While a gym-based body composition challenge temporarily increased class attendance for all participants, these increases were generally not sustained after the challenge, though declines were attenuated by higher enjoyment motives.
Key Findings
Results
Class attendance generally increased for all participants during the 8-week body composition challenge.
Study used a prospective observational design with 91 individuals (82.4% female) enrolled in a challenge at three group fitness studios.
Class attendance data were provided by the studios for the 8 weeks before, during, and after the challenge.
Increases in attendance during the challenge were especially pronounced for those who previously attended fewer classes per week.
Prior exercise engagement moderated the degree of increase during the challenge.
Results
Increases in class attendance during the challenge were generally not sustained after the challenge ended.
Post-challenge attendance returned to the same or less than pre-challenge attendance levels.
This pattern suggests the challenge produced only a temporary increase in exercise engagement.
The study followed participants across three time periods: 8 weeks before, during, and after the challenge.
Results
Higher enjoyment motives attenuated declines in class attendance after the challenge.
Enjoyment motives were one of several key predictors of exercise behavior assessed via an online survey.
Other predictors assessed included prior exercise engagement, instrumental beliefs, and integrated regulation.
Only enjoyment motives were found to moderate post-challenge attendance declines.
This finding suggests enjoyment motives may be a meaningful factor in sustaining behavior change after program completion.
Results
Prior exercise engagement moderated behavior change during the challenge, with lower prior attenders showing greater increases.
Participants who previously attended fewer classes per week showed especially large increases during the challenge.
Prior exercise engagement was identified as a key predictor variable based on prior physical activity research.
This suggests gym-based challenges may have differential effects depending on participants' baseline activity levels.
Methods
The study examined individual-level predictors of exercise behavior including instrumental beliefs, enjoyment motives, integrated regulation, and prior exercise engagement.
Predictors were assessed via an online survey completed by challenge participants.
These predictors were identified based on prior physical activity research literature.
Ninety-one individuals completed the survey, of whom 82.4% were female.
The study used a prospective observational design rather than an experimental design.
Furman C, Volz S. (2026). Who stays for the after party? Examining predictors of exercise engagement during and after an 8-week gym-based body composition challenge.. Applied psychology. Health and well-being. https://doi.org/10.1111/aphw.70110