Validity of using perceived exertion to assess muscle fatigue during resistance exercises

Hanye Zhao; Takuya Nishioka; Junichi Okada

doi:10.7717/peerj.13019

Validity of using perceived exertion to assess muscle fatigue during resistance exercises

PeerJ. 2022 Mar 1:10:e13019. doi: 10.7717/peerj.13019. eCollection 2022.

Authors

Hanye Zhao¹, Takuya Nishioka¹, Junichi Okada²

Affiliations

¹ Graduate School of Sport Sciences, Waseda University, Tokorozawa, Saitama, Japan.
² Faculty of Sport Sciences, Waseda University, Tokorozawa, Saitama, Japan.

Abstract

Background: The rating of perceived exertion (RPE) is correlated with physiological variables. The purpose of this study was to assess the validity of using the Borg CR-10 scale and velocity to predict muscle fatigue assessed by surface electromyography during single joint resistance exercises.

Methods: Fifteen healthy males underwent different fatigue levels of unilateral elbow flexion (EF) and knee extension (KE), consisting of low, medium, and high volumes at 65% of their one-repetition maximum. The RPEs, spectral fatigue index (SFI), and mean velocity of the experimental exercises were assessed throughout the trials.

Results: Significant differences in overall RPE (p < 0.001) and average SFI (p < 0.001) were observed between the conditions in both exercises. Significant changes in RPE and SFI (p < 0.001) were observed throughout the EF, whereas a SFI increase (p < 0.001) was only observed at the end point of KE. Multiple regression analyses revealed two significant models (p < 0.001) for the prediction of muscle fatigue during EF (R² = 0.552) and KE (R² = 0.377).

Conclusions: Muscle fatigue resulted in similar increases in perceptual responses, demonstrating that RPE is useful for assessing fatigue when resistance exercise is performed. However, velocity changes may not reflect muscle fatigue correctly when exercise is no longer performed in an explosive manner. We recommend combining RPE responses with velocity changes to comprehensively assess muscle fatigue during clinical and sports situations.

Keywords: Borg scale; Muscle fatigue; Perceived exertion; Resistance training; Surface electromyography.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Exercise
Humans
Male
Muscle Fatigue*
Physical Exertion / physiology
Resistance Training* / methods
Weight Lifting / physiology

Grants and funding

This study was supported by JSPS KAKENHI Grant Number JP (19K11452). The first author is subsidized by China Scholarship Council under Grant Number (201908050185). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.