A 10-week Neuromuscular Training Program Influences Hip and Knee Kinematics in Female Collegiate Soccer Players

Abstract

Anterior cruciate ligament (ACL) neuromuscular training programs have demonstrated beneficial effects in reducing ACL injuries, yet further evaluation of their effects on biomechanical measures across a sports team season is required to elucidate the specific factors that are modifiable. PURPOSE: The purpose of this study was to evaluate the effects of a 10-week off-season neuromuscular training program on lower extremity kinematics. METHODS: 12 Division I female soccer players (19.2±0.8 years, 1.67±0.1m, 60.2±6.5Kg) performed unanticipated dynamic trials of running-stop (RS) and sidestep cutting (SS) tasks pre- and post-training. The tasks were graphically projected in front of the subject through a custom-designed computer program and were performed in a randomized order for 5 trials each. Data collection was performed utilizing an 8-camera VICON system capturing at a rate of 270Hz. The 10-week training program consisted of resistance training two times per week and field training, consisting of plyometric, agility, and speed drills, two times per week. Paired samples t-tests were utilized to assess differences between pre- and post-training kinematics of the hip and knee at initial contact, peak knee flexion and maximal joint angle, with an alpha level set at.05. RESULTS: At initial contact, both tasks demonstrated a significant change from a knee abducted position (SS=-1.2±3.0, RS=-1.5±3.6) to a knee adducted position (SS=1.4±3.0, RS=1.5±3.9). The SS task demonstrated a mean change of 2.7±4.1°(t=-2.243, p=.046), and the RS demonstrated a mean change of 2.9±3.1°(t=-3.272, p=.007). There was a significant increase in hip abduction at initial contact for the SS task (3.2±4.2°; t=2.688, p=.021) and the RS task (4.3±4.5°; t=3.275, p=.007). For the SS task, the maximal knee abduction angle demonstrated a significant decrease of 4.5±6.3°(t=-2.495, p=.030). The hip abduction angle at peak knee flexion demonstrated a significant increase of 3.8±3.2°(t=4.110, p=.002). CONCLUSIONS: The neuromuscular training program demonstrated a positive effect in altering frontal plane mechanics that influence the risk of incurring an ACL injury. Future studies should assess the use of prevention programs in strength and conditioning sessions, as well as the longitudinal and retention effects of such an application.