Understanding risk acceptance in performance enhancing substance use: A cluster randomized prevention study among...

The use of performance-enhancing substances such as pre-workout supplements has become increasingly common in recreational fitness environments. Although behavioral interventions aim to reduce enhancement-related substance use, little is known about whether such interventions operate similarly across different psychosocial athlete profiles and which psychological mechanisms may underlie behavioral change.

Data were analyzed from a cluster-randomized prevention trial conducted in ten fitness studios in Germany, including 602 recreational fitness athletes. Cluster-adjusted logistic regression models examined intervention effects on booster use at follow-up (T3). Moderation analyses tested differential responsiveness across psychosocial athlete profiles, while mediation analyses examined changes in risk acceptance as a potential psychological pathway.

Participants in the intervention group showed lower odds of booster use compared with the control group (OR = 0.58, 95% CI [0.33, 1.00], p = .052), corresponding to an absolute risk reduction of 6.65 percentage points. Risk acceptance decreased more strongly among motivationally ambivalent athlete profiles, whereas comparable moderation effects were not observed for booster use. These reductions were consistent with a partial mediation pathway linking the intervention to reduced booster use.

The findings suggest that behavioral interventions in recreational fitness settings may operate differently across psychosocial athlete profiles rather than producing uniform effects. Changes in risk acceptance appear to represent a key psychological mechanism associated with intervention-related reductions in booster use, highlighting the importance of psychologically informed prevention strategies tailored to psychosocial athlete profiles in recreational fitness populations.