0221 Time to wake up! Adolescents woken up by an alarm or family member get short sleep on schooldays and weekends/holidays

Abstract Introduction Many adolescents get insufficient sleep on schooldays because they need to wake up early. It is often assumed that students can in longer non-schooldays (weekends and holiday periods) recover their debt. However, few studies have explored the degree which are given freedom extend nocturnal sleep. Here, (1) we investigated how awoken by an alarm or family member non-schooldays, (2) tested whether this results shorter even non-school days. Methods Adolescents aged 13-18 years (n=66; 10 schools Singapore) wore actigraphy watch (Actigraph wGT3X-BT) completed daily diaries for 7 days during school periods. Each morning, indicated reason having woken. Actigraphy-derived parameters included onset, offset, period. Simple effect sizes (e.g., mean difference period) were calculated versus waking other reasons. Results Adolescents’ was about 1.7 hours (mean=6.50h, 95% CI=6.24h-6.75h) compared with (mean=8.17h, CI=7.89h 8.45h) woke much earlier. Students 78% of schooldays, associated reasons (mean period=-1.16h, CI=-1.59h -0.80h). By comparison, 41% non-schooldays. In such instances, also obtained hour period=-1.21h, CI=-1.46h -0.94h) slept less than recommended amount age group period=7.38h, CI=7.18h 7.59h). Conclusion frequently interrupted both Chronic restriction extends beyond if not allowed naturally ‘free days’. This may deleterious effects students’ performance wellbeing. Support (if any) The research funded National Institute Education, Singapore (OER 14/21 JJG).