Functional motor redundancy enables humans to move with distinct muscle activation patterns while achieving a similar outcome. Since humans select similar strategies, there seems to be an optimal control. However, older adults move differently to young adults. The question is whether this is this due to an altered reinforcement scheme, altered sensory inputs, or due to alterations in the neuromusculoskeletal systems, so that it is no longer optimal or possible to execute the same movement strategies. The aim of this study was to analyse natural compensation strategies in the vital daily-life-task, sit-to-walk, in relation to neuromuscular capacity and movement objectives in younger (27.2 ± 4.6 years, N = 27, 14♀) and elderly (75.9 ± 6.3 years, N = 23, 12♀) adults. Aspects of the neuromuscular system that are prone to age-related decline and feasible to quantify were assessed (i.e. strength, nerve conductivity, fear of falling). Kinematics and muscle activity were recorded and joint kinetics were estimated using biomechanical models. Elderly men consistently used their arms when standing up. This strategy was not associated with a lack of or a reduction in strength, but with a reduction, but no lack of, ankle joint range of motion, and with increased fear of falling. The results show that humans preferentially maintain a minimum threshold of neuromuscular reserve to cope with uncertainties which results in compensation prior to coming up against physical limitations. Smaller base of support while standing up, a compensatory strategy with possibly greater risk of falls, was associated with muscular weakness, and longer nerve conduction latencies.

功能性运动冗余使人类能够以不同的肌肉激活模式移动，同时获得类似的结果。由于人类选择了类似的策略，因此似乎存在最优控制。然而，老年人的移动方式与年轻人不同。问题是这是由于强化方案的改变、感觉输入的改变，还是由于神经肌肉骨骼系统的改变，所以执行相同的运动策略不再是最佳的或可能的。本研究的目的是分析重要的日常生活任务（从坐到走）中的自然补偿策略与年轻人（27.2 ± 4.6 岁，N  = 27, 14♀）和老年人（75.9 ± 6.3 岁，N = 23, 12♀) 成年人。评估了容易与年龄相关的衰退和量化可行的神经肌肉系统方面（即力量、神经传导性、对跌倒的恐惧）。记录运动学和肌肉活动，并使用生物力学模型估计关节动力学。老年男性站立时始终使用手臂。该策略与缺乏或减少力量无关，但与减少但不缺乏踝关节活动范围以及增加对跌倒的恐惧有关。结果表明，人类优先维持神经肌肉储备的最低阈值以应对不确定性，从而在遇到身体限制之前进行补偿。站立时的支撑基础较小，一种可能有更大跌倒风险的补偿策略，