National physical activity guidelines for youth developed by the U.S. Department of Health and Human Services (USDHHS) recommend at least 60 minutes of physical activity each day. The five steps of the Physical Activity Pyramid (figure 5.2) help you understand the five kinds of physical activity, which build different parts of fitness and produce different health and wellness benefits (recall the principle of specificity). To meet the recommended 60 minutes of daily activity, you can choose from the different types of activity. For optimal benefits, you should perform activities from all parts of the pyramid each week. As you can see, activities at or near the bottom of the pyramid may need to be done more frequently or for a longer time than those near the top of the pyramid to get the same volume of activity.
Figure 5.2 The new Physical Activity Pyramid for Teens.
Source: C.B. Corbin
Moderate Physical Activity
Moderate physical activity is the first step in the Physical Activity Pyramid, and it should be performed daily or nearly every day. Moderate activity involves exercise equal in intensity to brisk walking. It includes some activities of normal daily living (also called lifestyle activities), such as yardwork (for example, raking leaves or mowing the lawn) and housework (for example, mopping the floor). It also includes sports that are not vigorous, such as bowling and golf. Some other sports can be either moderate or vigorous; for example, shooting basketballs is typically a moderate activity, whereas playing a full-court game is vigorous. National guidelines recommend 60 minutes of moderate to vigorous activity each day for teens. Moderate activity should account for some of this time each day (30 minutes a day is recommended for adults). It is also associated with many of the health benefits of activity described in this book, such as controlling your level of body fat, and is well suited for people of varying abilities.
Step 2 of the Physical Activity Pyramid represents vigorous aerobics, which includes any exercise that you can do for a long time without stopping and that is vigorous enough to increase your heart rate, make you breathe faster, and make you sweat. Thus these activities are more intense than moderate activities such as brisk walking. Vigorous aerobics, such as jogging and aerobic dance, are typically continuous in nature. Like moderate activity, they provide many health and wellness benefits, and they’re especially helpful for building a high level of cardiorespiratory endurance. You should perform vigorous aerobics (or vigorous sport or recreation) at least three days a week for at least 20 minutes each day in order to meet national activity guidelines.
Vigorous aerobic activity helps you build cardiorespiratory endurance.
Vigorous Sport and Recreation
Like vigorous aerobics, vigorous sport and recreation (represented in step 3 of the Physical Activity Pyramid) require your heart to beat faster than normal and cause you to breathe faster and sweat more. As your muscles use more oxygen, your heart beats faster, and you breathe faster and more deeply to meet the oxygen demand. Unlike vigorous aerobics, however, vigorous sport and recreation often involve short bursts of activity followed by short bursts of rest (as in basketball, football, soccer, and tennis). When done for at least 20 minutes a day in bouts of 10 minutes or more at a time, these activities provide similar fitness, health, and wellness benefits to those of vigorous aerobics. They also help you build motor skills and contribute to healthy weight management. As with vigorous aerobics, you can use vigorous sport and recreation to meet national activity recommendation when you do them for at least 20 minutes a day on three days a week.
Fitness Technology: Activitygram
You can use computer technology to keep track of your daily physical activity. Activitygram is a computer program that helps you track your physical activity over a three-day period. You enter any activity you perform for every 30-minute block of time during your waking hours. You also record the type of activity you do and whether its intensity level is resting, light, moderate, or vigorous. The program generates a report showing your total number of activity minutes each day, the amount of activity you did at each step of the Physical Activity Pyramid, and the amounts of moderate activity and vigorous activity you performed.
Reprinted by permission from Cooper Institute, 2003, Activitygram (Champaign, IL: Human Kinetics).
Locate the Activitygram portion of the student section of the Fitness for Life website. Open the document that explains Activitygram and use the information you find there to estimate the amount of activity you get from each of the different types shown in the pyramid. Ask your instructor for more information about Activitygram.
Muscle Fitness Exercises
Step 4 in the Physical Activity Pyramid represents muscle fitness exercises, which build your strength, muscular endurance, and power. Muscle fitness exercises include both resistance training (with weights or machines) and moving your own body weight (as in rock climbing, calisthenics, and jumping). This type of exercise produces general health and wellness benefits, as well as better performance, improved body appearance, a healthier back, better posture, and stronger bones. These exercises can be used to meet national activity guidelines and should be performed on two or three days a week.
Step 5 of the Physical Activity Pyramid represents flexibility exercises. According to ACSM, flexibility exercises improve postural stability and balance. There is also some evidence that flexibility exercises may reduce soreness, prevent injuries, and reduce risk of back pain. Flexibility exercises also improve your performance in activities such as gymnastics and dance. They also are used in therapy to help people who have been injured. Two examples of flexibility exercise are stretching and yoga (figure 5.3). To build and maintain flexibility, you should perform flexibility exercise at least three days a week.
Figure 5.3 Yoga is one type of physical activity for improving flexibility.
Just below the Physical Activity Pyramid (see figure 5.2) you’ll notice pictures of a television set and a video game controller with an X over them. This illustration emphasizes the fact that being sedentary, or inactive, poses a health risk.
Just as you should do 60 minutes of physical activity each day, drawing from the five types of activity presented in the pyramid, you should also avoid the inactivity that is common among people who log too much "screen time" on a daily basis. Screen time refers to time spent in front of a TV, computer game, phone screen, or any other device that substitutes inactivity for activities from the pyramid. A recent survey of children and teens in the United States found that they watch TV for an average of nearly four hours a day! Sixty-eight percent of teens have a TV in their room, and of course many also spend screen time on computers, video games, movies, and cell phones, more than doubling the amount of time they spend watching a screen. Research shows that screen time results in inactivity and increases health risk.
We all need to take time to recover from daily stresses and prepare for new challenges, so periods of rest and sleep are important for good health. Some activities of daily living - such as studying, reading, and even a moderate amount of screen time - are appropriate. But general inactivity or sedentary living is harmful to your health. Your choices from active areas of the pyramid should exceed your choices from the inactivity area.
The top of the pyramid presents a balance scale illustrating the need to balance the energy you take in (food) with the energy you put out (activity). Energy balance means that the calories in the food you eat each day are equal to the calories you expend in exercise each day. Balancing your energy in this way is essential to maintaining a healthy body composition.