The Effect of Strength Training on the Jump-Landing Biomechanics of Young Female Athletes

OBJECTIVE: To investigate the effect of leg-focused strength training on the jump-landing mechanics of young female athletes. DESIGN: Single-blind, randomized controlled clinical trial. SETTING: University-based training program. PARTICIPANTS: Forty female athletes, 10 to 14 years old, were randomly allocated to intervention or active control. INTERVENTIONS: Twice weekly training was performed by the leg strengthening group [intervention group (IG); n = 19] and the active control group (CG; n = 17), for 12 weeks. Control group participants performed upper body strengthening exercises. MAIN OUTCOME MEASURE: Jump-landing performance was assessed by a blinded observer using the Landing Error Scoring System (LESS). RESULTS: There was no difference between the IG and CG postintervention (IG mean LESS score 6.0 ± SD 1.8 vs CG mean 6.1 ± SD 1.8; P = 0.85). CONCLUSIONS: Strength training of the legs does not seem to improve jump-landing abilities in young female athletes compared with active controls who strength-trained their arms. CLINICAL RELEVANCE: Leg strengthening may not provide an advantage over arm strengthening for improving jump-landing movement patterns in young female athletes. This has implications for the design of conditioning programs if injury prevention is a goal.