratory endurance. You can't perform your best in sports unless you do activities that build good cardiorespiratory endurance.
Vigorous Aerobics and Cardiorespiratory Endurance for Health
Teens who do moderate physical activity get health benefits such as a reduced risk of developing certain diseases. Teens who also do vigorous aerobics get similar benefits and more! Vigorous aerobics can help you get out of the low fitness zone and into the healthy fitness zone for cardiorespiratory endurance.
Vigorous Aerobics and Cardiorespiratory Endurance for Wellness
Vigorous aerobics and the cardiorespiratory endurance that it produces help you to feel and look your best by burning calories and keeping off body fat. You'll feel your best because you'll be less tired. Best of all, you'll have fun because you'll be participating in activities that you enjoy.
Cardiorespiratory Endurance and Safety
In some special cases, people need to run to get help, shovel sand into sandbags, or even shovel snow for long periods of time. Good cardiorespiratory endurance would help a person to perform activities such as these.
Cardiorespiratory Endurance for Work
Certain jobs require cardiorespiratory endurance. For example, to get a job as a member of a fire or police department, you need good cardiorespiratory endurance. Park rangers, lifeguards, construction workers, ranchers, farmers, fitness instructors, and members of the military all must have good cardiorespiratory endurance. Any job that requires you to work for long periods of time and that causes your heart to beat fast requires good cardiorespiratory endurance.
Fit Fact
Blood Flow During Exercise
When you begin exercising, the blood vessels to your exercising muscles expand, and the blood vessels to your stomach and intestines contract. This increases the blood flow to your working muscles.
Firefighters and lifeguards must have good cardiorespiratory endurance.
© iStockphoto/Tim McCaig
Learn more about Fitness for Life: Middle School, Second Edition.
How Can I Assess My Body Composition?
Body fat is one important component of body composition. Ideally, people shouldn’t have too much or too little body fat. The goal is to be in the healthy fitness zone for your level of body fat.
Body fat is one important component of body composition. Ideally, people shouldn't have too much or too little body fat. The goal is to be in the healthy fitness zone for your level of body fat. The best methods of assessing a person's body fat level involve the use of X-ray machines and special water measurement tanks. These tests are expensive and can't be used quickly, so they aren't practical for general school classes. There are several methods of assessment that are commonly used in schools.
Some schools use a bioelectrical impedance analysis (BIA) machine to assess body fat levels (figure 8.3). Bioelectrical impedance machines have been shown to be quite accurate when used properly. The machine detects differences in water, lean body tissue, and fat, allowing it to estimate the amount of body fat that a person has. Schools that do not have BIA machines can use two other inexpensive methods: body mass index and skinfold measurements.
Figure 8.3 BIA machines can be used to assess body fat levels.
The most common body composition measurement used in schools is called the body mass index (BMI). As described in a special feature later in this lesson, you use your height and weight in a formula to calculate your BMI. The BMI doesn't directly assess body fat levels, but it does help you determine if you are in the healthy fitness zone. The BMI is a test commonly used in FitnessGram.
The BMI uses a formula to determine if you're overweight. The term overweight simply refers to having a BMI (combination of height and weight) that is higher than recommended for good health. Being overweight isn't the same as being high in body fat. It's possible to be high in weight without being too fat, because muscle weighs more than fat. People with a lot of muscle weigh more than people of the same size with less muscle. Even though there are limitations to the BMI, scientists indicate that people with a high BMI have more risk for heart disease, diabetes, and other chronic diseases than people with a BMI in the healthy fitness zone. A person who has an exceptionally high BMI without an exceptionally high amount of muscle or who has an exceptionally high amount of body fat is considered to be obese.
Fit Fact
Overweight in America
Two-thirds of adults and one-third of children and teens are considered to be either overweight or obese, resulting in increased chronic disease risk for many Americans.
Another method of assessing body composition is called skinfold measurements (figure 8.4). As shown in the photo, fat located under the skin is measured using a pair of skinfold calipers. The calipers are used to measure the thickness of fat folds beneath the skin. This test estimates the amount of fat in the body. Skinfold measurements are not as accurate as X-rays and underwater weighing, but they are often used because they give a good estimate of body fat levels and require only a relatively inexpensive pair of calipers and a trained person such as a teacher.
Figure 8.4 Calipers are used to make skinfold measurements.
The results of either the BMI or skinfold measurement tests will help you determine if you are in the healthy fitness zone. Your test results will show if you're in a zone that helps you function effectively and avoid problems associated with having too much or too little body fat or body weight.
Information about your body weight and body composition is personal. In fact, you have the right to treat all fitness testing results as private information. If people ask about your body weight, body composition, or other private information that you're not comfortable sharing, you can make a statement such as, "I don't feel comfortable sharing my personal information. Could you please respect my desire to keep personal information private?"
You should also help others keep their personal information private. For example, don't ask other people about their body weight or body composition. Also, if you work with a partner, keep that person's information private. In chapter 4, you learned some guidelines that you can use to build self-esteem. You may want to review those guidelines at this time.
You can take other steps to keep information confidential. One of the best ways is to share it only with people you trust, and only after asking them to keep the information private. Over time, you can build caring relationships with others, and this will reduce your need to worry about privacy. Sometimes, feeling comfortable in sharing information relieves the pressure of trying to keep things private.
Body Mass Index
Follow these steps and record your results.
- Measure your height in inches or meters without shoes.
- Measure your weight in pounds or kilograms without shoes. If you're wearing street clothes (as opposed to lightweight gym clothing), subtract 2 pounds or 1 kilogram from your weight.
- Use the body mass index chart to determine your BMI. You can also calculate your BMI using either of the following formulas:
BMI = weight in kilograms/(height in meters)2
BMI = weight in pounds/(height in inches)2 × 703
- Use table 8.1 to determine your rating for BMI.
Text adapted from C.B. Corbin and G.C. Le Masurier, 2014, Fitness for life, 6th ed. (Champaign, IL: Human Kinetics), 80.
| |
Height/Weight to BMI chart. Locate the row containing your height (left) and column containing your weight (bottom). The value in the box where rows and columns meet is your BMI.
Save
Save
Learn more about Fitness for Life: Middle School, Second Edition.
What Is Physical Activity?
Physical activity occurs when your muscles contract to make your body move. The national physical activity guidelines for teens recommend at least 60 minutes, and up to several hours, of physical activity each day of the week.
Physical activity occurs when your muscles contract to make your body move. The national physical activity guidelines for teens recommend at least 60 minutes, and up to several hours, of physical activity each day of the week. The guidelines recommend that teens perform a variety of activities. There are five basic types of physical activity from which you can choose to meet the national activity recommendation for youth. In this book the Physical Activity Pyramid for Teens is used to illustrate each of the different types of activities (see figure 1.2).
Figure 1.2 The Physical Activity Pyramid for Teens includes many types of activities.
© Charles Corbin
How Do I Know if I Am Active Enough?
In general you are active enough for good health if you meet the national teen guideline of 60 minutes or more of physical activity per day. However, the guidelines indicate that you should do a variety of activities and include some vigorous physical activity and some activity for building muscle fitness and for building strong bones. If you perform a variety of activities from the Physical Activity Pyramid you will meet the national guidelines. In the paragraphs that follow you will learn more about the pyramid.
There is a popular saying that "a picture is worth a thousand words." The saying means remembering a picture may be better than trying to remember a lot of words. So in this book the Physical Activity Pyramid picture is used to help you remember the five types of physical activity. Activities such as moderate physical activity are placed at the wide base of the pyramid because they typically are performed more regularly by people than activities higher in the pyramid. Activities at the bottom typically need to be performed more often than those higher in the pyramid to get benefits. The pyramid also has a triangle at the top that helps you remember the need for energy balance. Energy balance means expending as many calories in physical activity as the calories you consume in food. To get fitness, health, wellness, and energy balance you should choose activities from each of the five steps of the pyramid. You can combine activities from all five steps to meet the daily activity recommendation.
The first step in the pyramid includes moderate physical activities. The intensity of moderate activities is not too easy and not too hard. Any activity that is about as intense as walking briskly is considered moderate. One reason why moderate activities are placed at the bottom of the pyramid is that more people do moderate activity than any other type of activity. Moderate activities are also placed at the wide base of the pyramid because you get the best results when you do them on all or most days of the week. Activities at higher steps in the pyramid can be done less frequently and still provide important benefits.
Many moderate activities are sometimes referred to as lifestyle activities because you do them as part of your daily life. Examples include walking to school, working around the house, and working in the yard. Experts recommend that adults do moderate physical activity for 30 minutes or more each day. This is because activities from step 1 of the Physical Activity Pyramid help people reduce their risk of disease and help them maintain a healthy body weight. Some moderate activities are called lifetime activities because you can do them when you're young as well as when you grow older. Some activities from other steps of the pyramid are also considered to be lifetime activities. Examples include sports such as bowling and golf and recreational activities such as fishing because they're moderate in intensity. As you'll learn later in this book, it's recommended that teens do regular moderate activity to develop activity habits that can be used throughout life.
Vigorous aerobics is included in the second step of the Physical Activity Pyramid. Vigorous aerobics is a type of vigorous physical activity that is especially good for building cardiorespiratory endurance. The word aerobic means "with oxygen." In aerobic activities, your body supplies oxygen to keep you going. When your heart beats faster than normal during vigorous aerobics, your heart supplies your body with the oxygen it needs to keep going. Vigorous aerobics is the most popular type of vigorous physical activity for people of all ages. Examples of vigorous aerobics are running, swimming, in-line skating, aerobic dance, and biking at a vigorous intensity.
Vigorous sports and vigorous recreation at the third step of the pyramid also require your heart to beat faster and require you to breathe faster than normal. When done for at least 20 minutes at a time at least three days a week, these activities build cardiorespiratory endurance and provide health benefits similar to those provided by vigorous aerobics. Examples of vigorous sports are tennis, basketball, badminton, volleyball, and soccer. Examples of vigorous recreation are hiking, backpacking, and biking.
The word vigorous is used in combination with the terms aerobics, sports, and recreation when describing activities at the second and third steps of the pyramid to make it clear that activities at these steps are more intense than moderate activities. Moderate physical activities at the first step of the pyramid are also considered to be aerobic because your body can supply enough oxygen to allow you to keep doing these activities for long periods of time. But they're not considered to be vigorous because they're not intense enough to build optimal levels of cardiorespiratory endurance.
Exercise is a word used to refer to physical activity that is done with the specific purpose of building physical fitness. Muscle fitness exercises are included in the fourth step of the Physical Activity Pyramid for Teens. Muscle fitness exercises are designed to build all three parts of muscle fitness including strength, muscular endurance, and power. One reason why this type of exercise is placed higher in the pyramid than other types is that these exercises need not be performed every day to get benefits. Experts recommend that teens do muscle fitness exercises (such as curl-ups and push-ups) at least two days a week. Muscle fitness exercises help you to build strong bones, prevent muscle injury, and gain many of the same health benefits as with activities from steps 1 through 3.
Flexibility exercises build flexibility and help you to perform well in daily life activities and sport. They may also help reduce risk of injury. They are placed at step 5 of the pyramid. While they can be performed daily, you can maintain flexibility by performing them on two or three days per week.
At the very top of the pyramid is a balance scale. This scale helps show the importance of energy balance. As noted earlier in this lesson, energy balance means that the calories in the food you eat each day are equal to the calories you expend in exercise each day. You must achieve energy balance in order to maintain a healthy body composition. Activities from all steps of the pyramid expend energy and help you balance energy.
At the bottom of the teen physical pyramid are two small pictures with big cross marks over them. One picture is of a video game controller and the other is a picture of a television set. The pictures are meant to caution against being inactive. Being inactive or sedentary isn't good for your health or fitness. It can also limit your productivity in school and in performing other important daily tasks. This does not mean that you should never play video games or watch television. The pictures are meant to indicate that it is good to limit screen time and to avoid being sedentary.
Inactivity, as used in the pyramid, doesn't include productive rest, such as sleep that allows recovery from the day's activities. For example, teens need at least 9 hours of sleep each day. As a teen you also need time for relaxation and productive light activities, such as reading and doing homework.
As noted earlier, to get all of the many benefits of physical activity, teens need to do 60 minutes of daily activity. Ideally you will do activities from each of the five steps each week. You will learn more about the formula for getting optimal benefits in later chapters of this book.
Fit Fact
Do You Sit Too Much?
Many teens spend more time watching TV and playing computer games than they do in school. Each day, you should spend at least as much time in moderate or vigorous activity as you do watching TV or playing inactive games.
Learn more about Fitness for Life: Middle School, Second Edition.
Why Should I Do Vigorous Aerobics?
Vigorous aerobic activities produce many of the same health and wellness benefits of moderate physical activities. One major benefit you get from vigorous aerobics that you can’t get from moderate physical activity is cardiorespiratory endurance.
Vigorous aerobic activities produce many of the same health and wellness benefits of moderate physical activities. One major benefit you get from vigorous aerobics that you can't get from moderate physical activity is cardiorespiratory endurance. In fact, vigorous aerobics is probably the best method of building good cardiorespiratory endurance. As you learned in chapter 1, cardiorespiratory endurance is the ability to perform exercise of your entire body for long periods of time without getting tired. It requires your heart, lungs, blood vessels, and blood to work efficiently and to supply the body with oxygen (figure 4.5). Some of the benefits of doing regular vigorous aerobics are explained in the following paragraphs.
Figure 4.5 Cardiorespiratory endurance requires fitness of many body systems.
Vigorous Aerobics and Cardiorespiratory Endurance for Sports
Teens interested in playing a sport should be very interested in vigorous aerobics because most sports require good cardiorespiratory endurance, and vigorous aerobics is a good way to get it. Sports such as cross-country running, track and field, skiing, swimming, soccer, and tennis are just a few that require cardiorespiratory endurance. You can't perform your best in sports unless you do activities that build good cardiorespiratory endurance.
Vigorous Aerobics and Cardiorespiratory Endurance for Health
Teens who do moderate physical activity get health benefits such as a reduced risk of developing certain diseases. Teens who also do vigorous aerobics get similar benefits and more! Vigorous aerobics can help you get out of the low fitness zone and into the healthy fitness zone for cardiorespiratory endurance.
Vigorous Aerobics and Cardiorespiratory Endurance for Wellness
Vigorous aerobics and the cardiorespiratory endurance that it produces help you to feel and look your best by burning calories and keeping off body fat. You'll feel your best because you'll be less tired. Best of all, you'll have fun because you'll be participating in activities that you enjoy.
Cardiorespiratory Endurance and Safety
In some special cases, people need to run to get help, shovel sand into sandbags, or even shovel snow for long periods of time. Good cardiorespiratory endurance would help a person to perform activities such as these.
Cardiorespiratory Endurance for Work
Certain jobs require cardiorespiratory endurance. For example, to get a job as a member of a fire or police department, you need good cardiorespiratory endurance. Park rangers, lifeguards, construction workers, ranchers, farmers, fitness instructors, and members of the military all must have good cardiorespiratory endurance. Any job that requires you to work for long periods of time and that causes your heart to beat fast requires good cardiorespiratory endurance.
Fit Fact
Blood Flow During Exercise
When you begin exercising, the blood vessels to your exercising muscles expand, and the blood vessels to your stomach and intestines contract. This increases the blood flow to your working muscles.
Firefighters and lifeguards must have good cardiorespiratory endurance.
© iStockphoto/Tim McCaig
Learn more about Fitness for Life: Middle School, Second Edition.
How Can I Assess My Body Composition?
Body fat is one important component of body composition. Ideally, people shouldn’t have too much or too little body fat. The goal is to be in the healthy fitness zone for your level of body fat.
Body fat is one important component of body composition. Ideally, people shouldn't have too much or too little body fat. The goal is to be in the healthy fitness zone for your level of body fat. The best methods of assessing a person's body fat level involve the use of X-ray machines and special water measurement tanks. These tests are expensive and can't be used quickly, so they aren't practical for general school classes. There are several methods of assessment that are commonly used in schools.
Some schools use a bioelectrical impedance analysis (BIA) machine to assess body fat levels (figure 8.3). Bioelectrical impedance machines have been shown to be quite accurate when used properly. The machine detects differences in water, lean body tissue, and fat, allowing it to estimate the amount of body fat that a person has. Schools that do not have BIA machines can use two other inexpensive methods: body mass index and skinfold measurements.
Figure 8.3 BIA machines can be used to assess body fat levels.
The most common body composition measurement used in schools is called the body mass index (BMI). As described in a special feature later in this lesson, you use your height and weight in a formula to calculate your BMI. The BMI doesn't directly assess body fat levels, but it does help you determine if you are in the healthy fitness zone. The BMI is a test commonly used in FitnessGram.
The BMI uses a formula to determine if you're overweight. The term overweight simply refers to having a BMI (combination of height and weight) that is higher than recommended for good health. Being overweight isn't the same as being high in body fat. It's possible to be high in weight without being too fat, because muscle weighs more than fat. People with a lot of muscle weigh more than people of the same size with less muscle. Even though there are limitations to the BMI, scientists indicate that people with a high BMI have more risk for heart disease, diabetes, and other chronic diseases than people with a BMI in the healthy fitness zone. A person who has an exceptionally high BMI without an exceptionally high amount of muscle or who has an exceptionally high amount of body fat is considered to be obese.
Fit Fact
Overweight in America
Two-thirds of adults and one-third of children and teens are considered to be either overweight or obese, resulting in increased chronic disease risk for many Americans.
Another method of assessing body composition is called skinfold measurements (figure 8.4). As shown in the photo, fat located under the skin is measured using a pair of skinfold calipers. The calipers are used to measure the thickness of fat folds beneath the skin. This test estimates the amount of fat in the body. Skinfold measurements are not as accurate as X-rays and underwater weighing, but they are often used because they give a good estimate of body fat levels and require only a relatively inexpensive pair of calipers and a trained person such as a teacher.
Figure 8.4 Calipers are used to make skinfold measurements.
The results of either the BMI or skinfold measurement tests will help you determine if you are in the healthy fitness zone. Your test results will show if you're in a zone that helps you function effectively and avoid problems associated with having too much or too little body fat or body weight.
Information about your body weight and body composition is personal. In fact, you have the right to treat all fitness testing results as private information. If people ask about your body weight, body composition, or other private information that you're not comfortable sharing, you can make a statement such as, "I don't feel comfortable sharing my personal information. Could you please respect my desire to keep personal information private?"
You should also help others keep their personal information private. For example, don't ask other people about their body weight or body composition. Also, if you work with a partner, keep that person's information private. In chapter 4, you learned some guidelines that you can use to build self-esteem. You may want to review those guidelines at this time.
You can take other steps to keep information confidential. One of the best ways is to share it only with people you trust, and only after asking them to keep the information private. Over time, you can build caring relationships with others, and this will reduce your need to worry about privacy. Sometimes, feeling comfortable in sharing information relieves the pressure of trying to keep things private.
Body Mass Index
Follow these steps and record your results.
- Measure your height in inches or meters without shoes.
- Measure your weight in pounds or kilograms without shoes. If you're wearing street clothes (as opposed to lightweight gym clothing), subtract 2 pounds or 1 kilogram from your weight.
- Use the body mass index chart to determine your BMI. You can also calculate your BMI using either of the following formulas:
BMI = weight in kilograms/(height in meters)2
BMI = weight in pounds/(height in inches)2 × 703
- Use table 8.1 to determine your rating for BMI.
Text adapted from C.B. Corbin and G.C. Le Masurier, 2014, Fitness for life, 6th ed. (Champaign, IL: Human Kinetics), 80.
| |
Height/Weight to BMI chart. Locate the row containing your height (left) and column containing your weight (bottom). The value in the box where rows and columns meet is your BMI.
Save
Save
Learn more about Fitness for Life: Middle School, Second Edition.
What Is Physical Activity?
Physical activity occurs when your muscles contract to make your body move. The national physical activity guidelines for teens recommend at least 60 minutes, and up to several hours, of physical activity each day of the week.
Physical activity occurs when your muscles contract to make your body move. The national physical activity guidelines for teens recommend at least 60 minutes, and up to several hours, of physical activity each day of the week. The guidelines recommend that teens perform a variety of activities. There are five basic types of physical activity from which you can choose to meet the national activity recommendation for youth. In this book the Physical Activity Pyramid for Teens is used to illustrate each of the different types of activities (see figure 1.2).
Figure 1.2 The Physical Activity Pyramid for Teens includes many types of activities.
© Charles Corbin
How Do I Know if I Am Active Enough?
In general you are active enough for good health if you meet the national teen guideline of 60 minutes or more of physical activity per day. However, the guidelines indicate that you should do a variety of activities and include some vigorous physical activity and some activity for building muscle fitness and for building strong bones. If you perform a variety of activities from the Physical Activity Pyramid you will meet the national guidelines. In the paragraphs that follow you will learn more about the pyramid.
There is a popular saying that "a picture is worth a thousand words." The saying means remembering a picture may be better than trying to remember a lot of words. So in this book the Physical Activity Pyramid picture is used to help you remember the five types of physical activity. Activities such as moderate physical activity are placed at the wide base of the pyramid because they typically are performed more regularly by people than activities higher in the pyramid. Activities at the bottom typically need to be performed more often than those higher in the pyramid to get benefits. The pyramid also has a triangle at the top that helps you remember the need for energy balance. Energy balance means expending as many calories in physical activity as the calories you consume in food. To get fitness, health, wellness, and energy balance you should choose activities from each of the five steps of the pyramid. You can combine activities from all five steps to meet the daily activity recommendation.
The first step in the pyramid includes moderate physical activities. The intensity of moderate activities is not too easy and not too hard. Any activity that is about as intense as walking briskly is considered moderate. One reason why moderate activities are placed at the bottom of the pyramid is that more people do moderate activity than any other type of activity. Moderate activities are also placed at the wide base of the pyramid because you get the best results when you do them on all or most days of the week. Activities at higher steps in the pyramid can be done less frequently and still provide important benefits.
Many moderate activities are sometimes referred to as lifestyle activities because you do them as part of your daily life. Examples include walking to school, working around the house, and working in the yard. Experts recommend that adults do moderate physical activity for 30 minutes or more each day. This is because activities from step 1 of the Physical Activity Pyramid help people reduce their risk of disease and help them maintain a healthy body weight. Some moderate activities are called lifetime activities because you can do them when you're young as well as when you grow older. Some activities from other steps of the pyramid are also considered to be lifetime activities. Examples include sports such as bowling and golf and recreational activities such as fishing because they're moderate in intensity. As you'll learn later in this book, it's recommended that teens do regular moderate activity to develop activity habits that can be used throughout life.
Vigorous aerobics is included in the second step of the Physical Activity Pyramid. Vigorous aerobics is a type of vigorous physical activity that is especially good for building cardiorespiratory endurance. The word aerobic means "with oxygen." In aerobic activities, your body supplies oxygen to keep you going. When your heart beats faster than normal during vigorous aerobics, your heart supplies your body with the oxygen it needs to keep going. Vigorous aerobics is the most popular type of vigorous physical activity for people of all ages. Examples of vigorous aerobics are running, swimming, in-line skating, aerobic dance, and biking at a vigorous intensity.
Vigorous sports and vigorous recreation at the third step of the pyramid also require your heart to beat faster and require you to breathe faster than normal. When done for at least 20 minutes at a time at least three days a week, these activities build cardiorespiratory endurance and provide health benefits similar to those provided by vigorous aerobics. Examples of vigorous sports are tennis, basketball, badminton, volleyball, and soccer. Examples of vigorous recreation are hiking, backpacking, and biking.
The word vigorous is used in combination with the terms aerobics, sports, and recreation when describing activities at the second and third steps of the pyramid to make it clear that activities at these steps are more intense than moderate activities. Moderate physical activities at the first step of the pyramid are also considered to be aerobic because your body can supply enough oxygen to allow you to keep doing these activities for long periods of time. But they're not considered to be vigorous because they're not intense enough to build optimal levels of cardiorespiratory endurance.
Exercise is a word used to refer to physical activity that is done with the specific purpose of building physical fitness. Muscle fitness exercises are included in the fourth step of the Physical Activity Pyramid for Teens. Muscle fitness exercises are designed to build all three parts of muscle fitness including strength, muscular endurance, and power. One reason why this type of exercise is placed higher in the pyramid than other types is that these exercises need not be performed every day to get benefits. Experts recommend that teens do muscle fitness exercises (such as curl-ups and push-ups) at least two days a week. Muscle fitness exercises help you to build strong bones, prevent muscle injury, and gain many of the same health benefits as with activities from steps 1 through 3.
Flexibility exercises build flexibility and help you to perform well in daily life activities and sport. They may also help reduce risk of injury. They are placed at step 5 of the pyramid. While they can be performed daily, you can maintain flexibility by performing them on two or three days per week.
At the very top of the pyramid is a balance scale. This scale helps show the importance of energy balance. As noted earlier in this lesson, energy balance means that the calories in the food you eat each day are equal to the calories you expend in exercise each day. You must achieve energy balance in order to maintain a healthy body composition. Activities from all steps of the pyramid expend energy and help you balance energy.
At the bottom of the teen physical pyramid are two small pictures with big cross marks over them. One picture is of a video game controller and the other is a picture of a television set. The pictures are meant to caution against being inactive. Being inactive or sedentary isn't good for your health or fitness. It can also limit your productivity in school and in performing other important daily tasks. This does not mean that you should never play video games or watch television. The pictures are meant to indicate that it is good to limit screen time and to avoid being sedentary.
Inactivity, as used in the pyramid, doesn't include productive rest, such as sleep that allows recovery from the day's activities. For example, teens need at least 9 hours of sleep each day. As a teen you also need time for relaxation and productive light activities, such as reading and doing homework.
As noted earlier, to get all of the many benefits of physical activity, teens need to do 60 minutes of daily activity. Ideally you will do activities from each of the five steps each week. You will learn more about the formula for getting optimal benefits in later chapters of this book.
Fit Fact
Do You Sit Too Much?
Many teens spend more time watching TV and playing computer games than they do in school. Each day, you should spend at least as much time in moderate or vigorous activity as you do watching TV or playing inactive games.
Learn more about Fitness for Life: Middle School, Second Edition.
Why Should I Do Vigorous Aerobics?
Vigorous aerobic activities produce many of the same health and wellness benefits of moderate physical activities. One major benefit you get from vigorous aerobics that you can’t get from moderate physical activity is cardiorespiratory endurance.
Vigorous aerobic activities produce many of the same health and wellness benefits of moderate physical activities. One major benefit you get from vigorous aerobics that you can't get from moderate physical activity is cardiorespiratory endurance. In fact, vigorous aerobics is probably the best method of building good cardiorespiratory endurance. As you learned in chapter 1, cardiorespiratory endurance is the ability to perform exercise of your entire body for long periods of time without getting tired. It requires your heart, lungs, blood vessels, and blood to work efficiently and to supply the body with oxygen (figure 4.5). Some of the benefits of doing regular vigorous aerobics are explained in the following paragraphs.
Figure 4.5 Cardiorespiratory endurance requires fitness of many body systems.
Vigorous Aerobics and Cardiorespiratory Endurance for Sports
Teens interested in playing a sport should be very interested in vigorous aerobics because most sports require good cardiorespiratory endurance, and vigorous aerobics is a good way to get it. Sports such as cross-country running, track and field, skiing, swimming, soccer, and tennis are just a few that require cardiorespiratory endurance. You can't perform your best in sports unless you do activities that build good cardiorespiratory endurance.
Vigorous Aerobics and Cardiorespiratory Endurance for Health
Teens who do moderate physical activity get health benefits such as a reduced risk of developing certain diseases. Teens who also do vigorous aerobics get similar benefits and more! Vigorous aerobics can help you get out of the low fitness zone and into the healthy fitness zone for cardiorespiratory endurance.
Vigorous Aerobics and Cardiorespiratory Endurance for Wellness
Vigorous aerobics and the cardiorespiratory endurance that it produces help you to feel and look your best by burning calories and keeping off body fat. You'll feel your best because you'll be less tired. Best of all, you'll have fun because you'll be participating in activities that you enjoy.
Cardiorespiratory Endurance and Safety
In some special cases, people need to run to get help, shovel sand into sandbags, or even shovel snow for long periods of time. Good cardiorespiratory endurance would help a person to perform activities such as these.
Cardiorespiratory Endurance for Work
Certain jobs require cardiorespiratory endurance. For example, to get a job as a member of a fire or police department, you need good cardiorespiratory endurance. Park rangers, lifeguards, construction workers, ranchers, farmers, fitness instructors, and members of the military all must have good cardiorespiratory endurance. Any job that requires you to work for long periods of time and that causes your heart to beat fast requires good cardiorespiratory endurance.
Fit Fact
Blood Flow During Exercise
When you begin exercising, the blood vessels to your exercising muscles expand, and the blood vessels to your stomach and intestines contract. This increases the blood flow to your working muscles.
Firefighters and lifeguards must have good cardiorespiratory endurance.
© iStockphoto/Tim McCaig
Learn more about Fitness for Life: Middle School, Second Edition.
How Can I Assess My Body Composition?
Body fat is one important component of body composition. Ideally, people shouldn’t have too much or too little body fat. The goal is to be in the healthy fitness zone for your level of body fat.
Body fat is one important component of body composition. Ideally, people shouldn't have too much or too little body fat. The goal is to be in the healthy fitness zone for your level of body fat. The best methods of assessing a person's body fat level involve the use of X-ray machines and special water measurement tanks. These tests are expensive and can't be used quickly, so they aren't practical for general school classes. There are several methods of assessment that are commonly used in schools.
Some schools use a bioelectrical impedance analysis (BIA) machine to assess body fat levels (figure 8.3). Bioelectrical impedance machines have been shown to be quite accurate when used properly. The machine detects differences in water, lean body tissue, and fat, allowing it to estimate the amount of body fat that a person has. Schools that do not have BIA machines can use two other inexpensive methods: body mass index and skinfold measurements.
Figure 8.3 BIA machines can be used to assess body fat levels.
The most common body composition measurement used in schools is called the body mass index (BMI). As described in a special feature later in this lesson, you use your height and weight in a formula to calculate your BMI. The BMI doesn't directly assess body fat levels, but it does help you determine if you are in the healthy fitness zone. The BMI is a test commonly used in FitnessGram.
The BMI uses a formula to determine if you're overweight. The term overweight simply refers to having a BMI (combination of height and weight) that is higher than recommended for good health. Being overweight isn't the same as being high in body fat. It's possible to be high in weight without being too fat, because muscle weighs more than fat. People with a lot of muscle weigh more than people of the same size with less muscle. Even though there are limitations to the BMI, scientists indicate that people with a high BMI have more risk for heart disease, diabetes, and other chronic diseases than people with a BMI in the healthy fitness zone. A person who has an exceptionally high BMI without an exceptionally high amount of muscle or who has an exceptionally high amount of body fat is considered to be obese.
Fit Fact
Overweight in America
Two-thirds of adults and one-third of children and teens are considered to be either overweight or obese, resulting in increased chronic disease risk for many Americans.
Another method of assessing body composition is called skinfold measurements (figure 8.4). As shown in the photo, fat located under the skin is measured using a pair of skinfold calipers. The calipers are used to measure the thickness of fat folds beneath the skin. This test estimates the amount of fat in the body. Skinfold measurements are not as accurate as X-rays and underwater weighing, but they are often used because they give a good estimate of body fat levels and require only a relatively inexpensive pair of calipers and a trained person such as a teacher.
Figure 8.4 Calipers are used to make skinfold measurements.
The results of either the BMI or skinfold measurement tests will help you determine if you are in the healthy fitness zone. Your test results will show if you're in a zone that helps you function effectively and avoid problems associated with having too much or too little body fat or body weight.
Information about your body weight and body composition is personal. In fact, you have the right to treat all fitness testing results as private information. If people ask about your body weight, body composition, or other private information that you're not comfortable sharing, you can make a statement such as, "I don't feel comfortable sharing my personal information. Could you please respect my desire to keep personal information private?"
You should also help others keep their personal information private. For example, don't ask other people about their body weight or body composition. Also, if you work with a partner, keep that person's information private. In chapter 4, you learned some guidelines that you can use to build self-esteem. You may want to review those guidelines at this time.
You can take other steps to keep information confidential. One of the best ways is to share it only with people you trust, and only after asking them to keep the information private. Over time, you can build caring relationships with others, and this will reduce your need to worry about privacy. Sometimes, feeling comfortable in sharing information relieves the pressure of trying to keep things private.
Body Mass Index
Follow these steps and record your results.
- Measure your height in inches or meters without shoes.
- Measure your weight in pounds or kilograms without shoes. If you're wearing street clothes (as opposed to lightweight gym clothing), subtract 2 pounds or 1 kilogram from your weight.
- Use the body mass index chart to determine your BMI. You can also calculate your BMI using either of the following formulas:
BMI = weight in kilograms/(height in meters)2
BMI = weight in pounds/(height in inches)2 × 703
- Use table 8.1 to determine your rating for BMI.
Text adapted from C.B. Corbin and G.C. Le Masurier, 2014, Fitness for life, 6th ed. (Champaign, IL: Human Kinetics), 80.
| |
Height/Weight to BMI chart. Locate the row containing your height (left) and column containing your weight (bottom). The value in the box where rows and columns meet is your BMI.
Save
Save
Learn more about Fitness for Life: Middle School, Second Edition.
What Is Physical Activity?
Physical activity occurs when your muscles contract to make your body move. The national physical activity guidelines for teens recommend at least 60 minutes, and up to several hours, of physical activity each day of the week.
Physical activity occurs when your muscles contract to make your body move. The national physical activity guidelines for teens recommend at least 60 minutes, and up to several hours, of physical activity each day of the week. The guidelines recommend that teens perform a variety of activities. There are five basic types of physical activity from which you can choose to meet the national activity recommendation for youth. In this book the Physical Activity Pyramid for Teens is used to illustrate each of the different types of activities (see figure 1.2).
Figure 1.2 The Physical Activity Pyramid for Teens includes many types of activities.
© Charles Corbin
How Do I Know if I Am Active Enough?
In general you are active enough for good health if you meet the national teen guideline of 60 minutes or more of physical activity per day. However, the guidelines indicate that you should do a variety of activities and include some vigorous physical activity and some activity for building muscle fitness and for building strong bones. If you perform a variety of activities from the Physical Activity Pyramid you will meet the national guidelines. In the paragraphs that follow you will learn more about the pyramid.
There is a popular saying that "a picture is worth a thousand words." The saying means remembering a picture may be better than trying to remember a lot of words. So in this book the Physical Activity Pyramid picture is used to help you remember the five types of physical activity. Activities such as moderate physical activity are placed at the wide base of the pyramid because they typically are performed more regularly by people than activities higher in the pyramid. Activities at the bottom typically need to be performed more often than those higher in the pyramid to get benefits. The pyramid also has a triangle at the top that helps you remember the need for energy balance. Energy balance means expending as many calories in physical activity as the calories you consume in food. To get fitness, health, wellness, and energy balance you should choose activities from each of the five steps of the pyramid. You can combine activities from all five steps to meet the daily activity recommendation.
The first step in the pyramid includes moderate physical activities. The intensity of moderate activities is not too easy and not too hard. Any activity that is about as intense as walking briskly is considered moderate. One reason why moderate activities are placed at the bottom of the pyramid is that more people do moderate activity than any other type of activity. Moderate activities are also placed at the wide base of the pyramid because you get the best results when you do them on all or most days of the week. Activities at higher steps in the pyramid can be done less frequently and still provide important benefits.
Many moderate activities are sometimes referred to as lifestyle activities because you do them as part of your daily life. Examples include walking to school, working around the house, and working in the yard. Experts recommend that adults do moderate physical activity for 30 minutes or more each day. This is because activities from step 1 of the Physical Activity Pyramid help people reduce their risk of disease and help them maintain a healthy body weight. Some moderate activities are called lifetime activities because you can do them when you're young as well as when you grow older. Some activities from other steps of the pyramid are also considered to be lifetime activities. Examples include sports such as bowling and golf and recreational activities such as fishing because they're moderate in intensity. As you'll learn later in this book, it's recommended that teens do regular moderate activity to develop activity habits that can be used throughout life.
Vigorous aerobics is included in the second step of the Physical Activity Pyramid. Vigorous aerobics is a type of vigorous physical activity that is especially good for building cardiorespiratory endurance. The word aerobic means "with oxygen." In aerobic activities, your body supplies oxygen to keep you going. When your heart beats faster than normal during vigorous aerobics, your heart supplies your body with the oxygen it needs to keep going. Vigorous aerobics is the most popular type of vigorous physical activity for people of all ages. Examples of vigorous aerobics are running, swimming, in-line skating, aerobic dance, and biking at a vigorous intensity.
Vigorous sports and vigorous recreation at the third step of the pyramid also require your heart to beat faster and require you to breathe faster than normal. When done for at least 20 minutes at a time at least three days a week, these activities build cardiorespiratory endurance and provide health benefits similar to those provided by vigorous aerobics. Examples of vigorous sports are tennis, basketball, badminton, volleyball, and soccer. Examples of vigorous recreation are hiking, backpacking, and biking.
The word vigorous is used in combination with the terms aerobics, sports, and recreation when describing activities at the second and third steps of the pyramid to make it clear that activities at these steps are more intense than moderate activities. Moderate physical activities at the first step of the pyramid are also considered to be aerobic because your body can supply enough oxygen to allow you to keep doing these activities for long periods of time. But they're not considered to be vigorous because they're not intense enough to build optimal levels of cardiorespiratory endurance.
Exercise is a word used to refer to physical activity that is done with the specific purpose of building physical fitness. Muscle fitness exercises are included in the fourth step of the Physical Activity Pyramid for Teens. Muscle fitness exercises are designed to build all three parts of muscle fitness including strength, muscular endurance, and power. One reason why this type of exercise is placed higher in the pyramid than other types is that these exercises need not be performed every day to get benefits. Experts recommend that teens do muscle fitness exercises (such as curl-ups and push-ups) at least two days a week. Muscle fitness exercises help you to build strong bones, prevent muscle injury, and gain many of the same health benefits as with activities from steps 1 through 3.
Flexibility exercises build flexibility and help you to perform well in daily life activities and sport. They may also help reduce risk of injury. They are placed at step 5 of the pyramid. While they can be performed daily, you can maintain flexibility by performing them on two or three days per week.
At the very top of the pyramid is a balance scale. This scale helps show the importance of energy balance. As noted earlier in this lesson, energy balance means that the calories in the food you eat each day are equal to the calories you expend in exercise each day. You must achieve energy balance in order to maintain a healthy body composition. Activities from all steps of the pyramid expend energy and help you balance energy.
At the bottom of the teen physical pyramid are two small pictures with big cross marks over them. One picture is of a video game controller and the other is a picture of a television set. The pictures are meant to caution against being inactive. Being inactive or sedentary isn't good for your health or fitness. It can also limit your productivity in school and in performing other important daily tasks. This does not mean that you should never play video games or watch television. The pictures are meant to indicate that it is good to limit screen time and to avoid being sedentary.
Inactivity, as used in the pyramid, doesn't include productive rest, such as sleep that allows recovery from the day's activities. For example, teens need at least 9 hours of sleep each day. As a teen you also need time for relaxation and productive light activities, such as reading and doing homework.
As noted earlier, to get all of the many benefits of physical activity, teens need to do 60 minutes of daily activity. Ideally you will do activities from each of the five steps each week. You will learn more about the formula for getting optimal benefits in later chapters of this book.
Fit Fact
Do You Sit Too Much?
Many teens spend more time watching TV and playing computer games than they do in school. Each day, you should spend at least as much time in moderate or vigorous activity as you do watching TV or playing inactive games.
Learn more about Fitness for Life: Middle School, Second Edition.
Why Should I Do Vigorous Aerobics?
Vigorous aerobic activities produce many of the same health and wellness benefits of moderate physical activities. One major benefit you get from vigorous aerobics that you can’t get from moderate physical activity is cardiorespiratory endurance.
Vigorous aerobic activities produce many of the same health and wellness benefits of moderate physical activities. One major benefit you get from vigorous aerobics that you can't get from moderate physical activity is cardiorespiratory endurance. In fact, vigorous aerobics is probably the best method of building good cardiorespiratory endurance. As you learned in chapter 1, cardiorespiratory endurance is the ability to perform exercise of your entire body for long periods of time without getting tired. It requires your heart, lungs, blood vessels, and blood to work efficiently and to supply the body with oxygen (figure 4.5). Some of the benefits of doing regular vigorous aerobics are explained in the following paragraphs.
Figure 4.5 Cardiorespiratory endurance requires fitness of many body systems.
Vigorous Aerobics and Cardiorespiratory Endurance for Sports
Teens interested in playing a sport should be very interested in vigorous aerobics because most sports require good cardiorespiratory endurance, and vigorous aerobics is a good way to get it. Sports such as cross-country running, track and field, skiing, swimming, soccer, and tennis are just a few that require cardiorespiratory endurance. You can't perform your best in sports unless you do activities that build good cardiorespiratory endurance.
Vigorous Aerobics and Cardiorespiratory Endurance for Health
Teens who do moderate physical activity get health benefits such as a reduced risk of developing certain diseases. Teens who also do vigorous aerobics get similar benefits and more! Vigorous aerobics can help you get out of the low fitness zone and into the healthy fitness zone for cardiorespiratory endurance.
Vigorous Aerobics and Cardiorespiratory Endurance for Wellness
Vigorous aerobics and the cardiorespiratory endurance that it produces help you to feel and look your best by burning calories and keeping off body fat. You'll feel your best because you'll be less tired. Best of all, you'll have fun because you'll be participating in activities that you enjoy.
Cardiorespiratory Endurance and Safety
In some special cases, people need to run to get help, shovel sand into sandbags, or even shovel snow for long periods of time. Good cardiorespiratory endurance would help a person to perform activities such as these.
Cardiorespiratory Endurance for Work
Certain jobs require cardiorespiratory endurance. For example, to get a job as a member of a fire or police department, you need good cardiorespiratory endurance. Park rangers, lifeguards, construction workers, ranchers, farmers, fitness instructors, and members of the military all must have good cardiorespiratory endurance. Any job that requires you to work for long periods of time and that causes your heart to beat fast requires good cardiorespiratory endurance.
Fit Fact
Blood Flow During Exercise
When you begin exercising, the blood vessels to your exercising muscles expand, and the blood vessels to your stomach and intestines contract. This increases the blood flow to your working muscles.
Firefighters and lifeguards must have good cardiorespiratory endurance.
© iStockphoto/Tim McCaig
Learn more about Fitness for Life: Middle School, Second Edition.
How Can I Assess My Body Composition?
Body fat is one important component of body composition. Ideally, people shouldn’t have too much or too little body fat. The goal is to be in the healthy fitness zone for your level of body fat.
Body fat is one important component of body composition. Ideally, people shouldn't have too much or too little body fat. The goal is to be in the healthy fitness zone for your level of body fat. The best methods of assessing a person's body fat level involve the use of X-ray machines and special water measurement tanks. These tests are expensive and can't be used quickly, so they aren't practical for general school classes. There are several methods of assessment that are commonly used in schools.
Some schools use a bioelectrical impedance analysis (BIA) machine to assess body fat levels (figure 8.3). Bioelectrical impedance machines have been shown to be quite accurate when used properly. The machine detects differences in water, lean body tissue, and fat, allowing it to estimate the amount of body fat that a person has. Schools that do not have BIA machines can use two other inexpensive methods: body mass index and skinfold measurements.
Figure 8.3 BIA machines can be used to assess body fat levels.
The most common body composition measurement used in schools is called the body mass index (BMI). As described in a special feature later in this lesson, you use your height and weight in a formula to calculate your BMI. The BMI doesn't directly assess body fat levels, but it does help you determine if you are in the healthy fitness zone. The BMI is a test commonly used in FitnessGram.
The BMI uses a formula to determine if you're overweight. The term overweight simply refers to having a BMI (combination of height and weight) that is higher than recommended for good health. Being overweight isn't the same as being high in body fat. It's possible to be high in weight without being too fat, because muscle weighs more than fat. People with a lot of muscle weigh more than people of the same size with less muscle. Even though there are limitations to the BMI, scientists indicate that people with a high BMI have more risk for heart disease, diabetes, and other chronic diseases than people with a BMI in the healthy fitness zone. A person who has an exceptionally high BMI without an exceptionally high amount of muscle or who has an exceptionally high amount of body fat is considered to be obese.
Fit Fact
Overweight in America
Two-thirds of adults and one-third of children and teens are considered to be either overweight or obese, resulting in increased chronic disease risk for many Americans.
Another method of assessing body composition is called skinfold measurements (figure 8.4). As shown in the photo, fat located under the skin is measured using a pair of skinfold calipers. The calipers are used to measure the thickness of fat folds beneath the skin. This test estimates the amount of fat in the body. Skinfold measurements are not as accurate as X-rays and underwater weighing, but they are often used because they give a good estimate of body fat levels and require only a relatively inexpensive pair of calipers and a trained person such as a teacher.
Figure 8.4 Calipers are used to make skinfold measurements.
The results of either the BMI or skinfold measurement tests will help you determine if you are in the healthy fitness zone. Your test results will show if you're in a zone that helps you function effectively and avoid problems associated with having too much or too little body fat or body weight.
Information about your body weight and body composition is personal. In fact, you have the right to treat all fitness testing results as private information. If people ask about your body weight, body composition, or other private information that you're not comfortable sharing, you can make a statement such as, "I don't feel comfortable sharing my personal information. Could you please respect my desire to keep personal information private?"
You should also help others keep their personal information private. For example, don't ask other people about their body weight or body composition. Also, if you work with a partner, keep that person's information private. In chapter 4, you learned some guidelines that you can use to build self-esteem. You may want to review those guidelines at this time.
You can take other steps to keep information confidential. One of the best ways is to share it only with people you trust, and only after asking them to keep the information private. Over time, you can build caring relationships with others, and this will reduce your need to worry about privacy. Sometimes, feeling comfortable in sharing information relieves the pressure of trying to keep things private.
Body Mass Index
Follow these steps and record your results.
- Measure your height in inches or meters without shoes.
- Measure your weight in pounds or kilograms without shoes. If you're wearing street clothes (as opposed to lightweight gym clothing), subtract 2 pounds or 1 kilogram from your weight.
- Use the body mass index chart to determine your BMI. You can also calculate your BMI using either of the following formulas:
BMI = weight in kilograms/(height in meters)2
BMI = weight in pounds/(height in inches)2 × 703
- Use table 8.1 to determine your rating for BMI.
Text adapted from C.B. Corbin and G.C. Le Masurier, 2014, Fitness for life, 6th ed. (Champaign, IL: Human Kinetics), 80.
| |
Height/Weight to BMI chart. Locate the row containing your height (left) and column containing your weight (bottom). The value in the box where rows and columns meet is your BMI.
Save
Save
Learn more about Fitness for Life: Middle School, Second Edition.
What Is Physical Activity?
Physical activity occurs when your muscles contract to make your body move. The national physical activity guidelines for teens recommend at least 60 minutes, and up to several hours, of physical activity each day of the week.
Physical activity occurs when your muscles contract to make your body move. The national physical activity guidelines for teens recommend at least 60 minutes, and up to several hours, of physical activity each day of the week. The guidelines recommend that teens perform a variety of activities. There are five basic types of physical activity from which you can choose to meet the national activity recommendation for youth. In this book the Physical Activity Pyramid for Teens is used to illustrate each of the different types of activities (see figure 1.2).
Figure 1.2 The Physical Activity Pyramid for Teens includes many types of activities.
© Charles Corbin
How Do I Know if I Am Active Enough?
In general you are active enough for good health if you meet the national teen guideline of 60 minutes or more of physical activity per day. However, the guidelines indicate that you should do a variety of activities and include some vigorous physical activity and some activity for building muscle fitness and for building strong bones. If you perform a variety of activities from the Physical Activity Pyramid you will meet the national guidelines. In the paragraphs that follow you will learn more about the pyramid.
There is a popular saying that "a picture is worth a thousand words." The saying means remembering a picture may be better than trying to remember a lot of words. So in this book the Physical Activity Pyramid picture is used to help you remember the five types of physical activity. Activities such as moderate physical activity are placed at the wide base of the pyramid because they typically are performed more regularly by people than activities higher in the pyramid. Activities at the bottom typically need to be performed more often than those higher in the pyramid to get benefits. The pyramid also has a triangle at the top that helps you remember the need for energy balance. Energy balance means expending as many calories in physical activity as the calories you consume in food. To get fitness, health, wellness, and energy balance you should choose activities from each of the five steps of the pyramid. You can combine activities from all five steps to meet the daily activity recommendation.
The first step in the pyramid includes moderate physical activities. The intensity of moderate activities is not too easy and not too hard. Any activity that is about as intense as walking briskly is considered moderate. One reason why moderate activities are placed at the bottom of the pyramid is that more people do moderate activity than any other type of activity. Moderate activities are also placed at the wide base of the pyramid because you get the best results when you do them on all or most days of the week. Activities at higher steps in the pyramid can be done less frequently and still provide important benefits.
Many moderate activities are sometimes referred to as lifestyle activities because you do them as part of your daily life. Examples include walking to school, working around the house, and working in the yard. Experts recommend that adults do moderate physical activity for 30 minutes or more each day. This is because activities from step 1 of the Physical Activity Pyramid help people reduce their risk of disease and help them maintain a healthy body weight. Some moderate activities are called lifetime activities because you can do them when you're young as well as when you grow older. Some activities from other steps of the pyramid are also considered to be lifetime activities. Examples include sports such as bowling and golf and recreational activities such as fishing because they're moderate in intensity. As you'll learn later in this book, it's recommended that teens do regular moderate activity to develop activity habits that can be used throughout life.
Vigorous aerobics is included in the second step of the Physical Activity Pyramid. Vigorous aerobics is a type of vigorous physical activity that is especially good for building cardiorespiratory endurance. The word aerobic means "with oxygen." In aerobic activities, your body supplies oxygen to keep you going. When your heart beats faster than normal during vigorous aerobics, your heart supplies your body with the oxygen it needs to keep going. Vigorous aerobics is the most popular type of vigorous physical activity for people of all ages. Examples of vigorous aerobics are running, swimming, in-line skating, aerobic dance, and biking at a vigorous intensity.
Vigorous sports and vigorous recreation at the third step of the pyramid also require your heart to beat faster and require you to breathe faster than normal. When done for at least 20 minutes at a time at least three days a week, these activities build cardiorespiratory endurance and provide health benefits similar to those provided by vigorous aerobics. Examples of vigorous sports are tennis, basketball, badminton, volleyball, and soccer. Examples of vigorous recreation are hiking, backpacking, and biking.
The word vigorous is used in combination with the terms aerobics, sports, and recreation when describing activities at the second and third steps of the pyramid to make it clear that activities at these steps are more intense than moderate activities. Moderate physical activities at the first step of the pyramid are also considered to be aerobic because your body can supply enough oxygen to allow you to keep doing these activities for long periods of time. But they're not considered to be vigorous because they're not intense enough to build optimal levels of cardiorespiratory endurance.
Exercise is a word used to refer to physical activity that is done with the specific purpose of building physical fitness. Muscle fitness exercises are included in the fourth step of the Physical Activity Pyramid for Teens. Muscle fitness exercises are designed to build all three parts of muscle fitness including strength, muscular endurance, and power. One reason why this type of exercise is placed higher in the pyramid than other types is that these exercises need not be performed every day to get benefits. Experts recommend that teens do muscle fitness exercises (such as curl-ups and push-ups) at least two days a week. Muscle fitness exercises help you to build strong bones, prevent muscle injury, and gain many of the same health benefits as with activities from steps 1 through 3.
Flexibility exercises build flexibility and help you to perform well in daily life activities and sport. They may also help reduce risk of injury. They are placed at step 5 of the pyramid. While they can be performed daily, you can maintain flexibility by performing them on two or three days per week.
At the very top of the pyramid is a balance scale. This scale helps show the importance of energy balance. As noted earlier in this lesson, energy balance means that the calories in the food you eat each day are equal to the calories you expend in exercise each day. You must achieve energy balance in order to maintain a healthy body composition. Activities from all steps of the pyramid expend energy and help you balance energy.
At the bottom of the teen physical pyramid are two small pictures with big cross marks over them. One picture is of a video game controller and the other is a picture of a television set. The pictures are meant to caution against being inactive. Being inactive or sedentary isn't good for your health or fitness. It can also limit your productivity in school and in performing other important daily tasks. This does not mean that you should never play video games or watch television. The pictures are meant to indicate that it is good to limit screen time and to avoid being sedentary.
Inactivity, as used in the pyramid, doesn't include productive rest, such as sleep that allows recovery from the day's activities. For example, teens need at least 9 hours of sleep each day. As a teen you also need time for relaxation and productive light activities, such as reading and doing homework.
As noted earlier, to get all of the many benefits of physical activity, teens need to do 60 minutes of daily activity. Ideally you will do activities from each of the five steps each week. You will learn more about the formula for getting optimal benefits in later chapters of this book.
Fit Fact
Do You Sit Too Much?
Many teens spend more time watching TV and playing computer games than they do in school. Each day, you should spend at least as much time in moderate or vigorous activity as you do watching TV or playing inactive games.
Learn more about Fitness for Life: Middle School, Second Edition.
Why Should I Do Vigorous Aerobics?
Vigorous aerobic activities produce many of the same health and wellness benefits of moderate physical activities. One major benefit you get from vigorous aerobics that you can’t get from moderate physical activity is cardiorespiratory endurance.
Vigorous aerobic activities produce many of the same health and wellness benefits of moderate physical activities. One major benefit you get from vigorous aerobics that you can't get from moderate physical activity is cardiorespiratory endurance. In fact, vigorous aerobics is probably the best method of building good cardiorespiratory endurance. As you learned in chapter 1, cardiorespiratory endurance is the ability to perform exercise of your entire body for long periods of time without getting tired. It requires your heart, lungs, blood vessels, and blood to work efficiently and to supply the body with oxygen (figure 4.5). Some of the benefits of doing regular vigorous aerobics are explained in the following paragraphs.
Figure 4.5 Cardiorespiratory endurance requires fitness of many body systems.
Vigorous Aerobics and Cardiorespiratory Endurance for Sports
Teens interested in playing a sport should be very interested in vigorous aerobics because most sports require good cardiorespiratory endurance, and vigorous aerobics is a good way to get it. Sports such as cross-country running, track and field, skiing, swimming, soccer, and tennis are just a few that require cardiorespiratory endurance. You can't perform your best in sports unless you do activities that build good cardiorespiratory endurance.
Vigorous Aerobics and Cardiorespiratory Endurance for Health
Teens who do moderate physical activity get health benefits such as a reduced risk of developing certain diseases. Teens who also do vigorous aerobics get similar benefits and more! Vigorous aerobics can help you get out of the low fitness zone and into the healthy fitness zone for cardiorespiratory endurance.
Vigorous Aerobics and Cardiorespiratory Endurance for Wellness
Vigorous aerobics and the cardiorespiratory endurance that it produces help you to feel and look your best by burning calories and keeping off body fat. You'll feel your best because you'll be less tired. Best of all, you'll have fun because you'll be participating in activities that you enjoy.
Cardiorespiratory Endurance and Safety
In some special cases, people need to run to get help, shovel sand into sandbags, or even shovel snow for long periods of time. Good cardiorespiratory endurance would help a person to perform activities such as these.
Cardiorespiratory Endurance for Work
Certain jobs require cardiorespiratory endurance. For example, to get a job as a member of a fire or police department, you need good cardiorespiratory endurance. Park rangers, lifeguards, construction workers, ranchers, farmers, fitness instructors, and members of the military all must have good cardiorespiratory endurance. Any job that requires you to work for long periods of time and that causes your heart to beat fast requires good cardiorespiratory endurance.
Fit Fact
Blood Flow During Exercise
When you begin exercising, the blood vessels to your exercising muscles expand, and the blood vessels to your stomach and intestines contract. This increases the blood flow to your working muscles.
Firefighters and lifeguards must have good cardiorespiratory endurance.
© iStockphoto/Tim McCaig
Learn more about Fitness for Life: Middle School, Second Edition.
How Can I Assess My Body Composition?
Body fat is one important component of body composition. Ideally, people shouldn’t have too much or too little body fat. The goal is to be in the healthy fitness zone for your level of body fat.
Body fat is one important component of body composition. Ideally, people shouldn't have too much or too little body fat. The goal is to be in the healthy fitness zone for your level of body fat. The best methods of assessing a person's body fat level involve the use of X-ray machines and special water measurement tanks. These tests are expensive and can't be used quickly, so they aren't practical for general school classes. There are several methods of assessment that are commonly used in schools.
Some schools use a bioelectrical impedance analysis (BIA) machine to assess body fat levels (figure 8.3). Bioelectrical impedance machines have been shown to be quite accurate when used properly. The machine detects differences in water, lean body tissue, and fat, allowing it to estimate the amount of body fat that a person has. Schools that do not have BIA machines can use two other inexpensive methods: body mass index and skinfold measurements.
Figure 8.3 BIA machines can be used to assess body fat levels.
The most common body composition measurement used in schools is called the body mass index (BMI). As described in a special feature later in this lesson, you use your height and weight in a formula to calculate your BMI. The BMI doesn't directly assess body fat levels, but it does help you determine if you are in the healthy fitness zone. The BMI is a test commonly used in FitnessGram.
The BMI uses a formula to determine if you're overweight. The term overweight simply refers to having a BMI (combination of height and weight) that is higher than recommended for good health. Being overweight isn't the same as being high in body fat. It's possible to be high in weight without being too fat, because muscle weighs more than fat. People with a lot of muscle weigh more than people of the same size with less muscle. Even though there are limitations to the BMI, scientists indicate that people with a high BMI have more risk for heart disease, diabetes, and other chronic diseases than people with a BMI in the healthy fitness zone. A person who has an exceptionally high BMI without an exceptionally high amount of muscle or who has an exceptionally high amount of body fat is considered to be obese.
Fit Fact
Overweight in America
Two-thirds of adults and one-third of children and teens are considered to be either overweight or obese, resulting in increased chronic disease risk for many Americans.
Another method of assessing body composition is called skinfold measurements (figure 8.4). As shown in the photo, fat located under the skin is measured using a pair of skinfold calipers. The calipers are used to measure the thickness of fat folds beneath the skin. This test estimates the amount of fat in the body. Skinfold measurements are not as accurate as X-rays and underwater weighing, but they are often used because they give a good estimate of body fat levels and require only a relatively inexpensive pair of calipers and a trained person such as a teacher.
Figure 8.4 Calipers are used to make skinfold measurements.
The results of either the BMI or skinfold measurement tests will help you determine if you are in the healthy fitness zone. Your test results will show if you're in a zone that helps you function effectively and avoid problems associated with having too much or too little body fat or body weight.
Information about your body weight and body composition is personal. In fact, you have the right to treat all fitness testing results as private information. If people ask about your body weight, body composition, or other private information that you're not comfortable sharing, you can make a statement such as, "I don't feel comfortable sharing my personal information. Could you please respect my desire to keep personal information private?"
You should also help others keep their personal information private. For example, don't ask other people about their body weight or body composition. Also, if you work with a partner, keep that person's information private. In chapter 4, you learned some guidelines that you can use to build self-esteem. You may want to review those guidelines at this time.
You can take other steps to keep information confidential. One of the best ways is to share it only with people you trust, and only after asking them to keep the information private. Over time, you can build caring relationships with others, and this will reduce your need to worry about privacy. Sometimes, feeling comfortable in sharing information relieves the pressure of trying to keep things private.
Body Mass Index
Follow these steps and record your results.
- Measure your height in inches or meters without shoes.
- Measure your weight in pounds or kilograms without shoes. If you're wearing street clothes (as opposed to lightweight gym clothing), subtract 2 pounds or 1 kilogram from your weight.
- Use the body mass index chart to determine your BMI. You can also calculate your BMI using either of the following formulas:
BMI = weight in kilograms/(height in meters)2
BMI = weight in pounds/(height in inches)2 × 703
- Use table 8.1 to determine your rating for BMI.
Text adapted from C.B. Corbin and G.C. Le Masurier, 2014, Fitness for life, 6th ed. (Champaign, IL: Human Kinetics), 80.
| |
Height/Weight to BMI chart. Locate the row containing your height (left) and column containing your weight (bottom). The value in the box where rows and columns meet is your BMI.
Save
Save
Learn more about Fitness for Life: Middle School, Second Edition.
What Is Physical Activity?
Physical activity occurs when your muscles contract to make your body move. The national physical activity guidelines for teens recommend at least 60 minutes, and up to several hours, of physical activity each day of the week.
Physical activity occurs when your muscles contract to make your body move. The national physical activity guidelines for teens recommend at least 60 minutes, and up to several hours, of physical activity each day of the week. The guidelines recommend that teens perform a variety of activities. There are five basic types of physical activity from which you can choose to meet the national activity recommendation for youth. In this book the Physical Activity Pyramid for Teens is used to illustrate each of the different types of activities (see figure 1.2).
Figure 1.2 The Physical Activity Pyramid for Teens includes many types of activities.
© Charles Corbin
How Do I Know if I Am Active Enough?
In general you are active enough for good health if you meet the national teen guideline of 60 minutes or more of physical activity per day. However, the guidelines indicate that you should do a variety of activities and include some vigorous physical activity and some activity for building muscle fitness and for building strong bones. If you perform a variety of activities from the Physical Activity Pyramid you will meet the national guidelines. In the paragraphs that follow you will learn more about the pyramid.
There is a popular saying that "a picture is worth a thousand words." The saying means remembering a picture may be better than trying to remember a lot of words. So in this book the Physical Activity Pyramid picture is used to help you remember the five types of physical activity. Activities such as moderate physical activity are placed at the wide base of the pyramid because they typically are performed more regularly by people than activities higher in the pyramid. Activities at the bottom typically need to be performed more often than those higher in the pyramid to get benefits. The pyramid also has a triangle at the top that helps you remember the need for energy balance. Energy balance means expending as many calories in physical activity as the calories you consume in food. To get fitness, health, wellness, and energy balance you should choose activities from each of the five steps of the pyramid. You can combine activities from all five steps to meet the daily activity recommendation.
The first step in the pyramid includes moderate physical activities. The intensity of moderate activities is not too easy and not too hard. Any activity that is about as intense as walking briskly is considered moderate. One reason why moderate activities are placed at the bottom of the pyramid is that more people do moderate activity than any other type of activity. Moderate activities are also placed at the wide base of the pyramid because you get the best results when you do them on all or most days of the week. Activities at higher steps in the pyramid can be done less frequently and still provide important benefits.
Many moderate activities are sometimes referred to as lifestyle activities because you do them as part of your daily life. Examples include walking to school, working around the house, and working in the yard. Experts recommend that adults do moderate physical activity for 30 minutes or more each day. This is because activities from step 1 of the Physical Activity Pyramid help people reduce their risk of disease and help them maintain a healthy body weight. Some moderate activities are called lifetime activities because you can do them when you're young as well as when you grow older. Some activities from other steps of the pyramid are also considered to be lifetime activities. Examples include sports such as bowling and golf and recreational activities such as fishing because they're moderate in intensity. As you'll learn later in this book, it's recommended that teens do regular moderate activity to develop activity habits that can be used throughout life.
Vigorous aerobics is included in the second step of the Physical Activity Pyramid. Vigorous aerobics is a type of vigorous physical activity that is especially good for building cardiorespiratory endurance. The word aerobic means "with oxygen." In aerobic activities, your body supplies oxygen to keep you going. When your heart beats faster than normal during vigorous aerobics, your heart supplies your body with the oxygen it needs to keep going. Vigorous aerobics is the most popular type of vigorous physical activity for people of all ages. Examples of vigorous aerobics are running, swimming, in-line skating, aerobic dance, and biking at a vigorous intensity.
Vigorous sports and vigorous recreation at the third step of the pyramid also require your heart to beat faster and require you to breathe faster than normal. When done for at least 20 minutes at a time at least three days a week, these activities build cardiorespiratory endurance and provide health benefits similar to those provided by vigorous aerobics. Examples of vigorous sports are tennis, basketball, badminton, volleyball, and soccer. Examples of vigorous recreation are hiking, backpacking, and biking.
The word vigorous is used in combination with the terms aerobics, sports, and recreation when describing activities at the second and third steps of the pyramid to make it clear that activities at these steps are more intense than moderate activities. Moderate physical activities at the first step of the pyramid are also considered to be aerobic because your body can supply enough oxygen to allow you to keep doing these activities for long periods of time. But they're not considered to be vigorous because they're not intense enough to build optimal levels of cardiorespiratory endurance.
Exercise is a word used to refer to physical activity that is done with the specific purpose of building physical fitness. Muscle fitness exercises are included in the fourth step of the Physical Activity Pyramid for Teens. Muscle fitness exercises are designed to build all three parts of muscle fitness including strength, muscular endurance, and power. One reason why this type of exercise is placed higher in the pyramid than other types is that these exercises need not be performed every day to get benefits. Experts recommend that teens do muscle fitness exercises (such as curl-ups and push-ups) at least two days a week. Muscle fitness exercises help you to build strong bones, prevent muscle injury, and gain many of the same health benefits as with activities from steps 1 through 3.
Flexibility exercises build flexibility and help you to perform well in daily life activities and sport. They may also help reduce risk of injury. They are placed at step 5 of the pyramid. While they can be performed daily, you can maintain flexibility by performing them on two or three days per week.
At the very top of the pyramid is a balance scale. This scale helps show the importance of energy balance. As noted earlier in this lesson, energy balance means that the calories in the food you eat each day are equal to the calories you expend in exercise each day. You must achieve energy balance in order to maintain a healthy body composition. Activities from all steps of the pyramid expend energy and help you balance energy.
At the bottom of the teen physical pyramid are two small pictures with big cross marks over them. One picture is of a video game controller and the other is a picture of a television set. The pictures are meant to caution against being inactive. Being inactive or sedentary isn't good for your health or fitness. It can also limit your productivity in school and in performing other important daily tasks. This does not mean that you should never play video games or watch television. The pictures are meant to indicate that it is good to limit screen time and to avoid being sedentary.
Inactivity, as used in the pyramid, doesn't include productive rest, such as sleep that allows recovery from the day's activities. For example, teens need at least 9 hours of sleep each day. As a teen you also need time for relaxation and productive light activities, such as reading and doing homework.
As noted earlier, to get all of the many benefits of physical activity, teens need to do 60 minutes of daily activity. Ideally you will do activities from each of the five steps each week. You will learn more about the formula for getting optimal benefits in later chapters of this book.
Fit Fact
Do You Sit Too Much?
Many teens spend more time watching TV and playing computer games than they do in school. Each day, you should spend at least as much time in moderate or vigorous activity as you do watching TV or playing inactive games.
Learn more about Fitness for Life: Middle School, Second Edition.
Why Should I Do Vigorous Aerobics?
Vigorous aerobic activities produce many of the same health and wellness benefits of moderate physical activities. One major benefit you get from vigorous aerobics that you can’t get from moderate physical activity is cardiorespiratory endurance.
Vigorous aerobic activities produce many of the same health and wellness benefits of moderate physical activities. One major benefit you get from vigorous aerobics that you can't get from moderate physical activity is cardiorespiratory endurance. In fact, vigorous aerobics is probably the best method of building good cardiorespiratory endurance. As you learned in chapter 1, cardiorespiratory endurance is the ability to perform exercise of your entire body for long periods of time without getting tired. It requires your heart, lungs, blood vessels, and blood to work efficiently and to supply the body with oxygen (figure 4.5). Some of the benefits of doing regular vigorous aerobics are explained in the following paragraphs.
Figure 4.5 Cardiorespiratory endurance requires fitness of many body systems.
Vigorous Aerobics and Cardiorespiratory Endurance for Sports
Teens interested in playing a sport should be very interested in vigorous aerobics because most sports require good cardiorespiratory endurance, and vigorous aerobics is a good way to get it. Sports such as cross-country running, track and field, skiing, swimming, soccer, and tennis are just a few that require cardiorespiratory endurance. You can't perform your best in sports unless you do activities that build good cardiorespiratory endurance.
Vigorous Aerobics and Cardiorespiratory Endurance for Health
Teens who do moderate physical activity get health benefits such as a reduced risk of developing certain diseases. Teens who also do vigorous aerobics get similar benefits and more! Vigorous aerobics can help you get out of the low fitness zone and into the healthy fitness zone for cardiorespiratory endurance.
Vigorous Aerobics and Cardiorespiratory Endurance for Wellness
Vigorous aerobics and the cardiorespiratory endurance that it produces help you to feel and look your best by burning calories and keeping off body fat. You'll feel your best because you'll be less tired. Best of all, you'll have fun because you'll be participating in activities that you enjoy.
Cardiorespiratory Endurance and Safety
In some special cases, people need to run to get help, shovel sand into sandbags, or even shovel snow for long periods of time. Good cardiorespiratory endurance would help a person to perform activities such as these.
Cardiorespiratory Endurance for Work
Certain jobs require cardiorespiratory endurance. For example, to get a job as a member of a fire or police department, you need good cardiorespiratory endurance. Park rangers, lifeguards, construction workers, ranchers, farmers, fitness instructors, and members of the military all must have good cardiorespiratory endurance. Any job that requires you to work for long periods of time and that causes your heart to beat fast requires good cardiorespiratory endurance.
Fit Fact
Blood Flow During Exercise
When you begin exercising, the blood vessels to your exercising muscles expand, and the blood vessels to your stomach and intestines contract. This increases the blood flow to your working muscles.
Firefighters and lifeguards must have good cardiorespiratory endurance.
© iStockphoto/Tim McCaig
Learn more about Fitness for Life: Middle School, Second Edition.
How Can I Assess My Body Composition?
Body fat is one important component of body composition. Ideally, people shouldn’t have too much or too little body fat. The goal is to be in the healthy fitness zone for your level of body fat.
Body fat is one important component of body composition. Ideally, people shouldn't have too much or too little body fat. The goal is to be in the healthy fitness zone for your level of body fat. The best methods of assessing a person's body fat level involve the use of X-ray machines and special water measurement tanks. These tests are expensive and can't be used quickly, so they aren't practical for general school classes. There are several methods of assessment that are commonly used in schools.
Some schools use a bioelectrical impedance analysis (BIA) machine to assess body fat levels (figure 8.3). Bioelectrical impedance machines have been shown to be quite accurate when used properly. The machine detects differences in water, lean body tissue, and fat, allowing it to estimate the amount of body fat that a person has. Schools that do not have BIA machines can use two other inexpensive methods: body mass index and skinfold measurements.
Figure 8.3 BIA machines can be used to assess body fat levels.
The most common body composition measurement used in schools is called the body mass index (BMI). As described in a special feature later in this lesson, you use your height and weight in a formula to calculate your BMI. The BMI doesn't directly assess body fat levels, but it does help you determine if you are in the healthy fitness zone. The BMI is a test commonly used in FitnessGram.
The BMI uses a formula to determine if you're overweight. The term overweight simply refers to having a BMI (combination of height and weight) that is higher than recommended for good health. Being overweight isn't the same as being high in body fat. It's possible to be high in weight without being too fat, because muscle weighs more than fat. People with a lot of muscle weigh more than people of the same size with less muscle. Even though there are limitations to the BMI, scientists indicate that people with a high BMI have more risk for heart disease, diabetes, and other chronic diseases than people with a BMI in the healthy fitness zone. A person who has an exceptionally high BMI without an exceptionally high amount of muscle or who has an exceptionally high amount of body fat is considered to be obese.
Fit Fact
Overweight in America
Two-thirds of adults and one-third of children and teens are considered to be either overweight or obese, resulting in increased chronic disease risk for many Americans.
Another method of assessing body composition is called skinfold measurements (figure 8.4). As shown in the photo, fat located under the skin is measured using a pair of skinfold calipers. The calipers are used to measure the thickness of fat folds beneath the skin. This test estimates the amount of fat in the body. Skinfold measurements are not as accurate as X-rays and underwater weighing, but they are often used because they give a good estimate of body fat levels and require only a relatively inexpensive pair of calipers and a trained person such as a teacher.
Figure 8.4 Calipers are used to make skinfold measurements.
The results of either the BMI or skinfold measurement tests will help you determine if you are in the healthy fitness zone. Your test results will show if you're in a zone that helps you function effectively and avoid problems associated with having too much or too little body fat or body weight.
Information about your body weight and body composition is personal. In fact, you have the right to treat all fitness testing results as private information. If people ask about your body weight, body composition, or other private information that you're not comfortable sharing, you can make a statement such as, "I don't feel comfortable sharing my personal information. Could you please respect my desire to keep personal information private?"
You should also help others keep their personal information private. For example, don't ask other people about their body weight or body composition. Also, if you work with a partner, keep that person's information private. In chapter 4, you learned some guidelines that you can use to build self-esteem. You may want to review those guidelines at this time.
You can take other steps to keep information confidential. One of the best ways is to share it only with people you trust, and only after asking them to keep the information private. Over time, you can build caring relationships with others, and this will reduce your need to worry about privacy. Sometimes, feeling comfortable in sharing information relieves the pressure of trying to keep things private.
Body Mass Index
Follow these steps and record your results.
- Measure your height in inches or meters without shoes.
- Measure your weight in pounds or kilograms without shoes. If you're wearing street clothes (as opposed to lightweight gym clothing), subtract 2 pounds or 1 kilogram from your weight.
- Use the body mass index chart to determine your BMI. You can also calculate your BMI using either of the following formulas:
BMI = weight in kilograms/(height in meters)2
BMI = weight in pounds/(height in inches)2 × 703
- Use table 8.1 to determine your rating for BMI.
Text adapted from C.B. Corbin and G.C. Le Masurier, 2014, Fitness for life, 6th ed. (Champaign, IL: Human Kinetics), 80.
| |
Height/Weight to BMI chart. Locate the row containing your height (left) and column containing your weight (bottom). The value in the box where rows and columns meet is your BMI.
Save
Save
Learn more about Fitness for Life: Middle School, Second Edition.
What Is Physical Activity?
Physical activity occurs when your muscles contract to make your body move. The national physical activity guidelines for teens recommend at least 60 minutes, and up to several hours, of physical activity each day of the week.
Physical activity occurs when your muscles contract to make your body move. The national physical activity guidelines for teens recommend at least 60 minutes, and up to several hours, of physical activity each day of the week. The guidelines recommend that teens perform a variety of activities. There are five basic types of physical activity from which you can choose to meet the national activity recommendation for youth. In this book the Physical Activity Pyramid for Teens is used to illustrate each of the different types of activities (see figure 1.2).
Figure 1.2 The Physical Activity Pyramid for Teens includes many types of activities.
© Charles Corbin
How Do I Know if I Am Active Enough?
In general you are active enough for good health if you meet the national teen guideline of 60 minutes or more of physical activity per day. However, the guidelines indicate that you should do a variety of activities and include some vigorous physical activity and some activity for building muscle fitness and for building strong bones. If you perform a variety of activities from the Physical Activity Pyramid you will meet the national guidelines. In the paragraphs that follow you will learn more about the pyramid.
There is a popular saying that "a picture is worth a thousand words." The saying means remembering a picture may be better than trying to remember a lot of words. So in this book the Physical Activity Pyramid picture is used to help you remember the five types of physical activity. Activities such as moderate physical activity are placed at the wide base of the pyramid because they typically are performed more regularly by people than activities higher in the pyramid. Activities at the bottom typically need to be performed more often than those higher in the pyramid to get benefits. The pyramid also has a triangle at the top that helps you remember the need for energy balance. Energy balance means expending as many calories in physical activity as the calories you consume in food. To get fitness, health, wellness, and energy balance you should choose activities from each of the five steps of the pyramid. You can combine activities from all five steps to meet the daily activity recommendation.
The first step in the pyramid includes moderate physical activities. The intensity of moderate activities is not too easy and not too hard. Any activity that is about as intense as walking briskly is considered moderate. One reason why moderate activities are placed at the bottom of the pyramid is that more people do moderate activity than any other type of activity. Moderate activities are also placed at the wide base of the pyramid because you get the best results when you do them on all or most days of the week. Activities at higher steps in the pyramid can be done less frequently and still provide important benefits.
Many moderate activities are sometimes referred to as lifestyle activities because you do them as part of your daily life. Examples include walking to school, working around the house, and working in the yard. Experts recommend that adults do moderate physical activity for 30 minutes or more each day. This is because activities from step 1 of the Physical Activity Pyramid help people reduce their risk of disease and help them maintain a healthy body weight. Some moderate activities are called lifetime activities because you can do them when you're young as well as when you grow older. Some activities from other steps of the pyramid are also considered to be lifetime activities. Examples include sports such as bowling and golf and recreational activities such as fishing because they're moderate in intensity. As you'll learn later in this book, it's recommended that teens do regular moderate activity to develop activity habits that can be used throughout life.
Vigorous aerobics is included in the second step of the Physical Activity Pyramid. Vigorous aerobics is a type of vigorous physical activity that is especially good for building cardiorespiratory endurance. The word aerobic means "with oxygen." In aerobic activities, your body supplies oxygen to keep you going. When your heart beats faster than normal during vigorous aerobics, your heart supplies your body with the oxygen it needs to keep going. Vigorous aerobics is the most popular type of vigorous physical activity for people of all ages. Examples of vigorous aerobics are running, swimming, in-line skating, aerobic dance, and biking at a vigorous intensity.
Vigorous sports and vigorous recreation at the third step of the pyramid also require your heart to beat faster and require you to breathe faster than normal. When done for at least 20 minutes at a time at least three days a week, these activities build cardiorespiratory endurance and provide health benefits similar to those provided by vigorous aerobics. Examples of vigorous sports are tennis, basketball, badminton, volleyball, and soccer. Examples of vigorous recreation are hiking, backpacking, and biking.
The word vigorous is used in combination with the terms aerobics, sports, and recreation when describing activities at the second and third steps of the pyramid to make it clear that activities at these steps are more intense than moderate activities. Moderate physical activities at the first step of the pyramid are also considered to be aerobic because your body can supply enough oxygen to allow you to keep doing these activities for long periods of time. But they're not considered to be vigorous because they're not intense enough to build optimal levels of cardiorespiratory endurance.
Exercise is a word used to refer to physical activity that is done with the specific purpose of building physical fitness. Muscle fitness exercises are included in the fourth step of the Physical Activity Pyramid for Teens. Muscle fitness exercises are designed to build all three parts of muscle fitness including strength, muscular endurance, and power. One reason why this type of exercise is placed higher in the pyramid than other types is that these exercises need not be performed every day to get benefits. Experts recommend that teens do muscle fitness exercises (such as curl-ups and push-ups) at least two days a week. Muscle fitness exercises help you to build strong bones, prevent muscle injury, and gain many of the same health benefits as with activities from steps 1 through 3.
Flexibility exercises build flexibility and help you to perform well in daily life activities and sport. They may also help reduce risk of injury. They are placed at step 5 of the pyramid. While they can be performed daily, you can maintain flexibility by performing them on two or three days per week.
At the very top of the pyramid is a balance scale. This scale helps show the importance of energy balance. As noted earlier in this lesson, energy balance means that the calories in the food you eat each day are equal to the calories you expend in exercise each day. You must achieve energy balance in order to maintain a healthy body composition. Activities from all steps of the pyramid expend energy and help you balance energy.
At the bottom of the teen physical pyramid are two small pictures with big cross marks over them. One picture is of a video game controller and the other is a picture of a television set. The pictures are meant to caution against being inactive. Being inactive or sedentary isn't good for your health or fitness. It can also limit your productivity in school and in performing other important daily tasks. This does not mean that you should never play video games or watch television. The pictures are meant to indicate that it is good to limit screen time and to avoid being sedentary.
Inactivity, as used in the pyramid, doesn't include productive rest, such as sleep that allows recovery from the day's activities. For example, teens need at least 9 hours of sleep each day. As a teen you also need time for relaxation and productive light activities, such as reading and doing homework.
As noted earlier, to get all of the many benefits of physical activity, teens need to do 60 minutes of daily activity. Ideally you will do activities from each of the five steps each week. You will learn more about the formula for getting optimal benefits in later chapters of this book.
Fit Fact
Do You Sit Too Much?
Many teens spend more time watching TV and playing computer games than they do in school. Each day, you should spend at least as much time in moderate or vigorous activity as you do watching TV or playing inactive games.
Learn more about Fitness for Life: Middle School, Second Edition.
Why Should I Do Vigorous Aerobics?
Vigorous aerobic activities produce many of the same health and wellness benefits of moderate physical activities. One major benefit you get from vigorous aerobics that you can’t get from moderate physical activity is cardiorespiratory endurance.
Vigorous aerobic activities produce many of the same health and wellness benefits of moderate physical activities. One major benefit you get from vigorous aerobics that you can't get from moderate physical activity is cardiorespiratory endurance. In fact, vigorous aerobics is probably the best method of building good cardiorespiratory endurance. As you learned in chapter 1, cardiorespiratory endurance is the ability to perform exercise of your entire body for long periods of time without getting tired. It requires your heart, lungs, blood vessels, and blood to work efficiently and to supply the body with oxygen (figure 4.5). Some of the benefits of doing regular vigorous aerobics are explained in the following paragraphs.
Figure 4.5 Cardiorespiratory endurance requires fitness of many body systems.
Vigorous Aerobics and Cardiorespiratory Endurance for Sports
Teens interested in playing a sport should be very interested in vigorous aerobics because most sports require good cardiorespiratory endurance, and vigorous aerobics is a good way to get it. Sports such as cross-country running, track and field, skiing, swimming, soccer, and tennis are just a few that require cardiorespiratory endurance. You can't perform your best in sports unless you do activities that build good cardiorespiratory endurance.
Vigorous Aerobics and Cardiorespiratory Endurance for Health
Teens who do moderate physical activity get health benefits such as a reduced risk of developing certain diseases. Teens who also do vigorous aerobics get similar benefits and more! Vigorous aerobics can help you get out of the low fitness zone and into the healthy fitness zone for cardiorespiratory endurance.
Vigorous Aerobics and Cardiorespiratory Endurance for Wellness
Vigorous aerobics and the cardiorespiratory endurance that it produces help you to feel and look your best by burning calories and keeping off body fat. You'll feel your best because you'll be less tired. Best of all, you'll have fun because you'll be participating in activities that you enjoy.
Cardiorespiratory Endurance and Safety
In some special cases, people need to run to get help, shovel sand into sandbags, or even shovel snow for long periods of time. Good cardiorespiratory endurance would help a person to perform activities such as these.
Cardiorespiratory Endurance for Work
Certain jobs require cardiorespiratory endurance. For example, to get a job as a member of a fire or police department, you need good cardiorespiratory endurance. Park rangers, lifeguards, construction workers, ranchers, farmers, fitness instructors, and members of the military all must have good cardiorespiratory endurance. Any job that requires you to work for long periods of time and that causes your heart to beat fast requires good cardiorespiratory endurance.
Fit Fact
Blood Flow During Exercise
When you begin exercising, the blood vessels to your exercising muscles expand, and the blood vessels to your stomach and intestines contract. This increases the blood flow to your working muscles.
Firefighters and lifeguards must have good cardiorespiratory endurance.
© iStockphoto/Tim McCaig
Learn more about Fitness for Life: Middle School, Second Edition.
How Can I Assess My Body Composition?
Body fat is one important component of body composition. Ideally, people shouldn’t have too much or too little body fat. The goal is to be in the healthy fitness zone for your level of body fat.
Body fat is one important component of body composition. Ideally, people shouldn't have too much or too little body fat. The goal is to be in the healthy fitness zone for your level of body fat. The best methods of assessing a person's body fat level involve the use of X-ray machines and special water measurement tanks. These tests are expensive and can't be used quickly, so they aren't practical for general school classes. There are several methods of assessment that are commonly used in schools.
Some schools use a bioelectrical impedance analysis (BIA) machine to assess body fat levels (figure 8.3). Bioelectrical impedance machines have been shown to be quite accurate when used properly. The machine detects differences in water, lean body tissue, and fat, allowing it to estimate the amount of body fat that a person has. Schools that do not have BIA machines can use two other inexpensive methods: body mass index and skinfold measurements.
Figure 8.3 BIA machines can be used to assess body fat levels.
The most common body composition measurement used in schools is called the body mass index (BMI). As described in a special feature later in this lesson, you use your height and weight in a formula to calculate your BMI. The BMI doesn't directly assess body fat levels, but it does help you determine if you are in the healthy fitness zone. The BMI is a test commonly used in FitnessGram.
The BMI uses a formula to determine if you're overweight. The term overweight simply refers to having a BMI (combination of height and weight) that is higher than recommended for good health. Being overweight isn't the same as being high in body fat. It's possible to be high in weight without being too fat, because muscle weighs more than fat. People with a lot of muscle weigh more than people of the same size with less muscle. Even though there are limitations to the BMI, scientists indicate that people with a high BMI have more risk for heart disease, diabetes, and other chronic diseases than people with a BMI in the healthy fitness zone. A person who has an exceptionally high BMI without an exceptionally high amount of muscle or who has an exceptionally high amount of body fat is considered to be obese.
Fit Fact
Overweight in America
Two-thirds of adults and one-third of children and teens are considered to be either overweight or obese, resulting in increased chronic disease risk for many Americans.
Another method of assessing body composition is called skinfold measurements (figure 8.4). As shown in the photo, fat located under the skin is measured using a pair of skinfold calipers. The calipers are used to measure the thickness of fat folds beneath the skin. This test estimates the amount of fat in the body. Skinfold measurements are not as accurate as X-rays and underwater weighing, but they are often used because they give a good estimate of body fat levels and require only a relatively inexpensive pair of calipers and a trained person such as a teacher.
Figure 8.4 Calipers are used to make skinfold measurements.
The results of either the BMI or skinfold measurement tests will help you determine if you are in the healthy fitness zone. Your test results will show if you're in a zone that helps you function effectively and avoid problems associated with having too much or too little body fat or body weight.
Information about your body weight and body composition is personal. In fact, you have the right to treat all fitness testing results as private information. If people ask about your body weight, body composition, or other private information that you're not comfortable sharing, you can make a statement such as, "I don't feel comfortable sharing my personal information. Could you please respect my desire to keep personal information private?"
You should also help others keep their personal information private. For example, don't ask other people about their body weight or body composition. Also, if you work with a partner, keep that person's information private. In chapter 4, you learned some guidelines that you can use to build self-esteem. You may want to review those guidelines at this time.
You can take other steps to keep information confidential. One of the best ways is to share it only with people you trust, and only after asking them to keep the information private. Over time, you can build caring relationships with others, and this will reduce your need to worry about privacy. Sometimes, feeling comfortable in sharing information relieves the pressure of trying to keep things private.
Body Mass Index
Follow these steps and record your results.
- Measure your height in inches or meters without shoes.
- Measure your weight in pounds or kilograms without shoes. If you're wearing street clothes (as opposed to lightweight gym clothing), subtract 2 pounds or 1 kilogram from your weight.
- Use the body mass index chart to determine your BMI. You can also calculate your BMI using either of the following formulas:
BMI = weight in kilograms/(height in meters)2
BMI = weight in pounds/(height in inches)2 × 703
- Use table 8.1 to determine your rating for BMI.
Text adapted from C.B. Corbin and G.C. Le Masurier, 2014, Fitness for life, 6th ed. (Champaign, IL: Human Kinetics), 80.
| |
Height/Weight to BMI chart. Locate the row containing your height (left) and column containing your weight (bottom). The value in the box where rows and columns meet is your BMI.
Save
Save
Learn more about Fitness for Life: Middle School, Second Edition.
What Is Physical Activity?
Physical activity occurs when your muscles contract to make your body move. The national physical activity guidelines for teens recommend at least 60 minutes, and up to several hours, of physical activity each day of the week.
Physical activity occurs when your muscles contract to make your body move. The national physical activity guidelines for teens recommend at least 60 minutes, and up to several hours, of physical activity each day of the week. The guidelines recommend that teens perform a variety of activities. There are five basic types of physical activity from which you can choose to meet the national activity recommendation for youth. In this book the Physical Activity Pyramid for Teens is used to illustrate each of the different types of activities (see figure 1.2).
Figure 1.2 The Physical Activity Pyramid for Teens includes many types of activities.
© Charles Corbin
How Do I Know if I Am Active Enough?
In general you are active enough for good health if you meet the national teen guideline of 60 minutes or more of physical activity per day. However, the guidelines indicate that you should do a variety of activities and include some vigorous physical activity and some activity for building muscle fitness and for building strong bones. If you perform a variety of activities from the Physical Activity Pyramid you will meet the national guidelines. In the paragraphs that follow you will learn more about the pyramid.
There is a popular saying that "a picture is worth a thousand words." The saying means remembering a picture may be better than trying to remember a lot of words. So in this book the Physical Activity Pyramid picture is used to help you remember the five types of physical activity. Activities such as moderate physical activity are placed at the wide base of the pyramid because they typically are performed more regularly by people than activities higher in the pyramid. Activities at the bottom typically need to be performed more often than those higher in the pyramid to get benefits. The pyramid also has a triangle at the top that helps you remember the need for energy balance. Energy balance means expending as many calories in physical activity as the calories you consume in food. To get fitness, health, wellness, and energy balance you should choose activities from each of the five steps of the pyramid. You can combine activities from all five steps to meet the daily activity recommendation.
The first step in the pyramid includes moderate physical activities. The intensity of moderate activities is not too easy and not too hard. Any activity that is about as intense as walking briskly is considered moderate. One reason why moderate activities are placed at the bottom of the pyramid is that more people do moderate activity than any other type of activity. Moderate activities are also placed at the wide base of the pyramid because you get the best results when you do them on all or most days of the week. Activities at higher steps in the pyramid can be done less frequently and still provide important benefits.
Many moderate activities are sometimes referred to as lifestyle activities because you do them as part of your daily life. Examples include walking to school, working around the house, and working in the yard. Experts recommend that adults do moderate physical activity for 30 minutes or more each day. This is because activities from step 1 of the Physical Activity Pyramid help people reduce their risk of disease and help them maintain a healthy body weight. Some moderate activities are called lifetime activities because you can do them when you're young as well as when you grow older. Some activities from other steps of the pyramid are also considered to be lifetime activities. Examples include sports such as bowling and golf and recreational activities such as fishing because they're moderate in intensity. As you'll learn later in this book, it's recommended that teens do regular moderate activity to develop activity habits that can be used throughout life.
Vigorous aerobics is included in the second step of the Physical Activity Pyramid. Vigorous aerobics is a type of vigorous physical activity that is especially good for building cardiorespiratory endurance. The word aerobic means "with oxygen." In aerobic activities, your body supplies oxygen to keep you going. When your heart beats faster than normal during vigorous aerobics, your heart supplies your body with the oxygen it needs to keep going. Vigorous aerobics is the most popular type of vigorous physical activity for people of all ages. Examples of vigorous aerobics are running, swimming, in-line skating, aerobic dance, and biking at a vigorous intensity.
Vigorous sports and vigorous recreation at the third step of the pyramid also require your heart to beat faster and require you to breathe faster than normal. When done for at least 20 minutes at a time at least three days a week, these activities build cardiorespiratory endurance and provide health benefits similar to those provided by vigorous aerobics. Examples of vigorous sports are tennis, basketball, badminton, volleyball, and soccer. Examples of vigorous recreation are hiking, backpacking, and biking.
The word vigorous is used in combination with the terms aerobics, sports, and recreation when describing activities at the second and third steps of the pyramid to make it clear that activities at these steps are more intense than moderate activities. Moderate physical activities at the first step of the pyramid are also considered to be aerobic because your body can supply enough oxygen to allow you to keep doing these activities for long periods of time. But they're not considered to be vigorous because they're not intense enough to build optimal levels of cardiorespiratory endurance.
Exercise is a word used to refer to physical activity that is done with the specific purpose of building physical fitness. Muscle fitness exercises are included in the fourth step of the Physical Activity Pyramid for Teens. Muscle fitness exercises are designed to build all three parts of muscle fitness including strength, muscular endurance, and power. One reason why this type of exercise is placed higher in the pyramid than other types is that these exercises need not be performed every day to get benefits. Experts recommend that teens do muscle fitness exercises (such as curl-ups and push-ups) at least two days a week. Muscle fitness exercises help you to build strong bones, prevent muscle injury, and gain many of the same health benefits as with activities from steps 1 through 3.
Flexibility exercises build flexibility and help you to perform well in daily life activities and sport. They may also help reduce risk of injury. They are placed at step 5 of the pyramid. While they can be performed daily, you can maintain flexibility by performing them on two or three days per week.
At the very top of the pyramid is a balance scale. This scale helps show the importance of energy balance. As noted earlier in this lesson, energy balance means that the calories in the food you eat each day are equal to the calories you expend in exercise each day. You must achieve energy balance in order to maintain a healthy body composition. Activities from all steps of the pyramid expend energy and help you balance energy.
At the bottom of the teen physical pyramid are two small pictures with big cross marks over them. One picture is of a video game controller and the other is a picture of a television set. The pictures are meant to caution against being inactive. Being inactive or sedentary isn't good for your health or fitness. It can also limit your productivity in school and in performing other important daily tasks. This does not mean that you should never play video games or watch television. The pictures are meant to indicate that it is good to limit screen time and to avoid being sedentary.
Inactivity, as used in the pyramid, doesn't include productive rest, such as sleep that allows recovery from the day's activities. For example, teens need at least 9 hours of sleep each day. As a teen you also need time for relaxation and productive light activities, such as reading and doing homework.
As noted earlier, to get all of the many benefits of physical activity, teens need to do 60 minutes of daily activity. Ideally you will do activities from each of the five steps each week. You will learn more about the formula for getting optimal benefits in later chapters of this book.
Fit Fact
Do You Sit Too Much?
Many teens spend more time watching TV and playing computer games than they do in school. Each day, you should spend at least as much time in moderate or vigorous activity as you do watching TV or playing inactive games.
Learn more about Fitness for Life: Middle School, Second Edition.
Why Should I Do Vigorous Aerobics?
Vigorous aerobic activities produce many of the same health and wellness benefits of moderate physical activities. One major benefit you get from vigorous aerobics that you can’t get from moderate physical activity is cardiorespiratory endurance.
Vigorous aerobic activities produce many of the same health and wellness benefits of moderate physical activities. One major benefit you get from vigorous aerobics that you can't get from moderate physical activity is cardiorespiratory endurance. In fact, vigorous aerobics is probably the best method of building good cardiorespiratory endurance. As you learned in chapter 1, cardiorespiratory endurance is the ability to perform exercise of your entire body for long periods of time without getting tired. It requires your heart, lungs, blood vessels, and blood to work efficiently and to supply the body with oxygen (figure 4.5). Some of the benefits of doing regular vigorous aerobics are explained in the following paragraphs.
Figure 4.5 Cardiorespiratory endurance requires fitness of many body systems.
Vigorous Aerobics and Cardiorespiratory Endurance for Sports
Teens interested in playing a sport should be very interested in vigorous aerobics because most sports require good cardiorespiratory endurance, and vigorous aerobics is a good way to get it. Sports such as cross-country running, track and field, skiing, swimming, soccer, and tennis are just a few that require cardiorespiratory endurance. You can't perform your best in sports unless you do activities that build good cardiorespiratory endurance.
Vigorous Aerobics and Cardiorespiratory Endurance for Health
Teens who do moderate physical activity get health benefits such as a reduced risk of developing certain diseases. Teens who also do vigorous aerobics get similar benefits and more! Vigorous aerobics can help you get out of the low fitness zone and into the healthy fitness zone for cardiorespiratory endurance.
Vigorous Aerobics and Cardiorespiratory Endurance for Wellness
Vigorous aerobics and the cardiorespiratory endurance that it produces help you to feel and look your best by burning calories and keeping off body fat. You'll feel your best because you'll be less tired. Best of all, you'll have fun because you'll be participating in activities that you enjoy.
Cardiorespiratory Endurance and Safety
In some special cases, people need to run to get help, shovel sand into sandbags, or even shovel snow for long periods of time. Good cardiorespiratory endurance would help a person to perform activities such as these.
Cardiorespiratory Endurance for Work
Certain jobs require cardiorespiratory endurance. For example, to get a job as a member of a fire or police department, you need good cardiorespiratory endurance. Park rangers, lifeguards, construction workers, ranchers, farmers, fitness instructors, and members of the military all must have good cardiorespiratory endurance. Any job that requires you to work for long periods of time and that causes your heart to beat fast requires good cardiorespiratory endurance.
Fit Fact
Blood Flow During Exercise
When you begin exercising, the blood vessels to your exercising muscles expand, and the blood vessels to your stomach and intestines contract. This increases the blood flow to your working muscles.
Firefighters and lifeguards must have good cardiorespiratory endurance.
© iStockphoto/Tim McCaig
Learn more about Fitness for Life: Middle School, Second Edition.
How Can I Assess My Body Composition?
Body fat is one important component of body composition. Ideally, people shouldn’t have too much or too little body fat. The goal is to be in the healthy fitness zone for your level of body fat.
Body fat is one important component of body composition. Ideally, people shouldn't have too much or too little body fat. The goal is to be in the healthy fitness zone for your level of body fat. The best methods of assessing a person's body fat level involve the use of X-ray machines and special water measurement tanks. These tests are expensive and can't be used quickly, so they aren't practical for general school classes. There are several methods of assessment that are commonly used in schools.
Some schools use a bioelectrical impedance analysis (BIA) machine to assess body fat levels (figure 8.3). Bioelectrical impedance machines have been shown to be quite accurate when used properly. The machine detects differences in water, lean body tissue, and fat, allowing it to estimate the amount of body fat that a person has. Schools that do not have BIA machines can use two other inexpensive methods: body mass index and skinfold measurements.
Figure 8.3 BIA machines can be used to assess body fat levels.
The most common body composition measurement used in schools is called the body mass index (BMI). As described in a special feature later in this lesson, you use your height and weight in a formula to calculate your BMI. The BMI doesn't directly assess body fat levels, but it does help you determine if you are in the healthy fitness zone. The BMI is a test commonly used in FitnessGram.
The BMI uses a formula to determine if you're overweight. The term overweight simply refers to having a BMI (combination of height and weight) that is higher than recommended for good health. Being overweight isn't the same as being high in body fat. It's possible to be high in weight without being too fat, because muscle weighs more than fat. People with a lot of muscle weigh more than people of the same size with less muscle. Even though there are limitations to the BMI, scientists indicate that people with a high BMI have more risk for heart disease, diabetes, and other chronic diseases than people with a BMI in the healthy fitness zone. A person who has an exceptionally high BMI without an exceptionally high amount of muscle or who has an exceptionally high amount of body fat is considered to be obese.
Fit Fact
Overweight in America
Two-thirds of adults and one-third of children and teens are considered to be either overweight or obese, resulting in increased chronic disease risk for many Americans.
Another method of assessing body composition is called skinfold measurements (figure 8.4). As shown in the photo, fat located under the skin is measured using a pair of skinfold calipers. The calipers are used to measure the thickness of fat folds beneath the skin. This test estimates the amount of fat in the body. Skinfold measurements are not as accurate as X-rays and underwater weighing, but they are often used because they give a good estimate of body fat levels and require only a relatively inexpensive pair of calipers and a trained person such as a teacher.
Figure 8.4 Calipers are used to make skinfold measurements.
The results of either the BMI or skinfold measurement tests will help you determine if you are in the healthy fitness zone. Your test results will show if you're in a zone that helps you function effectively and avoid problems associated with having too much or too little body fat or body weight.
Information about your body weight and body composition is personal. In fact, you have the right to treat all fitness testing results as private information. If people ask about your body weight, body composition, or other private information that you're not comfortable sharing, you can make a statement such as, "I don't feel comfortable sharing my personal information. Could you please respect my desire to keep personal information private?"
You should also help others keep their personal information private. For example, don't ask other people about their body weight or body composition. Also, if you work with a partner, keep that person's information private. In chapter 4, you learned some guidelines that you can use to build self-esteem. You may want to review those guidelines at this time.
You can take other steps to keep information confidential. One of the best ways is to share it only with people you trust, and only after asking them to keep the information private. Over time, you can build caring relationships with others, and this will reduce your need to worry about privacy. Sometimes, feeling comfortable in sharing information relieves the pressure of trying to keep things private.
Body Mass Index
Follow these steps and record your results.
- Measure your height in inches or meters without shoes.
- Measure your weight in pounds or kilograms without shoes. If you're wearing street clothes (as opposed to lightweight gym clothing), subtract 2 pounds or 1 kilogram from your weight.
- Use the body mass index chart to determine your BMI. You can also calculate your BMI using either of the following formulas:
BMI = weight in kilograms/(height in meters)2
BMI = weight in pounds/(height in inches)2 × 703
- Use table 8.1 to determine your rating for BMI.
Text adapted from C.B. Corbin and G.C. Le Masurier, 2014, Fitness for life, 6th ed. (Champaign, IL: Human Kinetics), 80.
| |
Height/Weight to BMI chart. Locate the row containing your height (left) and column containing your weight (bottom). The value in the box where rows and columns meet is your BMI.
Save
Save
Learn more about Fitness for Life: Middle School, Second Edition.
What Is Physical Activity?
Physical activity occurs when your muscles contract to make your body move. The national physical activity guidelines for teens recommend at least 60 minutes, and up to several hours, of physical activity each day of the week.
Physical activity occurs when your muscles contract to make your body move. The national physical activity guidelines for teens recommend at least 60 minutes, and up to several hours, of physical activity each day of the week. The guidelines recommend that teens perform a variety of activities. There are five basic types of physical activity from which you can choose to meet the national activity recommendation for youth. In this book the Physical Activity Pyramid for Teens is used to illustrate each of the different types of activities (see figure 1.2).
Figure 1.2 The Physical Activity Pyramid for Teens includes many types of activities.
© Charles Corbin
How Do I Know if I Am Active Enough?
In general you are active enough for good health if you meet the national teen guideline of 60 minutes or more of physical activity per day. However, the guidelines indicate that you should do a variety of activities and include some vigorous physical activity and some activity for building muscle fitness and for building strong bones. If you perform a variety of activities from the Physical Activity Pyramid you will meet the national guidelines. In the paragraphs that follow you will learn more about the pyramid.
There is a popular saying that "a picture is worth a thousand words." The saying means remembering a picture may be better than trying to remember a lot of words. So in this book the Physical Activity Pyramid picture is used to help you remember the five types of physical activity. Activities such as moderate physical activity are placed at the wide base of the pyramid because they typically are performed more regularly by people than activities higher in the pyramid. Activities at the bottom typically need to be performed more often than those higher in the pyramid to get benefits. The pyramid also has a triangle at the top that helps you remember the need for energy balance. Energy balance means expending as many calories in physical activity as the calories you consume in food. To get fitness, health, wellness, and energy balance you should choose activities from each of the five steps of the pyramid. You can combine activities from all five steps to meet the daily activity recommendation.
The first step in the pyramid includes moderate physical activities. The intensity of moderate activities is not too easy and not too hard. Any activity that is about as intense as walking briskly is considered moderate. One reason why moderate activities are placed at the bottom of the pyramid is that more people do moderate activity than any other type of activity. Moderate activities are also placed at the wide base of the pyramid because you get the best results when you do them on all or most days of the week. Activities at higher steps in the pyramid can be done less frequently and still provide important benefits.
Many moderate activities are sometimes referred to as lifestyle activities because you do them as part of your daily life. Examples include walking to school, working around the house, and working in the yard. Experts recommend that adults do moderate physical activity for 30 minutes or more each day. This is because activities from step 1 of the Physical Activity Pyramid help people reduce their risk of disease and help them maintain a healthy body weight. Some moderate activities are called lifetime activities because you can do them when you're young as well as when you grow older. Some activities from other steps of the pyramid are also considered to be lifetime activities. Examples include sports such as bowling and golf and recreational activities such as fishing because they're moderate in intensity. As you'll learn later in this book, it's recommended that teens do regular moderate activity to develop activity habits that can be used throughout life.
Vigorous aerobics is included in the second step of the Physical Activity Pyramid. Vigorous aerobics is a type of vigorous physical activity that is especially good for building cardiorespiratory endurance. The word aerobic means "with oxygen." In aerobic activities, your body supplies oxygen to keep you going. When your heart beats faster than normal during vigorous aerobics, your heart supplies your body with the oxygen it needs to keep going. Vigorous aerobics is the most popular type of vigorous physical activity for people of all ages. Examples of vigorous aerobics are running, swimming, in-line skating, aerobic dance, and biking at a vigorous intensity.
Vigorous sports and vigorous recreation at the third step of the pyramid also require your heart to beat faster and require you to breathe faster than normal. When done for at least 20 minutes at a time at least three days a week, these activities build cardiorespiratory endurance and provide health benefits similar to those provided by vigorous aerobics. Examples of vigorous sports are tennis, basketball, badminton, volleyball, and soccer. Examples of vigorous recreation are hiking, backpacking, and biking.
The word vigorous is used in combination with the terms aerobics, sports, and recreation when describing activities at the second and third steps of the pyramid to make it clear that activities at these steps are more intense than moderate activities. Moderate physical activities at the first step of the pyramid are also considered to be aerobic because your body can supply enough oxygen to allow you to keep doing these activities for long periods of time. But they're not considered to be vigorous because they're not intense enough to build optimal levels of cardiorespiratory endurance.
Exercise is a word used to refer to physical activity that is done with the specific purpose of building physical fitness. Muscle fitness exercises are included in the fourth step of the Physical Activity Pyramid for Teens. Muscle fitness exercises are designed to build all three parts of muscle fitness including strength, muscular endurance, and power. One reason why this type of exercise is placed higher in the pyramid than other types is that these exercises need not be performed every day to get benefits. Experts recommend that teens do muscle fitness exercises (such as curl-ups and push-ups) at least two days a week. Muscle fitness exercises help you to build strong bones, prevent muscle injury, and gain many of the same health benefits as with activities from steps 1 through 3.
Flexibility exercises build flexibility and help you to perform well in daily life activities and sport. They may also help reduce risk of injury. They are placed at step 5 of the pyramid. While they can be performed daily, you can maintain flexibility by performing them on two or three days per week.
At the very top of the pyramid is a balance scale. This scale helps show the importance of energy balance. As noted earlier in this lesson, energy balance means that the calories in the food you eat each day are equal to the calories you expend in exercise each day. You must achieve energy balance in order to maintain a healthy body composition. Activities from all steps of the pyramid expend energy and help you balance energy.
At the bottom of the teen physical pyramid are two small pictures with big cross marks over them. One picture is of a video game controller and the other is a picture of a television set. The pictures are meant to caution against being inactive. Being inactive or sedentary isn't good for your health or fitness. It can also limit your productivity in school and in performing other important daily tasks. This does not mean that you should never play video games or watch television. The pictures are meant to indicate that it is good to limit screen time and to avoid being sedentary.
Inactivity, as used in the pyramid, doesn't include productive rest, such as sleep that allows recovery from the day's activities. For example, teens need at least 9 hours of sleep each day. As a teen you also need time for relaxation and productive light activities, such as reading and doing homework.
As noted earlier, to get all of the many benefits of physical activity, teens need to do 60 minutes of daily activity. Ideally you will do activities from each of the five steps each week. You will learn more about the formula for getting optimal benefits in later chapters of this book.
Fit Fact
Do You Sit Too Much?
Many teens spend more time watching TV and playing computer games than they do in school. Each day, you should spend at least as much time in moderate or vigorous activity as you do watching TV or playing inactive games.
Learn more about Fitness for Life: Middle School, Second Edition.
Why Should I Do Vigorous Aerobics?
Vigorous aerobic activities produce many of the same health and wellness benefits of moderate physical activities. One major benefit you get from vigorous aerobics that you can’t get from moderate physical activity is cardiorespiratory endurance.
Vigorous aerobic activities produce many of the same health and wellness benefits of moderate physical activities. One major benefit you get from vigorous aerobics that you can't get from moderate physical activity is cardiorespiratory endurance. In fact, vigorous aerobics is probably the best method of building good cardiorespiratory endurance. As you learned in chapter 1, cardiorespiratory endurance is the ability to perform exercise of your entire body for long periods of time without getting tired. It requires your heart, lungs, blood vessels, and blood to work efficiently and to supply the body with oxygen (figure 4.5). Some of the benefits of doing regular vigorous aerobics are explained in the following paragraphs.
Figure 4.5 Cardiorespiratory endurance requires fitness of many body systems.
Vigorous Aerobics and Cardiorespiratory Endurance for Sports
Teens interested in playing a sport should be very interested in vigorous aerobics because most sports require good cardiorespiratory endurance, and vigorous aerobics is a good way to get it. Sports such as cross-country running, track and field, skiing, swimming, soccer, and tennis are just a few that require cardiorespiratory endurance. You can't perform your best in sports unless you do activities that build good cardiorespiratory endurance.
Vigorous Aerobics and Cardiorespiratory Endurance for Health
Teens who do moderate physical activity get health benefits such as a reduced risk of developing certain diseases. Teens who also do vigorous aerobics get similar benefits and more! Vigorous aerobics can help you get out of the low fitness zone and into the healthy fitness zone for cardiorespiratory endurance.
Vigorous Aerobics and Cardiorespiratory Endurance for Wellness
Vigorous aerobics and the cardiorespiratory endurance that it produces help you to feel and look your best by burning calories and keeping off body fat. You'll feel your best because you'll be less tired. Best of all, you'll have fun because you'll be participating in activities that you enjoy.
Cardiorespiratory Endurance and Safety
In some special cases, people need to run to get help, shovel sand into sandbags, or even shovel snow for long periods of time. Good cardiorespiratory endurance would help a person to perform activities such as these.
Cardiorespiratory Endurance for Work
Certain jobs require cardiorespiratory endurance. For example, to get a job as a member of a fire or police department, you need good cardiorespiratory endurance. Park rangers, lifeguards, construction workers, ranchers, farmers, fitness instructors, and members of the military all must have good cardiorespiratory endurance. Any job that requires you to work for long periods of time and that causes your heart to beat fast requires good cardiorespiratory endurance.
Fit Fact
Blood Flow During Exercise
When you begin exercising, the blood vessels to your exercising muscles expand, and the blood vessels to your stomach and intestines contract. This increases the blood flow to your working muscles.
Firefighters and lifeguards must have good cardiorespiratory endurance.
© iStockphoto/Tim McCaig
Learn more about Fitness for Life: Middle School, Second Edition.
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