Background: There has been a noticeable decline in academic performance globally. This study examined the relationship between physical activity level, sleep quality, and academic performance among undergraduate students in Delta State, Nigeria. Methods: A cross-sectional descriptive survey was conducted using a multi-stage sampling technique and a structured, validated, self-administered questionnaire. Data were analyzed using chi-square tests, Pearson correlation, and multiple linear regression at p < 0.05. Results: 69.0% of the respondents had a moderate physical activity level. Mean sleep duration was 5.96 ± 1.40 hours; 57.2% reported good and 21.3% reported poor overall sleep quality. Mean CGPA was 3.30 ± 0.84. Physical activity level was significantly associated with sleep quality (χ² = 21.38, p = 0.001), and sleep quality was significantly associated with academic performance (χ² = 43.95, p = 0.001). Physical activity, sleep quality, and academic performance were positively correlated (r = 0.291-0.472, p < 0.01). Multiple regression showed that sleep quality (β = 0.418, p = 0.001) and physical activity level (β = 0.208, p = 0.001) jointly predicted academic performance, explaining 28.7% of its variance (R² = 0.287, F = 84.52, p = 0.001). Conclusion: Sleep quality and physical activity are significant, independent predictors of academic performance among undergraduate students in Delta State, with sleep quality exerting the stronger influence.
Keywords: physical activity; sleep quality; academic performance; undergraduate students