Department of Industrial Management Engineering, Hanyang University, Ansan 15588, Korea.
Int J Environ Res Public Health. 2018 Apr 18;15(4):784. doi: 10.3390/ijerph15040784.
This research study aims at addressing the paradigm of whole body fatigue and local muscle fatigue detection for squat lifting. For this purpose, a comparison was made between perceived exertion with the heart rate and normalized mean power frequency (NMPF) of eight major muscles. The sample consisted of 25 healthy males (age: 30 ± 2.2 years). Borg’s CR-10 scale was used for perceived exertion for two segments of the body (lower and upper) and the whole body. The lower extremity of the body was observed to be dominant compared to the upper and whole body in perceived response. First mode of principal component analysis (PCA) was obtained through the covariance matrix for the eight muscles for 25 subjects for NMPF of eight muscles. The diagonal entries in the covariance matrix were observed for each muscle. The muscle with the highest absolute magnitude was observed across all the 25 subjects. The medial deltoid and the rectus femoris muscles were observed to have the highest frequency for each PCA across 25 subjects. The rectus femoris, having the highest counts in all subjects, validated that the lower extremity dominates the sense of whole body fatigue during squat lifting. The findings revealed that it is significant to take into account the relation between perceived and measured effort that can help prevent musculoskeletal disorders in repetitive occupational tasks.
本研究旨在探讨深蹲举重时全身疲劳和局部肌肉疲劳检测的范式。为此，我们比较了主观用力感觉与心率和 8 块主要肌肉的归一化均方根频率（NMPF）之间的关系。研究对象为 25 名健康男性（年龄：30±2.2 岁）。采用 Borg 的 CR-10 量表对身体的两个部位（下半身和上半身）和全身的主观用力感觉进行了评估。与上半身和全身相比，下半身在主观反应中更为明显。对 25 名受试者的 8 块肌肉的 NMPF 进行了协方差矩阵的主成分分析（PCA）。观察协方差矩阵中各肌肉的对角元素。观察到所有 25 名受试者中绝对值最大的肌肉。在 25 名受试者中，观察到三角肌和股直肌的 PCA 频率最高。股直肌在所有受试者中计数最高，这验证了在深蹲举重过程中，下半身主导着全身疲劳的感觉。研究结果表明，考虑到主观用力感觉和测量用力之间的关系是很重要的，这有助于预防重复性职业任务中的肌肉骨骼疾病。
