Brachioradialis EMG RMS 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.研究目标 本研究旨在对比佩戴与不佩戴被动式上身外骨骼（CarrySuitⓇ）完成10分钟负重任务时的竖脊肌（erector spinae）疲劳程度、上肢肌肉活动度、身体区域不适感与心率，并考量性别因素的影响。 研究背景 被动式外骨骼已商业化上市，可辅助负重或搬运作业。然而目前关于其在负重任务中对肌肉活动、疲劳、心率及不适感影响的相关研究证据较为匮乏，且现有结论尚不统一。 研究方法 招募30名受试者（16名女性、14名男性），分别在两个非连续天数内，佩戴与不佩戴外骨骼完成10分钟、负重15kg的搬运任务。任务过程中记录受试者的心率，以及竖脊肌、三角肌、肱二头肌与肱桡肌的肌肉活动度。此外，在任务前后分别开展等长收缩保持测试，采集竖脊肌肌电图（electromyography）数据，并完成不适感评分。 研究结果 未佩戴外骨骼时，受试者上肢肌肉活动度在搬运任务中呈上升或维持稳定状态，且男性与女性均出现较高的峰值激活；而佩戴外骨骼时，上肢肌肉活动度显著降低。此外，佩戴外骨骼时的下背部峰值激活、心率与不适感评分均低于未佩戴状态。在男性受试者中，未佩戴外骨骼时肌肉激活显著不对称，佩戴外骨骼后则更为对称。 研究结论 本次测试的被动式上身外骨骼可有效减轻男女受试者在负重搬运时的身体负荷，以及负重对上肢与下背部产生的影响。