Sex differences in kinematics and muscle activity during the impact phase of a single-leg landing task after a backhand side overhead stroke in badminton

Abstract Our study aimed to investigate possible risk factors for the high incidence of ACL injuries in women compared to men during the impact phase of badminton single-leg landing maneuvers. Sixteen badminton players (8 male, 8 female) participated in a badminton single-leg landing task in which lower limb kinematics, ground reaction forces, and lower limb muscle activity were measured using a marker-based motion capture system, force plates, and electromyography (EMG). An analysis of variance (ANOVA) was used to analyze gender differences in leg kinematic data, mean normalized leg muscle activation (MVC%), and muscle co-contraction during the impact phase after landing. During the impact phase of the badminton landing task (100 ms after initial contact), the knee valgus angle at the moment of initial contact （IC）and posterior peak ground reaction force（GRF） was greater in females than in males. Knee flexion angle and ankle plantarflexion angle were less in females than in males at the moment of peak posterior GRF. During the post-landing impact phase, compared to male badminton players, females exhibited greater rectus femoris medial hamstring, medial gastrocnemius, and lateral gastrocnemius muscle activity. In addition, males exhibited a higher co-contraction ratio of the medial and lateral gastrocnemius than female athletes. The neuromuscular control strategies exhibited by female badminton players may be inadequate for ACL protection and may be a potential risk factor for a high incidence of ACL injury.