Biceps RMS EMG percentiles.

Objective
The goal of this study was to compare erector spinae muscle fatigue, upper limb muscle activity, body areas discomfort, and heart rate during a 10-min carrying task with and without a passive upper-body exoskeleton (CarrySuitⓇ) while considering sex influences.
Background
Passive exoskeletons are commercially available to assist lifting or carrying task. However, evidence of their impact on muscle activity, fatigue, heart rate and discomfort are scarce and/or do not concur during carrying tasks.
Method
Thirty participants (16 females and 14 male) performed a 10-min, 15kg load-carrying task with and without the exoskeleton in two non-consecutive days. Heart rate, and erector spinae, deltoid, biceps and brachioradialis muscle activity were recorded during the carrying tasks. In addition, erector spinae electromyography during an isometric hold test and discomfort ratings were measured before and after the task.
Results
While without the exoskeleton upper limb muscle activity increased or remained constant during the carrying task and showing high peak activation for both males and females, a significant activity reduction was observed with the exoskeleton. Low back peak activation, heart rate and discomfort were lower with than without the exoskeleton. In males muscle activation was significantly asymmetric without the exoskeleton and more symmetric with the exoskeleton.
Conclusion
The tested passive exoskeleton appears to alleviate the physical workload and impact of carrying heavy loads on the upper limbs and lower back for both males and females.

研究目的
本研究旨在对比佩戴与未佩戴被动上身外骨骼（passive upper-body exoskeleton，CarrySuitⓇ）开展10分钟负重任务时，受试者的竖脊肌（erector spinae）疲劳程度、上肢肌电活动、身体区域不适感与心率水平，并考量性别带来的影响。
研究背景
被动外骨骼已实现商业化应用，可辅助起重或负重作业。但现有研究中，关于其在负重任务中对肌电活动、肌肉疲劳、心率及身体不适感影响的相关证据较为匮乏，且各研究结论尚未达成一致。
研究方法
本研究共招募30名受试者（16名女性、14名男性），分别在两个非连续的实验日内，完成佩戴与未佩戴外骨骼的10分钟15kg负重任务。负重任务过程中，同步记录受试者的心率，以及竖脊肌、三角肌（deltoid）、肱二头肌（biceps）与肱桡肌（brachioradialis）的肌电活动。此外，在任务前后分别测量受试者在等长收缩测试（isometric hold test）中的竖脊肌肌电图信号，以及身体不适感评分。
研究结果
未佩戴外骨骼时，受试者的上肢肌电活动在负重任务中呈上升或维持稳定状态，且男女受试者均出现较高的峰值激活水平；而佩戴外骨骼时，上肢肌电活动则出现显著降低。此外，佩戴外骨骼时的腰背峰值激活水平、心率与不适感评分均低于未佩戴外骨骼的水平。进一步分析显示，男性受试者未佩戴外骨骼时的肌肉激活显著不对称，佩戴外骨骼后则更为对称。
研究结论
本次测试的被动上身外骨骼可有效减轻男女受试者在负重作业时的身体负荷，以及负重对上肢与腰背带来的不良影响。