OBJECTIVE: To examine the effects of 15 months of resistance training on bone mineral density (BMD) in female adolescents (aged 14 to 17 years). STUDY DESIGN: Participants were randomly assigned to either a training (n = 46) or control group (n = 21). BMD and body composition were measured by using dual-energy x-ray absorptiometry. Strength was assessed by means of one-repetition maximums for the leg press and bench press. The exercise group trained 30 to 45 minutes a day, 3 days per week, using 15 different resistance exercises. Control participants remained sedentary (< 2 hours of exercise per week). RESULTS: Leg strength increased significantly (40%) in the exercise group, but there were no changes in the control group. Femoral neck BMD increased significantly in the training group (1.035 to 1.073 g/cm2, p < 0.01) but not in the control group (1.034 to 1.048 g/cm2). No significant changes were seen in either group in lumbar spine BMD (1.113 to 1.142 g/cm2 and 1.158 to 1.190 g/cm2, respectively) or total body BMD (1.103 to 1.134 g/cm2 and 1.111 to 1.129 g/cm2, respectively). CONCLUSION: Resistance training is a potential method for increasing bone density in adolescents, although such a program would be best done as part of the school curriculum.

Full text (sometimes free) may be available at these link(s):      help

• DOI
• PubMed
• PDF locator
• publisher