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arXiv · 1402.1713

Determination of subject-specific muscle fatigue rates under static fatiguing operations

Liang Ma·Wei Zhang·Bo Hu·Damien Chablat·Fouad Bennis·François Guillaume
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Abstract

Cumulative local muscle fatigue may lead to potential musculoskeletal disorder (MSD) risks {\color{red}, and subject-specific muscle fatigability needs to be considered to reduce potential MSD risks.} This study was conducted to determine local muscle fatigue rate at shoulder joint level based on an exponential function derived from a muscle fatigue model. Forty male subjects participated in a fatiguing operation under a static posture with a range of relative force levels (14% - 33%). Remaining maximum muscle strengths were measured after different fatiguing sessions. The time course of strength decline was fitted to the exponential function. Subject-specific fatigue rates of shoulder joint moment strength were determined. Good correspondence ($R^2>0.8$) was found in the regression of the majority (35 out of 40 subjects). Substantial inter-individual variability in fatigue rate was found and discussed.

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Liang Ma, Wei Zhang, Bo Hu, Damien Chablat, Fouad Bennis, François Guillaume. 2014-02-07. Determination of subject-specific muscle fatigue rates under static fatiguing operations. https://arxiv.org/abs/1402.1713

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