Research Center of Exercise Capacity Assessment and Promotion, School of Sports Science and Physical Education, Northeast Normal University, Changchun, Jilin Province, China.
Research Field of Medical Instruments and Bioinformation Processing, College of Instrumentation & Electrical Engineering, Jilin University, Changchun, Jilin Province, China.
Exp Brain Res. 2024 Oct;242(10):2391-2404. doi: 10.1007/s00221-024-06909-5. Epub 2024 Aug 13.
This study aimed to utilize the nonnegative matrix factorization (NNMF) algorithm for muscle synergy analysis, extracting synergy structures and muscle weightings and mining biomarkers reflecting changes in muscle fatigue from these synergy structures. A leg press exercise to induce fatigue was performed by 11 participants. Surface electromyography (sEMG) data from seven muscles, electrocardiography (ECG) data, Borg CR-10 scale scores, and the z-axis acceleration of the weight block were simultaneously collected. Three indices were derived from the synergy structures: activation phase difference, coactivation area, and coactivation time. The indicators were further validated for single-leg landing. Differences in heart rate (HR) and heart rate variability (HRV) were observed across different fatigue levels, with varying degrees of disparity. The median frequency (MDF) exhibited a consistent decline in the primary working muscle groups. Significant differences were noted in activation phase difference, coactivation area, and coactivation time before and after fatigue onset. Moreover, a significant correlation was found between the activation phase difference and the coactivation area with fatigue intensity. The further application of single-leg landing demonstrated the effectiveness of the coactivation area. These indices can serve as biomarkers reflecting simultaneous alterations in the central nervous system and muscle activity post-exertion.
本研究旨在利用非负矩阵分解（NNMF）算法进行肌肉协同分析，提取协同结构和肌肉权重，并从这些协同结构中挖掘反映肌肉疲劳变化的生物标志物。通过 11 名参与者进行腿部按压运动以诱导疲劳。同时采集了七个肌肉的表面肌电图（sEMG）数据、心电图（ECG）数据、Borg CR-10 量表评分和重量块的 z 轴加速度。从协同结构中得出了三个指标：激活相位差、共激活面积和共激活时间。这些指标进一步在单腿着陆中得到验证。不同疲劳水平下观察到心率（HR）和心率变异性（HRV）的差异，差异程度不同。主要工作肌群的中值频率（MDF）表现出一致的下降。疲劳发作前后，激活相位差、共激活面积和共激活时间均存在显著差异。此外，激活相位差与共激活面积与疲劳强度之间存在显著相关性。单腿着陆的进一步应用证明了共激活面积的有效性。这些指标可以作为反映中枢神经系统和肌肉活动在运动后同时变化的生物标志物。
