Is resistance training appropriate for children?
A recent position statement by the National Strength and Conditioning Association (NSCA), based on an extensive review of the literature, provides answers to that question. Performed properly, with appropriate supervision, muscle fitness training has health and performance benefits for youth. In addition to building muscle, resistance training increases bone density. Also increasing muscle mass can increase resting calorie expenditure and is beneficial in maintaining a healthy body weight.
Like moderate and vigorous activities, there is a FIT formula for muscle fitness exercises. For youth the formula is different for beginners, intermediate and advanced exercisers. The frequency is two to three days a week with beginners starting at two days per week. The intensity (resistance) is based on a percentage of 1RM and ranges from 50 percent for beginners to 70-plus percent for advanced exercisers. The 1RM refers to one repetition maximum, or the amount of weight or resistance that can be moved in one repetition of an exercise. Special procedures should be used when determining 1RM for youth, especially for those who are just beginning. The time for exercises ranges from one set of 10-15 repetitions (reps) for beginners to two to three sets of fewer repetitions for more experienced exercisers.
It should be noted that prior to adolescence, when hormones stimulate muscle growth for both boys and girls, there are limits to the amount of hypertrophy (increase in muscle cell size) possible among youth. Preadolescents gain muscle fitness, but it is mostly due to increased ability to recruit muscle fibers and increased skill at performing exercises.
As a result, extensive training can be discouraging among preadolescents since exercise may not provide the gains in muscle size that youth expect. After adolescence both boys and girls can increase muscle mass with appropriate training, but gains are greater in boys than girls. Studies indicate that both boys and girls can enhance appearance and performance as a result of appropriate training.
While muscle fitness exercises are appropriate for youth, they do involve risks. Most injuries in muscle fitness exercises among youth occur when performing exercises incorrectly and when inappropriately competing or playing with weights rather than exercising correctly. Some guidelines for youth follow.
• Before beginning a program, instruction in proper exercise and spotting technique is critical.
• Before beginning an exercise program, testing of each muscle group using youth appropriate 1RM methods is essential. Exercise intensity should be based on 1RM for each exercise (for each muscle group).
• Exercises for each major muscle group should be performed.
• Instruction should come from a qualified teacher, coach or exercise leader, preferably one who has extensive education and certification as well as expertise in working with youth.
• Supervision is important. Youth should be encouraged to exercise in school programs or programs supervised by qualified instructors. Youth who exercise in gyms that feature strength development and bodybuilding for adults may be at risk of exposure to inappropriate advice and exposure to inappropriate substances and supplements.
More information about the NSCA position statement on Youth Resistance Training is available at www.nsca-lift.org/Publications/posstatements.shtml.
• 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.