Who sleeps worse and why? An analysis of sex, chrononutrition, anxiety, and sleep in adolescent athletes

This study investigated how anxiety and chrononutrition are related to sleep in male and female adolescent athletes. In total, 460 adolescent athletes (14.7 ± 1.5y; 38% female) completed the Pittsburgh Sleep Quality Index (PSQI), State-Trait Anxiety Inventory (STAI-S), and Chrononutrition Profile Questionnaire. Outcomes included anxiety, sleep and chrononutritional patterns, and misalignment between actual and preferred sleep and dietary schedules. Females showed shorter weekday sleep, greater weekly sleep-duration misalignment, and later weekly average breakfast timing, alongside narrower eating windows, than males. Across STAI-S categories, sleep duration decreased, breakfast time was later, and the eating window shortened (all, p < 0.01). In hierarchical regression, STAI-S was the strongest correlate of poorer PSQI; each 10-point higher STAI-S related to +2.63 PSQI (p < 0.001) and later breakfast time was independently related to worse PSQI (+0.30 per +60 min; p = 0.016). In mediation analysis, the sex difference in PSQI was largely accounted for by higher anxiety in females. Overall, poor sleep quality was related to higher anxiety and later breakfast timing. Females were disproportionately affected, and the sex gap in sleep quality was largely explained by higher anxiety. These findings highlight the need to address chrononutritional habits and anxiety to improve sleep, with particular attention to female adolescent athletes.