Early Muscular Fitness Adaptations In Children In Response To Two Different Resistance Training Regimens

Abstract

While it is generally believed that there is a direct linear relationship between training intensity and the magnitude of strength change, limited data suggest that children may respond differently to resistance exercise. PURPOSE To compare early muscular fitness adaptations in children in response to low repetition maximum (LRM) and high repetition maximum (HRM) resistance training. METHODS 23 girls and 20 boys between the ages of 8.0 and 12.3 years (mean age 10.6 +/− 1.3 yr.) volunteered to participate in this study. In twice-weekly sessions of progressive resistance training for 8 weeks, children performed one set of 6 to 10 RM (n = 12) or one set of 15 to 20 RM (n = 19) on nine child-size exercise machines. Children in the control group (n = 12) did not resistance train. Maximum strength (1 RM) on the chest press, local muscular endurance (15 RM) on the the leg press, long jump, vertical jump, and v-sit flexibility were assessed at baseline and post-training. RESULTS The LRM and HRM groups made significantly greater gains in 1 RM strength (21% and 23%, respectively) as compared to control group gains (1%). Only the HRM group made significantly greater gains in 15 RM local muscular endurance (42%) and flexibility (15%) than that recorded in the control group (4% and −5%, respectively). CONCLUSIONS If children perform one set per exercise as part of an introductory strength training program, these findings favor the prescription of a higher RM training range. Future long-term studies are needed to explore the effects of periodized resistance training on youth. Supported by a grant from the American Council on Exercise