Predictors of long-term resistance exercise adherence among beginners: Evidence from a large cohort of mobile app users

Background:Digital fitness applications offer unprecedented access to structured training programs, yet the behavioral factors that predict sustained engagement in real-world settings remain incompletely understood. Methods:This observational study analyzed data from 522,994 adult digital fitness app users (mean age: 34.2 ± 9.8) of various experience levels followed for six months from their first recorded workout.Long-term adherence was defined as completing at least one workout per week, allowing up to three missed weeks.Adherence trajectories were examined, along with associations between early training behaviors (training frequency, workout duration, exercise composition, equipment diversity), demographic factors, and time to dropout.Effect modifications by sex, workout duration, and training experience were also investigated. Results:Adherence declined steadily over time, with 18.1% of beginner users remaining adherent at 6 months.The median dropout time was 14 weeks.Higher sustained participation was observed in older versus younger (51+: 23.8%; 18-40: 15%), male versus female (M: 19.9%; F: 15.2%), and more experienced users (intermediate: 28.6%; advanced: 38.2%).Training consistency during the first 28 days was the strongest predictor of adherence and exhibited a protective association that attenuated over time.Greater diversity in equipment use and higher emphasis on resistance exercise were also associated with lower dropout risk.Longer workout duration was associated with improved adherence among users who trained more frequently, particularly early in follow-up. Conclusions:Early consistency and structured training behaviors were strongly associated with long-term adherence among beginners, with relatively modest differences based on age and sex.These findings suggest that frequent training sessions and engagement with resistance-based exercise during the initial stages of exercise adoption may be relevant behavioral correlates of sustained engagement.