Department of Health and Sports, Niigata University of Health and Welfare, 1398, Shimamicho, Kita-ku, Niigata, Japan.
General Education Core Curriculum Division, Seigakuin University, 1-1, Tosaki, Ageo, Saitama, Japan.
Sci Rep. 2022 Sep 6;12(1):14546. doi: 10.1038/s41598-022-18624-8.
This study aimed to investigate whether muscle synergy differs between swimmers with and without swimmer's shoulder in the butterfly technique. Muscle synergies, which can assess muscle coordination, were analyzed using surface electromyography. Twenty elite swimmers were included in this study (swimmer's shoulder: n = 8; control: n = 12). The motions involved in executing the butterfly technique were classified into the early pull-through, late pull-through, and recovery phases. Muscle synergy data analyzed using the nonnegative matrix factorization method were compared between the two groups.The swimming velocities were 1.66 ± 0.09 m・s and 1.69 ± 0.06 m・s for the control and swimmer's shoulder groups, respectively. Four muscle synergies in both groups were identified: synergy #1, which was involved in the early pull; synergy #2, involved in the late pull; synergy #3, involved in the early recovery; and synergy #4, involved in pre- and posthand entry. Compared to the control group, the swimmer's shoulder group had a small contribution from the pectoralis major (p = 0.032) and a high contribution from the rectus femoris during the early pull phase (p = 0.036). In the late pull phase, the contribution of the lower trapezius muscle in the swimmer's shoulder group was low (p = 0.033), while the contribution of the upper trapezius muscle in the pre- and postentry phases was high (p = 0.032). In the rehabilitation of athletes with swimmer's shoulder, it is therefore important to introduce targeted muscle rehabilitation in each phase.
本研究旨在探讨在蝶泳技术中，患有肩袖撞击症（swimmer's shoulder）的游泳运动员和无此病症的游泳运动员之间的肌肉协同作用是否存在差异。使用表面肌电图（surface electromyography）分析肌肉协同作用，以评估肌肉协调性。本研究纳入了 20 名精英游泳运动员（肩袖撞击症组：n=8；对照组：n=12）。将执行蝶泳技术的动作分为早期拉水、晚期拉水和恢复阶段。使用非负矩阵分解方法分析肌肉协同作用数据，并比较两组之间的差异。两组的游泳速度分别为 1.66±0.09 m・s 和 1.69±0.06 m・s。两组均识别出 4 种肌肉协同作用：协同作用#1 参与早期拉水；协同作用#2 参与晚期拉水；协同作用#3 参与早期恢复；协同作用#4 参与入水前和入水后。与对照组相比，肩袖撞击症组的胸大肌贡献较小（p=0.032），早期拉水阶段的股直肌贡献较大（p=0.036）。在晚期拉水阶段，肩袖撞击症组的下斜方肌贡献较低（p=0.033），而入水前和入水后阶段的上斜方肌贡献较高（p=0.032）。因此，在运动员的康复治疗中，重要的是在每个阶段引入有针对性的肌肉康复。
