Populations with lower extremity muscle weakness have difficulty performing the sit-to-stand (STS) transfer. The degree of weakness that can be tolerated before compromising the ability to perform this task is unknown. Using dynamic simulations, we investigated the effects of weakness before changes in kinematics/kinetics would be required. Lower extremity muscles were weakened globally and individually and muscle forces were re-estimated as the model tracked original task kinematics/kinetics. The STS transfer was sensitive to quadriceps and plantarflexor weakness, suggesting that strengthening these muscles or changing kinematics are essential for populations who have difficulty rising from a chair independently.

下肢肌肉无力的人群难以进行坐姿到站立姿势（STS）转移。在损害执行此任务的能力之前可以容忍的弱点程度未知。使用动态模拟，我们研究了需要改变运动学/运动学之前的虚弱影响。随着模型追踪原始任务运动学/运动学，下肢肌肉整体和个别减弱，并且重新估计了肌肉力量。STS转移对股四头肌和plant屈无力很敏感，这表明增强这些肌肉或改变运动学特性对于难以独立坐椅的人群至关重要。