228. The regulatory effect of leisure cycling on emotion regulation and circadian rhythm stability in college students from the perspective of health behavior theory

Abstract Background The college student population widely faces dual challenges of emotional fluctuation and irregular sleep–wake patterns. Identifying feasible daily behaviors to promote their mental health has become a crucial issue. Health behavior theory suggests that regular, enjoyable, and low-threshold leisure activities are more likely to be adopted and sustained as health habits. Leisure cycling, as an active leisure form integrating physical exercise, social interaction, and outdoor exposure, is hypothesized to positively influence both emotion regulation and circadian rhythm. Based on the health behavior theory framework, this study aimed to investigate whether regular leisure cycling can effectively improve college students' emotional state and stabilize their circadian rhythm. Methods A total of 100 college students with emotional distress (Positive and Negative Emotion Scale [PANAS] negative emotion score ≥ 25) and self-reported irregular sleep–wake patterns were recruited and randomly assigned to a cycling intervention group (n = 50) or a wait control group (n = 50). The intervention group underwent moderate-intensity recreational cycling for 12 weeks, with at least 3 sessions per week and each session lasting no less than 40 minutes, preferably in a group setting. The control group maintained their original lifestyle. Assessments were conducted at baseline, week 6 of the intervention, and post-intervention. PANAS was used to evaluate emotional regulation, while the Pittsburgh Sleep Quality Index (PSQI) and Morningness-Eveningness Questionnaire (MEQ) were employed to assess circadian rhythm stability. Data analysis was performed using repeated-measures ANOVA. Results The comparison of symptom index between the two groups is shown in Table 1. As shown in Table 1, the cycling group's negative affect significantly decreased by the mid-intervention (T1, p<.001) and continued to improve post-intervention (T2). Concurrently, the intervention group's sleep quality significantly improved (lower PSQI score), and their circadian preference shifted towards a healthier "morningness" orientation (higher MEQ score). The results indicate that regular leisure cycling can synchronously regulate both the emotional and circadian systems. Discussion This study confirms that, from a health behavior theory perspective, leisure cycling is a feasible and effective regulatory activity. Its mechanisms may integrate the neuroendocrine benefits of exercise, the regulation of melatonin by natural light exposure, and the psychological support from social interaction. This research provides empirical and theoretical support for universities to promote non-competitive, pleasure-oriented group cycling activities to enhance students' overall psychosomatic health. Future research could further explore the differential effects of cycling frequency, duration, and environment (e.g., green spaces vs. urban streets) to optimize intervention protocols. Funding No. 202401001069.