Despite empirical evidence demonstrating the benefits of physical activity (PA) for mental health, the mechanisms linking PA and mental health remain uncertain. Thus, this study aims to investigate the mediating role of self-perception of PA and mental toughness in the relationship between PA and psychological well-being. In this cross-sectional study, a sample of 381 employed adults aged 21 to 42 years (M = 32.01, SD = 5.34; 64.53% female) completed scales measuring PA intensity, mental toughness, and psychological well-being, and reported their self-perceived PA level. Data was analysed using serial mediation analysis. The results indicated that PA’s direct contribution to psychological well-being was not statistically significant. The serial path of the mediation model revealed a statistically significant positive contribution of PA to psychological well-being via increased self-perception of PA and enhanced mental toughness. The findings suggest that the relationship between PA intensity and psychological well-being may be explained through individuals’ self-perception of their PA and their mental toughness. Specifically, those who engage in more intense PA also tend to perceive themselves as more physically active, which is associated with higher levels of mental toughness and ultimately contributes to enhanced psychological well-being.

physical activity, psychological well-being, self-perception, mental toughness, mental health