Neuromuscular and Lower Limb Biomechanical Differences Exist between Male and Female Elite Adolescent Soccer Players during an Unanticipated Run and Crosscut Maneuver

BACKGROUND: Noncontact anterior cruciate ligament injuries often occur during sports such as soccer and basketball in which cutting or landing maneuvers are frequently performed. These injuries are more common in female athletes, and identifying biomechanical or neuromuscular risk factors related to gender may help with the development of preventive training programs aimed at reducing anterior cruciate ligament injury. HYPOTHESIS: Lower limb biomechanical and/or neuromuscular differences between male and female soccer players will be identified during unanticipated running and cutting maneuvers. STUDY DESIGN: Descriptive laboratory study. METHODS: A complete 3-dimensional kinematic, kinetic, and electromyographic analysis of the lower limb for an unanticipated straight-run and crosscut maneuver was performed on 42 (male, 21; female, 21) elite adolescent soccer players. RESULTS: For both maneuvers, female players had greater lateral gastrocnemius activity, normalized to maximal voluntary isometric contractions, and demonstrated a mediolateral gastrocnemii imbalance that was not present in male players. Rectus femoris activity for both maneuvers and vastus medialis and lateralis activity for the straight run only were also greater in female than in male athletes. Other notable differences captured for the maneuvers included female players having reduced hamstring activity, a reduced hip flexion moment, a reduced hip flexion angle, and an increased ankle eversion angle throughout stance compared with male players. CONCLUSION: This is one of the first studies to identify gastrocnemii differences between genders as a possible anterior cruciate ligament injury risk factor. Additional biomechanical and neuromuscular differences were also identified as potential risk factors. CLINICAL RELEVANCE: These findings provide insight into the noncontact anterior cruciate ligament injury gender bias and may help improve preventive training programs.