The moderating effect of mental toughness on the relationship between stress and mental health

Mental toughness (MT) is increasingly recognized as a psychological resilience factor that can help individuals to cope with stress more effectively and maintain better mental health. While previous studies suggest that MT buffers the negative effects of stress, it is unclear whether these patterns are consistent across broader adult populations and multiple dimensions of mental health.

This preregistered study examined whether MT moderates the relationship between perceived stress and three indicators of mental health: depressive symptoms, the mental health component of the SF-12 and subjective well-being. Participants were 402 community dwelling adults (aged 34-90) taking part in the longitudinal 'Gesundheit zum Mitmachen' project. MT, perceived stress, depressive symptoms, the mental health component, and subjective well-being were assessed using validated self-report instruments. Bivariate correlations and moderated regression analyses performed with Hayes' PROCESS macro for SPSS were conducted.

Higher levels of MT were associated with lower perceived stress and more favorable mental health outcomes, including fewer depressive symptoms, higher mental health component and higher subjective well-being. Perceived stress was strongly related to poorer mental health across all indicators. MT significantly moderated the relationship between stress and both depressive symptoms and the mental health component. However, the interaction term did not reach significance for subjective well-being, although the descriptive pattern suggested a similar buffering tendency.

The findings suggest that MT may be important in understanding individual differences in the association between perceived stress and mental health among community-dwelling adults. The observed pattern of results further supports the notion that the role of MT may vary across different mental health indicators rather than exerting uniform effects across outcomes. This is consistent with the view of MT as a context-dependent resource in stress appraisal and coping processes. Given the cross-sectional study design, the findings should be interpreted as associative rather than causal and require confirmation in longitudinal and experimental research.