Cai Hejin, Zhang Guoxin, Wei Linjuan, Xu Jialiang, Yan Fei, Zhang Ming
Department of Biomedical Engineering, Faculty of Engineering, The Hong Kong Polytechnic University, Hong Kong, 999077, Hong Kong SAR, China.
Research Institute for Sports Science and Technology, The Hong Kong Polytechnic University, Hong Kong, 999077, Hong Kong SAR, China.
Sci Rep. 2025 Jul 24;15(1):26932. doi: 10.1038/s41598-025-10429-9.
Sarcopenia causes muscle loss and functional decline in older adults, yet the lower limb muscle activation patterns of sarcopenic patients during functional activities remain unclear. This study aims to investigate the differences in muscle activation between sarcopenic and healthy older adults during functional activities and to explore task-specific compensatory neuromuscular strategies. Eight sarcopenic patients and eight age-matched healthy older adults performed the standardized six-meter walk test (6MWT) and five times sit-to-stand test (5STS) with surface electromyography (EMG) used to record activity from eight muscles of the dominant leg. Sarcopenic individuals exhibited lower walking speed (p = 0.005) and shorter stride length (p < 0.001) in 6MWT, as well as longer completion time (p < 0.001) in 5STS. Significant differences in muscle activation (p < 0.05) included: increased proximal muscle activation with decreased distal activation in both tasks; elevated antagonist co-activation during critical movement transitions; and task-specific EMG variability patterns with increased EMG variability during walking but decreased variability during sit-to-stand activities. Sarcopenic individuals demonstrate distinct muscle activation patterns compared to normally aging individuals. Rehabilitation for sarcopenia may benefit from incorporating ankle-strengthening exercises, functional coordination training, and task-specific neuromuscular control strategies with traditional strength-focused approaches.
肌肉减少症会导致老年人肌肉流失和功能衰退，但肌肉减少症患者在功能活动期间下肢肌肉的激活模式仍不明确。本研究旨在调查肌肉减少症患者与健康老年人在功能活动期间肌肉激活的差异，并探索特定任务的代偿性神经肌肉策略。八名肌肉减少症患者和八名年龄匹配的健康老年人进行了标准化的六米步行测试（6MWT）和五次坐立试验（5STS），并使用表面肌电图（EMG）记录优势腿八块肌肉的活动。肌肉减少症患者在6MWT中表现出较低的步行速度（p = 0.005）和较短的步幅（p < 0.001），在5STS中完成时间较长（p < 0.001）。肌肉激活的显著差异（p < 0.05）包括：在两项任务中近端肌肉激活增加而远端激活减少；关键运动转换期间拮抗肌共同激活增加；以及特定任务的肌电图变异性模式，即步行期间肌电图变异性增加，而坐立活动期间变异性降低。与正常衰老个体相比，肌肉减少症患者表现出不同的肌肉激活模式。肌肉减少症的康复可能受益于将踝关节强化运动、功能协调训练以及特定任务的神经肌肉控制策略与传统的以力量为重点的方法相结合。
