RESUMO
Aims: To evaluate the associations between bedtime initiations, sleeping sufficiency and objective academic performance in a large sample of second secondary students.Methods: Thestudy sample consisted of 900 adolescents; 450boysand 450 girls in the second secondary class at Hail city in the Kingdom of Saudi Arabia.Participants filled a questioner about their socioeconomic factors as bedtime, sleeping duration, mental games practicing, and physical activity.Weight and heightwere measured to assess body mass index (kg/m2). Data extracted from the questioner used to study the contribution of the concomitant factors on academic achievement.Results: The mean weight was 73.57±8.34kg IQR (44-126) while the mean height was (170.38±6.45) cm IQR (141-192). The mean BMI was 33.57±14.79(IQR 21.0–38.8). The overall prevalence of childhood obesity was 460 (49.6%; 95% CI: 55.3–66.8%) while the prevalence of overweight was 85 (9.04%; 95%CI: 7.3 –11.4%). The mean ministry academic score for the second secondary class was 70±9.99 IQR (44-99) while the school academic score was 88.07±7.44 IQR (60-99).51.6% of the students went to bed between 10-12 pm and only 17.6% slept between 8 and 10 hours.Conclusion: We can summarize, the independent variables as bedtime, sleeping duration, and obesity ameliorate academic achievement in a counteractive way; high BMI above 35 and prolonged sleeping duration more than 10 hours significantly curb the total academic score, whereas, healthy bedtime of 8-10 pm concomitantly augment the academic achievement