目的 比较髋外展肌疲劳对不同性别人群单腿侧跳落地期间的姿势稳定性及其神经肌肉控制的影响。方法 比较20名男性和20名女性在髋外展肌疲劳干预前后进行单腿侧跳落地期间的压力中心(center of pressure, COP)、地面反作用力(ground reaction force, GRF)、下肢运动学、关节力矩、肌肉活动度等。结果 疲劳后男生和女生的COP在冠状面上的最大位移和位移速率增加。疲劳后髋关节外展峰值角度和踝关节外翻峰值角度增加。疲劳后踝关节内翻峰值力矩增加,男生踝关节跖屈峰值力矩大于女生。触地前200-ms,男生股直肌、股二头肌、胫前肌、腓骨长肌的激活小于女生；触地后200-ms,男生股二头肌激活小于女生,疲劳后男生胫前肌激活增加。结论 髋外展肌疲劳会导致冠状面姿势稳定性下降。踝关节冠状面控制减弱。女生比男生表现出更强的预期姿势控制。下肢关节损伤机制的性别差异值得进一步探究。
Objective To compare the effects of hip abductor fatigue on postural stability and its neuromuscular control group by sex during single-leg side-jump landing. Methods Twenty male and Twenty female adults were required to execute single-leg side-jump landing before and after hip abductor fatigue protocol. The center of pressure, ground reaction force, lower extremity kinematics, joint moment, muscle activity were compared. Results The max displacements and velocities of COP decreased after fatigue both in male and female. The peak angle of hip abduction and ankle eversion increased after fatigue. The peak torque of ankle inversion increased after fatigue. The peak torque of ankle plantar flexion was higher in male than in female. At the 200-ms pre-landing, the RMS of rectus femoris, biceps femoris, tibialis anterior, peroneus longus were lower in male than in female. At the 200-ms post-landing, the RMS of biceps femoris in male was lower than in female, and the RMS of TA increased in male after fatigue. Conclusions The postural stability in frontal plane decreased after hip abductor fatigue. The frontal plane control of ankle joint was weakened. Anticipatory postural adjustments strategy was stronger in female than in male. It was worth further exploring the sex difference in mechanism of lower extremity joint injuries.