One of the most notable effects of ageing is an accelerated decline of skeletal muscle mass and function, resulting in various undesirable outcomes such as falls, frailty, and all-cause mortality. The loss of muscle mass directly leads to functional deficits and can be explained by the combined effects of individual fibre atrophy and fibre loss. The gradual degradation of fibre atrophy is attributed to impaired muscle protein homeostasis, while muscle fibre loss is a result of denervation and motor unit (MU) remodelling. Neuromuscular electrical stimulation (NMES), a substitute for voluntary contractions, has been applied to reduce muscle mass and functional declines. However, the measurement of the effectiveness of NMES in terms of its mechanism of action on the peripheral motor nervous system and neuromuscular junction, and multiple molecular adaptations at the single fibre level is not well described. NMES mediates neuroplasticity and upregulates a number of neurotropic factors, manifested by increased axonal sprouting and newly formed neuromuscular junctions. Repeated involuntary contractions increase the activity levels of oxidative enzymes, increase fibre capillarisation and can influence fibre type conversion. Additionally, following NMES muscle protein synthesis is increased as well as functional capacity. This review will detail the neural, molecular, metabolic and functional adaptations to NMES in human and animal studies.

衰老最显着的影响之一是骨骼肌质量和功能的加速下降，导致各种不良后果，如跌倒、虚弱和全因死亡。肌肉质量的损失直接导致功能缺陷，可以用单个纤维萎缩和纤维损失的综合影响来解释。纤维萎缩的逐渐退化归因于肌肉蛋白质稳态受损，而肌肉纤维丢失是去神经支配和运动单元 (MU) 重塑的结果。神经肌肉电刺激 (NMES) 是自主收缩的替代品，已被用于减少肌肉质量和功能下降。然而，根据其对周围运动神经系统和神经肌肉接头的作用机制来衡量 NMES 的有效性，并且没有很好地描述单纤维水平的多分子适应性。NMES 介导神经可塑性并上调许多亲神经因子，表现为轴突萌发增加和新形成的神经肌肉接头。反复的无意识收缩会增加氧化酶的活性水平，增加纤维的毛细血管化，并会影响纤维类型的转换。此外，随着 NMES 肌肉蛋白质合成的增加以及功能能力的增加。本综述将详细介绍人类和动物研究中对 NMES 的神经、分子、代谢和功能适应性。反复的无意识收缩会增加氧化酶的活性水平，增加纤维的毛细血管化，并会影响纤维类型的转换。此外，随着 NMES 肌肉蛋白质合成的增加以及功能能力的增加。本综述将详细介绍人类和动物研究中对 NMES 的神经、分子、代谢和功能适应性。反复的无意识收缩会增加氧化酶的活性水平，增加纤维的毛细血管化，并会影响纤维类型的转换。此外，随着 NMES 肌肉蛋白质合成的增加以及功能能力的增加。本综述将详细介绍人类和动物研究中对 NMES 的神经、分子、代谢和功能适应性。