Abstract
Ultimate frisbee is a peer-regulated sport in which self-officiation makes interpersonal interaction integral to participation. Guided by Self-Determination Theory, this study examined cross-sectional structural associations among Group Climate, Autonomous Motivation, and global Flow Experience in 368 ultimate frisbee participants in China. Group Climate reflected Engagement and the relative absence of Conflict. Participants completed Chinese-language measures of group climate, sport motivation, and flow; confirmatory factor analysis, structural equation modeling, and bootstrap procedures were used. In the retained direct-plus-indirect model, Group Climate was positively associated with Autonomous Motivation (β = 0.863, p < .001), Autonomous Motivation with Flow Experience (β = 0.578, p < .001), and Group Climate retained a positive residual association with Flow Experience (β = 0.346, p < .001). The standardized indirect association through Autonomous Motivation was 0.499 (percentile 95% CI [0.309, 0.739]; bias-corrected sensitivity CI [0.299, 0.728]). Together, these findings identify a coherent social-motivational pattern in which perceived interactional climate, Autonomous Motivation, and Flow Experience are closely linked within ultimate frisbee. By integrating group-process and motivational perspectives in a peer-regulated sport context, the study extends SDT-informed sport research and provides a focused framework for examining how interpersonal interaction and motivational quality relate to optimal experience.