Fit to learn: health and lifestyle predictors of academic performance in sports studies undergraduates.

INTRODUCTION: Academic achievement is typically treated as a single outcome, obscuring the differing demands of theoretical and practical coursework. We examined how health, sleep quality, fitness, energy drink consumption, and sport status relate to performance across course types. METHODS: Questionnaire data from 530 first-year kinesiology students (University of Zagreb, 2022/23-2024/25) were linked to official records of final grades in 11 courses. Ordinary least squares models with robust standard errors were estimated for overall GPA and six course-specific GPAs. RESULTS: Males scored 0.21 points lower than females, most markedly in theoretical courses. Better self-rated health and fitness predicted higher grades. Sleep quality was unrelated to overall GPA but positively associated with team-sport grades. Energy drink intake showed a U-shaped association; professional athletes underperformed in theoretical courses. DISCUSSION: Predictors of academic success operate differently across course types, supporting targeted academic support and health-promotion initiatives; the cross-sectional design precludes causal inference.