Faculty of Health Care and Medical Sports, Department of Rehabilitation, Teikyo Heisei University, 4-1 Uruido Minami, Ichihara, Chiba, 290-0193, Japan.
Faculty of Health and Medical Science, Department of Health and Dietetics, Teikyo Heisei University, 2-51-4 HigashiIkebukuro, Toshima-ku, Tokyo, 170-8445, Japan.
Eur J Appl Physiol. 2023 Feb;123(2):271-282. doi: 10.1007/s00421-022-05074-3. Epub 2022 Oct 19.
Electromyostimulation (EMS) induces a short-term change in muscle metabolism, and EMS training induces long-term improvements of muscle atrophy and function. However, the effects of EMS training on intramuscular fat in older adults are still poorly known. The purpose of this study was to examine whether the intramuscular fat index and biochemical parameters change with EMS training of the quadriceps femoris muscles in older adults.
Nineteen non-obese older men and women performed EMS training of the quadriceps femoris for 12 weeks (3 times/week; single session for 30 min). The intramuscular fat content index was estimated by echo intensity of the vastus lateralis and rectus femoris muscles on ultrasonography, and muscle thickness was also measured. Muscle strength was assessed as the maximal voluntary contraction during isometric knee extension. Echo intensity, muscle thickness, and muscle strength were measured before and after EMS training. A rested/fasting blood samples were collected before and after EMS training for measuring plasma glucose, insulin, free fatty acid, triglyceride, and interleukin-6 concentrations. To examine the acute effect of a single-EMS session on biochemical parameters, blood samples were taken before and after the EMS session.
EMS training did not significantly change echo intensity in muscles, muscle thickness, muscle strength, or biochemical parameters. Regarding the acute effect on blood lipid concentrations, a single-EMS session increased free fatty acid and glucose concentrations.
EMS sessions had an acute effect of increasing free fatty acid and glucose concentrations, but EMS training intervention did not improve intramuscular fat content.
肌电刺激（EMS）会引起肌肉代谢的短期变化，EMS 训练会引起肌肉萎缩和功能的长期改善。然而，EMS 训练对老年人肌肉内脂肪的影响仍知之甚少。本研究旨在探讨 EMS 训练是否会改变老年人股四头肌的肌肉内脂肪指数和生化参数。
19 名非肥胖的老年男性和女性接受了为期 12 周的股四头肌 EMS 训练（每周 3 次；单次 30 分钟）。通过超声检查股外侧肌和股直肌的回声强度来估计肌肉内脂肪含量指数，并测量肌肉厚度。肌肉力量通过等长膝关节伸展的最大自主收缩来评估。在 EMS 训练前后测量回声强度、肌肉厚度和肌肉力量。在 EMS 训练前后采集空腹血样，用于测量血浆葡萄糖、胰岛素、游离脂肪酸、甘油三酯和白细胞介素-6 的浓度。为了检测单次 EMS 疗程对生化参数的急性影响，在 EMS 疗程前后采集血样。
EMS 训练并未显著改变肌肉的回声强度、肌肉厚度、肌肉力量或生化参数。关于单次 EMS 疗程对血脂浓度的急性影响，单次 EMS 疗程会增加游离脂肪酸和葡萄糖浓度。
EMS 疗程会产生急性增加游离脂肪酸和葡萄糖浓度的效果，但 EMS 训练干预并未改善肌肉内脂肪含量。
