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This page features questions about Fitness for Life: Middle School sent in by students and answered by the authors. We’ll post new questions and answers on March 1, June 1, September 1, and December 1 of each year. The authors will try to answer all questions that are submitted, but when volume is high, they might answer only a select number of questions. When choosing questions, the authors will give priority to those that don’t repeat topics from questions that have already been addressed.

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Q:I want to keep track of the steps I take each day. How many steps should a seventh grader take?

A:On page 28 of your Fitness for Life: Middle School textbook, the national physical activity guidelines for youth (including seventh graders and other middle school youth) are described. They indicate that people your age need 60 minutes to several hours of physical activity each day. The guidelines do not suggest a specific number of steps. However, using a pedometer to count steps (see page 29 of your book) can be a good way to self-monitor (keep track of) your daily activity.

A study of youth found that younger middle school boys average about 13,000 steps a day while younger middle school girls average about 11,000 steps a day. Older middle school boys (11,000 steps per day) and girls (10,000 steps per day) average fewer steps per day than younger middle school youth. You can earn the President’s Council on Physical Fitness and Sports Active Lifestyle Award by taking 13,000 (boys) or 11,000 (girls) steps per day for five days a week for six weeks (see www.presidentschallenge.org/the_challenge/active_lifestyle.aspx).

Most experts agree that you should not start by setting high goals such as those for the Active Lifestyle Award. The best way to start is to keep a record of the steps you take each day (using a pedometer) for one week. At the end of the week, determine your average steps per day. Then set a goal for the next week of 1,000 more steps per day than the average of the week before. You can continue to increase each week until you average about 12,000 steps or higher. Then you may want to consider trying to earn the Active Lifestyle Award.

Some people have asked why the President’s Council set the number of steps for boys at a higher level than for girls. The answer is that the average boy takes more steps than the average girl. There is no reason why girls cannot be as active as boys, and there is no reason why girls cannot aim for the same standards as boys. Whether you are a boy or a girl, it is best to start gradually and increase your goal as you improve.

Corbin, C.B., R.P. Pangrazi, and G.C. Le Masurier. 2004. Physical activity for children: Current patterns and guidelines. President’s Council for Physical Fitness and Sports Research Digest, 5(2): 1-8.

Strong, W.B., et al. 2005. Evidence based physical activity for school-aged youth. Journal of Pediatrics 146: 732-737.

National Association for Sport and Physical Education. 2004. Physical activity for children: A statement of guidelines for children 5-12. 2nd ed. Reston, VA: NASPE.


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Q:In the book, we learned about practice. If you practice, you get better. Is there such a thing as too much practice?

A:Yes, there is such a thing as too much practice. In the book, you learned that perfect or good practice helps you learn skills. Practicing or repeating a skill the wrong way doesn’t help because you’re learning the skill incorrectly. If you practice for too long all at once, you can become fatigued, and your good practice turns into bad practice. When you get tired, you start to make mistakes, and that makes your practice ineffective. Also, if you get bored with practice, you might start to practice a skill incorrectly.

This doesn’t mean that you should always stop practicing when you get tired. During a game, you often have to perform skills when you’re tired. For example, late in a basketball game, you might have to shoot when you’re tired. So practicing shooting when you’re a bit tired can help you shoot well in a game when you’re tired.

The important thing to remember is to focus on good practice when you start to get tired or bored. If the practice is not good practice, find a way to practice correctly or stop the practice until you can concentrate better. Practicing one skill for a while and then another for a while can help you keep from getting bored and can help you practice well, even when you’re tired. However, if you’re too tired to practice properly, stop your practice and try again at another time.


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Q:Why do you recommend 10-15 repetitions for muscular strength and 11-25 reps for muscular endurance for middle school age youth?

A:The overload principle (described in your textbook on p. 79) provides the basis for determining the amount of exercise necessary to build muscle fitness. The amount of resistance exercise recommended for building muscle fitness varies depending on age. ACSM's Guidelines for Exercise Testing & Prescription, which provides recommendations for adults, notes that 3-6 repetitions of heavy resistance can be used at one extreme and more repetitions at lighter resistance (8-12) can be used at the other extreme (ACSM 2006, p. 155). The guidelines (p. 156) suggest that to elicit improvement in both muscular strength and endurance, 8-12 repetitions at an intensity that results in muscular fatigue is recommended for healthy adults. For youth, it is generally suggested that lighter resistance (weight) should be used, especially for younger teens. A summary of the literature by Faigenbaum resulted in the recommendation of 10-15 repetitions for youth rather than 8-12 as recommended for adults. For exercises that use body weight as resistance, such as curl-ups and push-ups, or exercises with very light resistance, up to 25 repetitions can be used (with a focus more on muscular endurance than strength). More than 25 repetitions of an exercise would only be possible with very low resistance and would be of limited value for building muscle fitness. If muscle fitness is the goal, a lower number of repetitions with a higher resistance is recommended.

Of course, depending on a person's level of fitness, the amount of resistance training will vary. For example, it is recommended that teens who are beginning resistance training start with lower resistance and a higher number of repetitions. As individuals gradually improve (principle of progression; see p. 80 of your textbook), the amount of resistance and the number of repetitions will typically change. More advanced exercisers and older teens will typically use greater resistance and fewer repetitions (see Fitness for Life [5th ed.] for high school students).

American College of Sports Medicine. (2006). ACSM's guidelines for exercise testing & prescription (7th ed.). Philadelphia: Lippincott Williams & Wilkins.

Corbin, C.B., and R. Lindsey. (2007). Fitness for life (updated 5th edition). Champaign, IL: Human Kinetics.

Faigenbaum, A.D. (2003). Youth resistance training. President's Council on Physical Fitness and Sports Research Digest 4(3): 1-8. Available at www.fitness.gov


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Q:In the Fitness for Life: Middle School, you sometimes use the word "exercise" and sometimes use "physical activity." Aren’t these two the same thing?

A:The terms "exercise" and "physical activity" have very similar meanings. However, experts now agree that "physical activity" is a term that has a much broader meaning than the word "exercise." Physical activity includes many types of activity, such as exercise, sports, dance, recreational activities, lifestyles activities, and many others. Exercise is one type of physical activity that is primarily used to build physical fitness. For example, muscle fitness exercises are referred to as "exercises" because they are designed especially to build muscle fitness. These and other exercises (such as flexibility exercises) are types of physical activity but are also considered to be exercise. Sports and dance are also types of physical activity but are not generally classified as exercise. Sports and dance could be done to get fit but are also frequently done for other reasons, such as having fun and being with friends. Some people do not understand the difference in terms, so it is not unusual to see the terms used interchangeably.


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Q:How often do experts suggest that teens do muscle fitness exercises?

A:The general recommendation for muscle fitness exercises for teens depends on several factors. First, it is important to know whether you want to build muscular endurance or muscular strength. Second, it is important to know your age. Finally, it is important to know if you are a beginner or a person who has been doing regular muscle fitness exercise. Strength exercises should be performed two to three days a week and not on consecutive days. For muscular endurance, the exercises can be done three to six days a week. For preteens (11-12), younger teens (13-14), and older teens who are just beginning, two days a week would be a good place to start. Preteens, younger teens, and beginners should do fewer sets and repetitions than older teens and those who have been doing regular muscle fitness exercises. Check table 7.2 on page 81 and the information on page 82 of the Fitness for Life: Middle School textbook for more information on how many sets and repetitions to perform.


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Q: Is the BMI (body mass index) a good indicator of body composition and body fatness?

A:The body mass index (BMI) uses a formula that includes height and weight. It is often used in research because it requires measurements that are easy to get (height and weight). Because it is easy to measure and does not require a lot of equipment, BMI can be easily assessed for large numbers of people. Still, the BMI has its limitations as a method of assessing body composition and/or body fatness. Both the BMI and height–weight charts have the problem of classifying some muscular people as overweight when they really are not. This is because people who have a lot of muscle can be high in weight without having too much body fat. This is a good reason for making many different assessments for body composition, including measurements such as skinfolds as shown on page 95 of your Fitness for Life: Middle School textbook. These measurements can give a truer indicator of "body fatness" than BMI. To review information on BMI and other measurements, refer to lesson 8.1 on pages 93 to 98 of the Fitness for Life: Middle School textbook.


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Q: What is the difference between "aerobic activity" and "active aerobic activity"?

A: "Aerobic activity" (as defined in your textbook) is any activity for which the body can supply enough oxygen to allow you to continue to be active for long periods of time. By this definition, walking, watching TV, playing computer games, and playing a musical instrument are aerobic activities because your body can supply enough oxygen to allow you to do them for a long time.

"Active aerobic activity" (as defined in your textbook) is an aerobic activity that is intense enough to elevate your heart rate into the aerobic target zone. Active aerobics are good for building cardiovascular fitness. Activities generally considered to be active aerobics can be done at a low intensity so that they fall below the aerobic target zone, in which case they would be aerobic but not active aerobics. For example, swimming slowly is an aerobic activity but is not an active aerobic activity. When swimming is performed vigorously enough to elevate the heart rate into the target zone, it is an active aerobic activity.


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Q: In the Physical Activity Pyramid on page 66, it says static stretching exercises should be held from 15 to 60 seconds, but on page 70 in table 6.2 it says stretches should be held for 15 to 30 seconds. Which is correct?

A:Actually, both answers (15-30 and 15-60) are correct. When you do stretching exercises (static), receptors in the muscle cause a "stretch reflex" that resists the muscle's attempts to stretch it. After a few seconds of stretching, the "stretch reflex" starts to diminish, allowing the muscle to lengthen. Much of the effect of the "stretch reflex" is gone after 15 seconds of stretching, but it takes 60 seconds for it to fully subside. This is why stretches should be at least 15 seconds. Most of the effect of the "stretch reflex" has gone away by 30 seconds, so many feel that 15 to 30 seconds is a good recommendation because you get most of the benefits of stretching and because the stretch is half as long as a 60-second stretch.

A 60-second stretch is better than a 30-second stretch, but some experts feel that many people will not adhere to a stretching exercise program if they have to do all stretches for 60 seconds. They reason that it is better to attempt 30-second stretches and really do them than to attempt 60-second stretches and fail to do them regularly.

We chose to list 15 to 60 seconds in the Pyramid because it is used in places other than this text and it is a good general recommendation. We chose to use the 15- to 30-second stretch length in the table on page 70 because 30 seconds gives most of the benefits for half the time commitment.

Note that this question and answer only applies to the first printing of the book. In the second and future reprints of this book, we updated this information to say "15 to 30 seconds" throughout for consistency.


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Q: I am on a sports team and do more than an hour of sports practice each day. Do I have to do lifestyle activity to meet the activity recommendation for teens?

A: As mentioned in chapter 1, teenagers should get 60 or more minutes of physical activity each day. Ideally, teens will select some activity from each of the activity categories in the first three levels of the physical activity pyramid. But if you do muscle fitness exercises, flexibility exercises, and vigorous activities that build cardiovascular fitness as part of a sport practice, you will meet the activity recommendation for teens. Activities at level 2 of the pyramid (including active sports) provide many of the same health benefits as those at level 1 (moderate lifestyle activities). The reason for recommending daily moderate (lifestyle) activity for teens is that this is the type of activity that is done most frequently by adults. If you develop a pattern of doing moderate activity early in life, you are more likely to be active as an adult, even when you are no longer playing on a sports team.


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Q: Is it possible to get too much practice?

A: As you learned in chapter 2, "good" practice is necessary for improving sport skills and other physical or motor skills. In some cases, practicing too long causes you to get tired. When you become too tired, you may practice incorrectly. You should practice some when you are fatigued so that you can learn to perform well and build your endurance. But when you practice too long and reinforce bad technique rather than good skills, you no longer benefit from the practice.


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Q: Why does the Fitness for Life: Middle School student textbook sometimes use FITT and other times use FIT?

A: As explained in chapter 3, the acronym FITT is used to help you remember the formula for how much physical activity you need to perform to build fitness and health.

Once you decide which type of activity you plan to do (such as moderate lifestyle activity, active aerobics, active sports and recreation, flexibility exercises, or muscle fitness exercises) you need only use FIT because the type of activity has already been determined (one of the five types listed in the previous sentence). FIT will help you determine the frequency, intensity, and time for the type of activity chosen.


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Q:How can I help my parents have better cardiovascular fitness?

A: Adults are often less active and less fit than teens. Adults are also nearly four times more likely to be overweight than teens. You can help your parents and other adults by discussing your concerns with them (that you know cardiovascular fitness is important for them too) and doing some of these things:

Research indicates that teens can influence their parents and other adults. When teens work together with adults, they are more active and eat better, which result in better fitness, lower body fat, and better health for all concerned.


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Q: If you want to play sports, is it better to specialize in one sport or learn to do several different sports?

A: That's a very good question, but it's also a hard one to answer. A lot depends on your personal goals and personal abilities. Because we’re most interested in the fitness, health, and wellness of teens, we encourage participation in a variety of activities from the Physical Activity Pyramid, not just one sport. Each of the five types of activities from the first three levels of the physical activity pyramid has different benefits, so performing a variety of activities will provide you with a variety of benefits in fitness, health, and wellness. Also, people who learn a variety of activities and perform them regularly as teens are more likely to be active and fit later in life. So if your goal is good fitness, health, and wellness both for now and later in life, we suggest learning many different activities.

It is true, however, that many successful athletes specialize in one sport. They think that by specializing they can spend more time practicing to become really skilled at one thing rather than divide practice time among several sports. So it can be argued that if your goal is to be really good at one sport, specialization can work. The problem with that approach is that many young adults do not continue to play a sport after they get out of school. So people who learn only one sport may be better at it when they are young, but they may not be active later in life because they can do only one sport well.


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Q:When is the best time to do stretching exercises to improve flexibility?

A:As you learned from reading the Fitness for Life: Middle School student textbook, the ability of your joints to move the way that they’re supposed to move is called flexibility. Long muscles and tendons allow you to have good flexibility. Stretching, using the types of static stretches and/or PNF stretches described in the text, is the best way to stretch muscles and tendons and improve flexibility.

The best time to do your stretching is when the muscles are warm. Many experts recommend that you do your stretching program after you have done a general warm-up or, even better, after you have been exercising for at least 10 minutes. Warm muscles stretch easier than cold muscles, so your program will be more effective if you do your stretching after doing other exercise.

The warm-up done prior to your exercise program is not the same thing as a stretching program or workout that you do as part of your total exercise program.

Sometimes, people do stretching exercises separately from other parts of their total exercise program. For example, they might stretch first thing in the morning or before going to bed at night. If you choose to do this, you should do a good general warm-up before stretching.


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Q: Can girls build big muscles if they do muscle fitness exercises?

A: Sometimes girls worry about doing exercises for muscle fitness because they are afraid that they will build big muscles. It is true that muscle fitness exercises cause muscles to get bigger for both boys and girls. But it is also true that most girls will not be able to build muscles as big as boys can. During the teen years and into adulthood, the body produces more of the hormone that causes the body to build muscle than it does during childhood. But males get much more of that hormone than females. That is why males develop bigger muscles than females do. Most experts, and most girls and women who have done regular exercise, agree that building muscles helps you look your best because muscles keep your abdomen from protruding and help you to look firm and fit. Muscle fitness provides many benefits other than feeling and looking your best (see chapter 7).


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Q: Is it possible to be physically fit and still have too much body fat?

A: Yes, it is possible to have too much body fat and still have good physical fitness. But before we more fully answer the question, we want to say that it is best to be fit and to have a healthy level of body fat. But you can have too much body fat and still be fit. As you learned earlier, there are many kinds of health-related physical fitness: body composition (also known as body fatness), cardiovascular fitness, flexibility, muscular endurance, and strength. All parts of fitness relate to each other, but each is also somewhat separate from all others.

So you can have good cardiovascular fitness and still have more body fat than you should have. Extra body fat will make it more difficult to score well on running tests of cardiovascular fitness because you have to carry more body weight during tests. You can be flexible and have a body fat level above the healthy fitness zone, but excess body fat can restrict range of motion in some joints. You can also be high in body fat and have good muscle fitness. Many sumo wrestlers are very overweight but can also be quite strong. Unfortunately, you can be quite strong (meaning you can lift a heavy weight) but have a hard time lifting your own body weight if you have excessive body fat.


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Q: Why do some kids who don't do a lot of exercise score better on fitness tests than some kids who exercise a lot?

A: It is true that sometimes people who do not do a lot of physical activity score better on fitness tests than others who are more active. That is more likely to be true when you are young than when you get older. The reasons some less active people can do well on fitness tests include heredity, maturation (age), and gender. Some people inherit physical characteristics from their parents that help them to do well on fitness tests. For example, there are different types of muscle fibers, and you may score well if you inherit the types of fibers that help you perform certain tests. The types of bones, joints, and body organs (such as the heart and lungs) that you inherit can affect your performance on fitness tests.

Also, some teens mature earlier than others. This means that they grow faster and their bodies produce hormones earlier than other teens do. People who mature early tend to do better on fitness tests than those who mature later. Teens in the same class who are older than others typically do better on fitness tests. As described in the book, males often do better than females in fitness activities that require muscle size.

As teens grow older, maturation and age become less of a factor because at some point all teens mature and get the fitness benefits of maturation. Also, heredity becomes less of a factor as you age. Among adults, healthy lifestyles are the main reason for good (or not so good) performance on fitness tests. For the reasons described here, we encourage you to focus on avoiding comparisons to others. Trying to reach the healthy fitness zone on all fitness tests is most important. We believe that self-comparisons over time are much more important than comparisons to other people.


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