Faculty of Bioscience and Applied Chemistry, Hosei University, Tokyo, Japan.
Faculty of Health Care and Medical Sports, Teikyo Heisei University, Chiba, Japan.
Scand J Med Sci Sports. 2020 Mar;30(3):462-471. doi: 10.1111/sms.13589. Epub 2019 Nov 26.
Eccentric contractions (ECCs) cause muscle damage. In addition, we showed that ECCs induce nerve dysfunction and damage with rats and human.
We aimed to evaluate motor nerve conduction velocity (MCV) for flexor pollicis brevis muscle (FPBM) after ECCs.
Twelve men (years, 19.8 ± 1.7 years; height, 172.4 ± 7.0 cm; weight, 64.0 ± 8.6 kg) performed maximal 100 ECCs on their FPBM of non-dominant hands with torque dynamometer. The dominant hands were control (CON). Maximal voluntary contraction (MVC), range of motion (ROM), DOMS, and MCV were assessed before, immediately post, and 1, 2, and 5 days after ECCs. MCV was calculated as the distance by stimulation divided by the latencies of the waveforms generated. Values were statistically analyzed by two-way ANOVA, and the significance level was set at P < .05.
Decreases in MVC immediately (-32.9%) to 5 days after ECCs were significantly greater (P < .05) than for the CON group. ROM showed a significant decrease immediately (-21.6%) after ECCs compared with before ECCs and CON group (P < .05). DOMS after ECCs increased at 1 and 2 days (5.0 cm) after ECCs compared with before ECCs and CON (P < .05). Also, MCV after ECCs delayed significantly from immediately (-36.4%), 1, 2, and 5 days after ECCs compared with CON (P < .05), while no significant change in M-wave amplitude was observed over time for both ECCs and CON.
The present study showed that ECCs of the FPBM cause a significant delay in MCV of median nerve.
离心收缩（ECC）会导致肌肉损伤。此外，我们已经证明 ECC 会导致大鼠和人类的神经功能障碍和损伤。
我们旨在评估 ECC 后拇短展肌（FPBM）的运动神经传导速度（MCV）。
12 名男性（年龄，19.8±1.7 岁；身高，172.4±7.0cm；体重，64.0±8.6kg）使用扭矩测力计在非优势手的 FPBM 上进行最大 100 次 ECC。优势手为对照（CON）。在 ECC 之前、之后立即以及 1、2 和 5 天后评估最大自主收缩（MVC）、运动范围（ROM）、DOMS 和 MCV。MCV 是通过刺激距离除以产生的波形潜伏期计算得出的。使用双向方差分析对数值进行统计学分析，显著性水平设置为 P<.05。
ECC 后立即（-32.9%）至 5 天后 MVC 的下降明显大于 CON 组（P<.05）。ECC 后 ROM 与 ECC 前和 CON 组相比立即（-21.6%）显著下降（P<.05）。ECC 后 1 和 2 天的 DOMS 比 ECC 前和 CON 增加（5.0cm）（P<.05）。此外，与 CON 相比，ECC 后 MCV 立即（-36.4%）、1、2 和 5 天后明显延迟（P<.05），而 ECC 和 CON 的 M 波幅度在整个时间内没有明显变化。
本研究表明，FPBM 的 ECC 会导致正中神经的 MCV 明显延迟。
