The Effect of Outdoor Activity Intention on Depressive Mood: The Mediating Role of Outdoor Activity Frequency

<b>Background:</b> With rapid urbanization, mental health challenges such as depression and emotional distress are becoming increasingly common. Contact with natural environments has been shown to improve mental health, yet most studies focus on direct associations between environmental exposure and mental health. The behavioral mechanisms underlying these benefits remain underexplored. This study aims to investigate whether outdoor activity frequency mediates the relationship between individuals' intention to engage in outdoor activities and depressive mood. <b>Methods:</b> We used data from the 2021 Chinese General Social Survey (CGSS). Drawing on the Theory of Planned Behavior (TPB) and supported by Stress Recovery Theory (SRT) and Attention Restoration Theory (ART), we constructed a mediation model. Ordinary Least Squares regression, ordered logistic regression, and mediation analysis were applied to assess the relationships among outdoor activity intention, activity frequency, and depressive mood. <b>Results:</b> The analyses revealed three main findings. First, outdoor activity intention alone did not directly reduce depressive mood. Second, outdoor activity frequency significantly alleviated depressive mood, suggesting that actual behavioral engagement with nature is critical. Third, the effect of outdoor activity intention on depressive mood was fully mediated by activity frequency. <b>Conclusions:</b> The results demonstrate that the mental health benefits of natural environments are not automatically derived from intention or preference but require active and frequent engagement. These findings provide empirical support for behavior-based interventions in urban mental health strategies and establish a theoretical foundation for future research on the pathways linking nature and mental health.