This study quantified sex-specific biomechanical adaptations to fatigue in asymmetric lifting. Twenty-one females and fifteen males performed a prolonged asymmetric lifting protocol while upper body, trunk and pelvis kinematics were collected. Features of movement identified with principal component analysis, and peak joint angular velocities and moments were calculated. Sex-specific kinematic adaptations to fatigue included females adopting a ‘stoop-like’ lifting strategy to a greater extent than males. Additionally, females exhibited higher vertical elbow positions during load rotation, moved their body toward the destination for load deposit, and did not reduce peak right shoulder flexion velocities, in contrast to male participants. Females also had greater low back and shoulder peak normalized joint moments. When fatigued, females adopted an asymmetric lifting strategy that minimized metabolic demand as supported by smaller decreases in maximum voluntary contractions. However, females' fatigue-related adaptations increased biomechanical exposures associated with injury risk.

这项研究量化了性别特异性生物力学对不对称举重疲劳的适应。二十一名女性和十五名男性执行了长时间的不对称提升方案，同时收集了上半身、躯干和骨盆的运动学数据。通过主成分分析确定运动特征，并计算峰值关节角速度和力矩。性别特异性对疲劳的运动适应包括女性比男性更大程度地采用“弯腰”举重策略。此外，与男性参与者相比，女性在负载旋转期间表现出更高的垂直肘部位置，将身体移向负载沉积的目的地，并且没有降低右肩弯曲峰值速度。女性的腰部和肩部峰值标准化关节力矩也更大。当疲劳时，女性会采取不对称举重策略，通过最大自主收缩较小的下降来最大限度地减少代谢需求。然而，女性与疲劳相关的适应增加了与受伤风险相关的生物力学暴露。