THE EFFECTS OF HEADING MOTION AND GENDER ON LOWER EXTREMITY BIOMECHANICS IN SOCCER PLAYERS

Soccer continues to experience growth internationally in both men and women. Thus, it’s reasonable to predict a high rate of injuries amongst those athletes since soccer includes strong physical contact. ACL injury is one of the most common injuries among athletes, and (70-84%) of ACL injuries occurs in non-contact situations, which often are associated with landing, deceleration, and sudden change of movement direction, and these situations might end with knee valgus collapse which’s a common mechanism of ACL injury. Further, there are biomechanical differences of lower extremity joints in various tasks with both genders, which apparently means that the task utilized plays a crucial influence on joints dynamics. In soccer, the heading motion is one of the most common activities, which is more likely associated with landing. The purpose of this study was to investigate the effect of forward heading motion by comparing the kinetics and kinematics of lower extremity between genders during 1) a stop-jump task and 2) a jump-heading task. 10 male and 10 female soccer players performed 5 stop-jumps and 5 jumps with heading a soccer ball. Findings displayed a combination of reduced initial knee flexion, greater initial hip flexion, greater peak vertical GRF, and greater peak knee extension moments with both genders during the jump-heading task. Additionally, greater peak knee abduction angles were observed among female players during both tasks. These findings suggest that a higher risk of non-contact ACL injuries might occur during the jump-heading task compared with the stop-jump task, and this risk could be higher among female players than male players. These findings might lead soccer trainers to consider different strategies and techniques of landing after heading motions in game-like conditions. Also, PTs and rehabilitation designers who work with ACL-injured patients might consider the outcome of this study. Future studies should consider to examine ankle dynamics in addition to knee and hip in game-like conditions.