This study explored the determinants of sustained participation in new sports by applying the Theory of Planned Behavior (TPB) and examining the moderating role of social support, as well as the influence of media interest. This present study aimed to contribute to the promotion and effective adoption of new sports by providing valuable data for new-sports educators to teach these activities. A survey was conducted among 313 university students enrolled in new-sports classes across five universities in Korea, utilizing a convenience sampling method. Using SPSS 26.0 and AMOS 26.0, we conducted frequency, correlation, and reliability analyses, followed by confirmatory factor analysis (CFA) to validate the measurement model and structural equation modeling (SEM) to examine the relationships between media interest, attitudes, subjective norms, perceived behavioral control (PBC), and behavioral intentions. The software Jamovi version 2.3.21 was employed to analyze the moderating effects of social support from educators on these relationships. The findings reveal that media interest significantly influenced the attitudes, which, in turn, along with subjective norms and PBC, affected the behavioral intentions. Moreover, the social support from educators moderated the effects of attitudes, subjective norms, and PBC on the behavioral intentions. This study concluded that leveraging media interest and enhancing social support can effectively promote engagement and sustained participation in new sports. These insights can offer practical strategies for stakeholders aiming to increase participation rates in new-sports activities.