NEW YORK, Jul 07 (Reuters Health) -- Weightlifting programs can improve the muscle tone and endurance in children -- and help them to feel good about their athletic performance, researchers conclude.
They recommend that resistance training programs for children include a high number of repetitions lifting moderate weights rather than few lifts of heavy weights, noting that high-repetition, moderate-weight training "resulted in more favorable changes in upper body strength."
In their study, Dr. Avery Faigenbaum and colleagues at the University of Massachusetts, in Boston the Boston researchers assigned 11 girls and 32 boys between 5 and 12 years of age to 8 weeks of weight training. Half of the children engaged in workouts consisting of 6 to 8 repetitions of each exercise, using relatively heavy weights. The other half of participants completed an average 13 to 15 'reps,' but with lighter loads.
In their report, published this month in the electronic version of the journal Pediatrics (www.pediatrics.org), the authors conclude that weight-training programs "can enhance the muscular strength and muscular endurance of children."
They also note that there were differences in outcome depending on the training regimen used. While leg muscle endurance improved in both exercise groups, children using high-rep, moderate weights experienced "significantly greater" gains in muscle endurance compared with children in the low-rep, high-weight group.
And while leg muscle strength increased by 31% in children engaged in low-rep, high-weight workouts, the benefit was even greater-- nearly 41% --in children involved in high-rep, moderate-weight workouts.
Most of the children appeared to show the greatest improvements in strength during the first 4 weeks of the program, with lower body muscles tending to be more responsive to weight training than muscles in the upper body.
The Boston team conclude that children should begin weight-training using moderate weights and a single set of 13 to 15 repetitions per exercise. This type of program "not only allows for positive changes in muscular performance," they explain, "but provides an opportunity for each child to experience success and feel good about his/her performance."
The researchers note that three major organizations -- the American Academy of Pediatrics, the American College of Sports Medicine, and the National Strength and Conditioning Association -- support children's participation in "appropriately designed and competently supervised" weight training programs.
SOURCE: Pediatrics 1999;104/1/e5.
