Effects of exercise snacks on physical and mental health among sedentary students: a randomized controlled trial study protocol.

UNLABELLED: Sedentary behavior is highly prevalent among university students and is associated with adverse cardiometabolic, inflammatory, and psychological outcomes. Exercise snacks (ES), generally conceptualized as brief, structured bouts of physical activity distributed across the day, have emerged as a time-efficient strategy for improving health, but evidence in sedentary university students remains limited. This study is the initial phase of a multiphase randomised controlled trial program and aims to evaluate the effects of a structured, campus-based stair climbing ES intervention on the physical and mental health of sedentary university students. In this two-arm, parallel-group, superiority trial with blinded outcome assessment and blinded data analysis, 60 sedentary university students will be randomly allocated to an ES group or a usual-lifestyle control group. The intervention consists of a 12-week structured stair-climbing ES programme, including an initial adaptation phase and an intensified progression phase. The primary outcome is maximal oxygen uptake (VO2max). Secondary outcomes comprise mental health and selected physical health measures, whereas exploratory outcomes comprise metabolic, inflammatory, and adipokine biomarkers. Intention-to-treat analyses will use analysis of covariance (ANCOVA) or log-ANCOVA, with primary inference based on baseline-adjusted between-group differences in VO2max. This trial will test a pragmatic, campus-based intervention in sedentary university students and may provide methodological and empirical support for campus-based student health promotion and subsequent experiments within the registered program. TRIAL REGISTRATION: https://www.chictr.org.cn/indexEN.html, identifier ChiCTR2500106549.