Ito-Oonishi Sakiko, Takemura Masahiro, Kanamori Akihiro, Kusumoto Yasuaki, Miyakawa Shumpei
Department of Physical Therapy, School of Health Sciences, Tokyo University of Technology: 5-23-22 Nishikamata, Ota-ku, Tokyo 144-8535, Japan.
Faculty of Sport and Health Science, University of Tsukuba, Japan.
J Phys Ther Sci. 2021 Dec;33(12):908-911. doi: 10.1589/jpts.33.908. Epub 2021 Dec 1.
[Purpose] Understanding the neuromuscular cooperativeness functions when an athlete is fatigued is essential in preventing sports injuries and examining post-injury return standards. This study aimed to investigate the kinds of changes in neuromuscular cooperativeness before and after fatigue loading. [Participants and Methods] Fifteen female university athletes were examined for chronological changes in neuromuscular cooperativeness. Muscle fatigue loading was performed using BIODEX (180°/s) during knee flexion and extension exercises on one side. Surface electromyography of the rectus femoris and biceps femoris was performed on both sides before and immediately, 5 min, 10 min, and 15 min after loading. The switching silent period and pre-motor time were calculated from the electromyographic waveforms to indicate neuromuscular cooperativeness. [Results] The switching silent periods in the loading side immediately and 5 min after loading were significantly prolonged compared with that before loading. [Conclusion] Muscle fatigue loading instantaneously prolonged the switching silent period and decreased the neuromuscular cooperativeness. Furthermore, recovery generally occurred within 10 minutes after loading.
[目的]了解运动员疲劳时的神经肌肉协作功能对于预防运动损伤和检查伤后恢复标准至关重要。本研究旨在调查疲劳负荷前后神经肌肉协作的变化类型。[参与者与方法]对15名女大学生运动员的神经肌肉协作随时间的变化进行了检查。在一侧膝关节屈伸运动期间使用BIODEX（180°/秒）进行肌肉疲劳负荷。在负荷前、负荷后即刻、5分钟、10分钟和15分钟对双侧股直肌和股二头肌进行表面肌电图检查。从肌电图波形计算开关静息期和运动前时间以指示神经肌肉协作。[结果]负荷侧负荷后即刻和5分钟时的开关静息期与负荷前相比显著延长。[结论]肌肉疲劳负荷瞬间延长了开关静息期并降低了神经肌肉协作。此外，恢复通常在负荷后10分钟内发生。
