Jankaew Amornthep, Wang Po-Chun, Jan Yih-Kuen, Hwang Ing-Shiou, Lin Cheng-Feng
Department of Physical Therapy, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
Department of Computer Science and Information Engineering, College of Electrical Engineering and Computer Science, National Cheng Kung University, Tainan, Taiwan.
J Biomech. 2025 Jan;179:112475. doi: 10.1016/j.jbiomech.2024.112475. Epub 2024 Dec 9.
This study aimed to investigate the hamstring activation in athletes with hamstring strain injuries in vertical jump tasks using an EMG time-frequency analysis. Fifteen injured athletes and 15 matched controls were recruited. The EMG signals of the lateral hamstring (LH) and medial hamstring (MH) were assessed during countermovement, squat, and drop vertical jump tasks. Wavelet analysis was used to analyze the hamstring activation during takeoff, flight, and landing phases. The kinetics outcomes were also investigated. The results showed a significantly lower mean frequency of the LH and MH for all phases and jumps in the injured group compared to the control group (p < 0.05). The activation deficit led to a higher landing force (p = 0.028) and loading rate (p = 0.024) in the injured athletes. The hamstrings were recruited to a greater extent during the countermovement jump compared to the other two jumping tasks. In conclusion, athletes with prior hamstring strain displayed neuromuscular deficits, indicating neuronal alteration after the strain. The persistent activation deficits led to a degraded jump-landing performance. In addition, the hamstring recruitment differed in different jumping tasks. The findings suggest that neuromuscular training may be beneficial as part of the daily training drills of hamstring strains.
本研究旨在通过肌电图（EMG）时频分析，调查腘绳肌拉伤的运动员在垂直跳跃任务中的腘绳肌激活情况。招募了15名受伤运动员和15名匹配的对照组。在反向运动、深蹲和下落垂直跳跃任务期间，评估外侧腘绳肌（LH）和内侧腘绳肌（MH）的肌电图信号。采用小波分析来分析起跳、飞行和着陆阶段的腘绳肌激活情况。还研究了动力学结果。结果显示，与对照组相比，受伤组在所有阶段和跳跃中LH和MH的平均频率显著更低（p < 0.05）。激活不足导致受伤运动员的着陆力更高（p = 0.028）和负荷率更高（p = 0.024）。与其他两项跳跃任务相比，反向运动跳跃期间腘绳肌的募集程度更大。总之，既往有腘绳肌拉伤的运动员表现出神经肌肉功能缺陷，表明拉伤后神经元发生了改变。持续的激活不足导致跳跃着陆表现下降。此外，不同跳跃任务中腘绳肌的募集情况有所不同。研究结果表明，神经肌肉训练作为腘绳肌拉伤日常训练的一部分可能有益。
