The Physical Activity Pyramid for Kids (Source: Fitness for Life Elementary School, Human Kinetics, 2010, used by permission) has five steps. Each of the steps is designed to illustrate a type of physical activity that has health benefits.
The first four types of physical activity - moderate activity, vigorous aerobics, vigorous sports and recreation, and muscle fitness exercises - were discussed in previous articles in this column. Today the discussion focuses on flexibility exercises.
Flexibility is a health-related component of physical fitness that is defined as "the ability to move your joints through a full range of motion."
Factors such as inherited joint structure affect flexibility, but the principal factor that allows a person to have good range of motion is the length of muscles and tendons.
Regular stretching exercise can result in improved flexibility for youth when done properly, but factors such as gender, body build, and age also affect it.
In general girls are more flexible than boys and young people are more flexible than older people.
People with certain body builds may have advantages or disadvantages in taking flexibility tests, but height is not an important determinant of flexibility.
Having good flexibility has been shown to help in maintaining a healthy posture. Poor flexibility has been shown, in some studies, to be associated with back pain.
Even the casual observers can see that good flexibility is necessary for sports performances such as gymnastics, diving, and punting a football. Stretching exercises are used by physical therapists to rehabilitate people who have been injured or have muscle related diseases.
Before discussing the FIT formula for building flexibility among youth, it is important to make the distinction between exercises for building flexibility and warm-up exercises. They are not the same thing!
The warm-up is a set of exercises traditionally done before a performance or a competition. It often includes stretching (flexibility exercises) and is purported to reduce injury and enhance performance.
The best type of warm-up for youth will be discussed in a future column. This article is about performing exercise to improve flexibility.
The best way to build flexibility for youth - and adults for that matter - is to apply the FIT formula (based on American College of Sports Medicine guidelines) for Flexibility Exercises. The FIT formula works best when the muscles have been warmed by moderate to vigorous aerobic exercise. The formula is shown below is for static stretch (stretch and hold):
• Frequency - Two to three days a week, daily is recommended for athletes and other people who require extra flexibility.
• Intensity - Stretch muscles and tendons to a length longer than normal - to point of tension - but not pain.
• Time - Hold the stretch for 10 to 30 seconds for two or four repetitions.
For best results exercises for the arms and shoulders, trunk, back, hips and legs are recommended. For most youth a worthy goal is to maintain current levels of flexibility into adulthood.
For the very young, playing games and doing activities that involve a full range of motion is adequate. Stretching exercises that apply the FIT formula can be performed by older youth to help them build flexibility and learn about it and its benefits.
For those involved in sports that require exceptional flexibility, guidance in advanced forms of flexibility exercise is appropriate.
Modified forms of yoga are also appropriate. As with muscle fitness training, instruction and supervision by qualified teachers, coaches, and leaders is recommended.
There are many types of flexibility exercises other than static stretch described here. Additional information about flexibility can be found at www.fitnessforlife.org (search flexibility, PNF, ballistic stretch).
• Ahwatukee Foothills resident Dr. Charles B. "Chuck" Corbin is professor emeritus at Arizona State University, author of more than 90 books on fitness and activity, and was the first chair of the President's Council on Physical Fitness, Sports, and Nutrition Science Board. For more information on the National Physical Activity Guidelines for Americans, go to www.health.gov/paguidelines.