Coloretti Vittorio, Quagliarotti Claudio, Gatta Giorgio, Piacentini Maria Francesca, Cortesi Matteo, Fantozzi Silvia
Department for Life Quality Studies, University of Bologna, 40126 Bologna, Italy.
Department of Movement, Human and Health Sciences, University of Rome 'Foro Italico', 00135 Rome, Italy.
Sensors (Basel). 2025 Jul 3;25(13):4148. doi: 10.3390/s25134148.
Muscle activity during exercise is typically assessed using oximeters, to evaluate local oxygen saturation (SmO), or surface electromyography (sEMG), to analyze electrical activation. Despite the importance of combining these analyses, no study has evaluated both of them during specific swimming exercises in combination with mechanical power output. This study aimed to assess muscle activity during an incremental test on a swim-bench utilizing oximeters and sEMG. Nine male swimmers performed a five-steps test: (3 min at rest), 1, 2, and 3 (swimming at a frequency of 25, 30, and 40 cycle/min for a duration of 2, 2, and 1 min, respectively), and (5 min at rest). Each swimmer wore two oximeters and sEMG, one for each triceps brachii. Stroke frequency and arm mechanical power (from ~13 to ~52 watts) estimated by the swim-bench were different among all steps, while no differences between arms were found. SmO (from ~70% to ~60%) and sEMG signals (from ~20 to ~65% in signal amplitude) showed a significant increase among all steps. In both arms, a large/very large correlation was found between mechanical power and SmO (r < -0.634), mechanical power and sEMG onset/amplitude (r > 0.581), and SmO and sEMG amplitude (r > 0.508). No correlations were found between the slope of the sEMG spectral indexes and the slope of SmO; only sEMG detected electrical manifestation of muscle fatigue through the steps ( < 0.05). Increased muscle activity, assessed by both oximeters and sEMG, was found at mechanical power increases, revealing both devices can detect effort variation during exercise. However, only sEMG seems to detect peripheral manifestations of fatigue in dynamic conditions.
运动期间的肌肉活动通常使用血氧计进行评估，以评估局部氧饱和度（SmO），或使用表面肌电图（sEMG）来分析电激活情况。尽管将这些分析结合起来很重要，但尚无研究在特定游泳练习期间结合机械功率输出对两者进行评估。本研究旨在利用血氧计和sEMG评估在游泳训练台上进行递增测试期间的肌肉活动。九名男性游泳运动员进行了一个五步测试：（休息3分钟），步骤1、2和3（分别以25、30和40次/分钟的频率游泳2、2和1分钟），以及步骤4（休息5分钟）。每位游泳运动员佩戴两个血氧计和sEMG，分别用于每侧肱三头肌。游泳训练台估计的划水频率和手臂机械功率（从约13瓦至约52瓦）在所有步骤之间均不同，而两侧手臂之间未发现差异。SmO（从约70%至约60%）和sEMG信号（信号幅度从约20%至约65%）在所有步骤中均显著增加。在两侧手臂中，发现机械功率与SmO之间存在大/非常大的相关性（r < -0.634），机械功率与sEMG起始/幅度之间存在大/非常大的相关性（r > 0.581），以及SmO与sEMG幅度之间存在大/非常大的相关性（r > 0.508）。未发现sEMG频谱指数的斜率与SmO的斜率之间存在相关性；只有sEMG在各步骤中检测到了肌肉疲劳的电表现（P < 0.05）。在机械功率增加时，通过血氧计和sEMG评估均发现肌肉活动增加，这表明两种设备均可检测运动期间的用力变化。然而，似乎只有sEMG能在动态条件下检测到疲劳的外周表现。
