Division of Rehabilitation, Department of Clinical Practice and Support, Hiroshima University Hospital, Hiroshima, Japan.
Faculty of Frontier Engineering, Institute of Science & Engineering, Kanazawa University, Kanazawa-shi, Japan.
Eur J Sport Sci. 2021 Oct;21(10):1414-1422. doi: 10.1080/17461391.2020.1838617. Epub 2020 Nov 10.
The aim of the present study was to clarify the effect of electrical muscle stimulation (EMS) on the spatial distribution pattern of electromyographic activity in healthy young adults using multi-channel surface electromyography (SEMG). A total of 32 men (age = 21-26 years) were randomly assigned to the intervention group (= 18) and control group (= 14). Participants in the intervention group performed EMS to stimulate the bilateral lower limb muscle for four weeks (20 min/3 days/week). The control group received no EMS intervention. To understand the effects of EMS, the following measurements were made at baseline and four weeks: knee extension torque, muscle mass, and spatial distribution of neuromuscular activation during a target torques [10%, 30%, 50%, and 70% of the maximal voluntary contraction (MVC)] using multi-channel SEMG. The knee extension torque was significantly increased in intervention group compared with control group ( < 0.0001). However, the muscle mass did not show a significant difference between pre and post intervention in each group. The muscle activation patterns of 50% and 70% MVC task showed significant enhancement between baseline and four weeks in the intervention group. Furthermore, a moderate correlation between Δ knee extension torque and Δ spatial distribution pattern of electromyographic activity of 50% and 70% MVC in the intervention group was observed. These results suggested EMS intervention induced different distribution of muscle activity at high-intensity muscle contraction compared with low-intensity muscle contraction.
本研究旨在通过多通道表面肌电图（sEMG）阐明电肌肉刺激（EMS）对健康年轻成年人肌电图活动空间分布模式的影响。共有 32 名男性（年龄 21-26 岁）被随机分配到干预组（=18）和对照组（=14）。干预组的参与者接受了为期四周（每周 3 天，每次 20 分钟）的双侧下肢肌肉 EMS 刺激。对照组未接受 EMS 干预。为了了解 EMS 的效果，在基线和四周时进行了以下测量：膝关节伸展扭矩、肌肉质量和在目标扭矩（最大自主收缩的 10%、30%、50%和 70%）下的神经肌肉激活的空间分布，使用多通道 sEMG。与对照组相比，干预组的膝关节伸展扭矩显著增加（<0.0001）。然而，每组在干预前后的肌肉质量均无显著差异。在干预组中，50%和 70%MVC 任务的肌肉激活模式在基线和四周之间显示出显著增强。此外，在干预组中观察到 Δ膝关节伸展扭矩与 50%和 70%MVC 的 Δ肌电图活动空间分布模式之间存在中度相关性。这些结果表明，与低强度肌肉收缩相比，EMS 干预在高强度肌肉收缩时引起了不同的肌肉活动分布。
