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Published on: February 22, 2022
Lower Music Volume Levels in Fitness Class and Perceived Exercise Intensity
Kaitlin Hori1, Choo Phei Wee2, Nicholas Liu1
1Keck School of Medicine, University of Southern California, Los Angeles.
Importance:
Loud music in group fitness classes is often believed to enhance motivation and performance but poses a risk for noise-induced hearing loss.
Objective:
To assess whether lower music volume during fitness classes results in comparable perceived exertion compared with higher music levels and to explore hearing protection behaviors among participants.
Design, Setting, And Participants:
This comparative effectiveness study using a partially repeated measures design surveyed group fitness class attendees from February 1 to 28, 2025, at a fitness studio in Los Angeles, California, regarding perceived exercise intensity, music loudness, and hearing protection behaviors.
Exposures:
Participants attended 1-hour group fitness classes under typical (louder) and reduced music volume conditions (≥3-dBA reduction).
Main Outcomes And Measures:
Perceived exertion was compared between louder and quieter class conditions using multivariable mixed-effects linear regression to account for repeated measurements from participants. A noninferiority framework was applied, with noninferiority defined as the lower bound of the 97.5% CI.
Results:
A total of 189 participants completed 239 surveys, and 21 participants contributed surveys in both sound conditions. The median (range) age was 28 (17-59) years, and 165 (87.3%) were female. The mean sound levels were 91.4 dBA (95% CI, 91.1-91.9 dBA) for louder classes (n = 122) and 88.5 dBA (95% CI, 88.0-88.9 dBA) for quieter classes (n = 117). The lower bound of the 97.5% CI for the difference in perceived exertion (Borg CR-10) between louder and quieter classes (β = -0.66; 97.5% CI, -1.09 to -0.22) did not exceed the CI for the noninferiority threshold of -1.5, indicating noninferiority in perceived exertion in quieter classes compared to louder classes. Continuous unit-based modeling of sound intensity confirmed noninferiority for decrements up to 4 dBA. Twenty-eight individuals (14.8%) reported ever experiencing postclass tinnitus, and 4 participants (2.1%) reported consistently using hearing protection during classes.
Conclusions And Relevance:
In this comparative effectiveness study, reducing music volume in group fitness classes did not lead to meaningful reductions in perceived exertion and may reduce the risk of noise-induced hearing loss. These findings support implementing safer sound practices in fitness environments and underscore the need for increased awareness and education on hearing protection.
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