Demolition hammering tasks are physically demanding tasks that could cause muscle fatigue and musculoskeletal disorders. Electromyography (EMG) data have been adopted to assess levels of muscular activity and onset of muscular fatigue for both industrial tasks and physical activities. An experiment simulating a manual demolition task on the ground was performed on 23 healthy male participants. The objectives were to test the hypotheses that the handle height and the force applied to affect the EMG amplitude, the increase of the EMG amplitude, and the decline of the mean power frequency (MPF) of the EMG for performing the tasks. This study also aimed at finding the most fatigued muscles which dominate the end of the sustained push‐down tasks in ground demolitions. The results showed that the EMG amplitude required to perform the tasks was significantly affected by the handle height and force applied. Significant increases in EMG amplitude and decreases in MPF were found. Bicep brachii, tricep brachii, and pectoralis major muscles were the most fatigued muscles that dominated the termination of the tasks. Pushing with body leaning forward to utilize partial body weight was less fatiguing than the other two postures. Elbow flexion is undesirable and should be avoided when performing such tasks.

中文翻译：

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地面拆除中的下推任务的肌肉疲劳测量

拆除锤击任务是对身体的苛刻任务，可能导致肌肉疲劳和肌肉骨骼疾病。肌电图（EMG）数据已用于评估工业活动和体育活动的肌肉活动水平和肌肉疲劳发作。对23名健康男性参与者进行了模拟地面上手动拆除任务的实验。目的是检验以下假设：手柄高度和施加的影响EMG振幅的力，EMG振幅的增加以及执行任务的EMG的平均功率频率（MPF）的下降。这项研究还旨在找到最疲倦的肌肉，这些肌肉主导着地面拆除中持续下推任务的结束。结果表明，执行任务所需的EMG幅度受手柄高度和所施加力的影响很大。发现肌电图振幅显着增加，MPF下降。肱二头肌，肱三头肌和胸大肌是最疲劳的肌肉，主导着任务的终止。身体向前倾以利用部分体重的推力比其他两种姿势的疲劳感小。肘部屈曲是不希望的，在执行此类任务时应避免。身体向前倾以利用部分体重的推力比其他两种姿势的疲劳感小。肘部屈曲是不希望的，在执行此类任务时应避免。身体向前倾以利用部分体重的推力比其他两种姿势的疲劳感小。肘部屈曲是不希望的，在执行此类任务时应避免。