The influence of in-season injury prevention training on lower-extremity kinematics during landing in female soccer players

Objective: To examine the influence of in-season injury prevention training on hip and knee kinematics during a landing task. Design: Longitudinal pre-post intervention study. Setting: Testing sessions were conducted in a biomechanics research laboratory. Participants: Eighteen female soccer players between the ages of 14 and 17 participated in this study. All subjects were healthy with no current complaints of lower extremity injury. Interventions: Testing sessions were conducted prior to and following a season of soccer practice combined with injury prevention training. Main Outcome Measurements: During each testing session three-dimensional kinematics were collected while each subject performed a drop landing task. Peak hip and knee joint angles were measured during the early deceleration phase of landing and compared between pre- and post-training using paired t-tests. Results: Following a season of soccer practice combined with injury prevention training, females demonstrated significantly less hip internal rotation (7.1 degrees vs. 1.9 degrees; P = 0.01) and significantly greater hip abduction (-4.9 degrees vs. -7.7 degrees; P = 0.02). No differences in knee valgus or knee flexion angles were found post-season. Conclusions: Female soccer players exhibited significant changes in hip kinematics during a landing task following in-season injury prevention training. Our results support the premise that a season of soccer practice combined with injury prevention training is effective in altering lower extremity motions that may play a role in predisposing females to ACL injury.