Could later school start time improve adolescents’ sleep habits and general well-being?

Underestimating and neglecting the importance of sleep for adolescents can result in a huge negative impact on their health and well-being¹. Research indicates that some small policy changes could improve adolescents’ sleep habits and reduce daytime tiredness as well as improving mood.  Research has found that a later start to the school day can help improve adolescents’ well-being in several different ways ^{1, 2, 3,4}.

One US study² investigated the impact of delaying school start time by 30 minutes on students’ self-reported sleep, daytime tiredness, activity motivation and depressed mood. The study involved 278 students at a private boarding school who were surveyed before and after the introduction of the delayed school start time. After two months students reported sleeping longer, feeling less tired during the day, and scored lower for depression. Further, motivation for engaging in various activities increased.

In Switzerland in a sample of 2716 adolescents (mean age: 15.4 years) the relationship of sleep duration with  positive attitude towards life and academic achievement were examined ³.  The  study  indicated that students in a school that started 20 minutes later than the other schools, reported getting 16 min more sleep on school nights, which was  associated with less tiredness during the day. The authors recommend a short delay of school start times by 20 min which will have a substantial effect on adolescents’ sleep duration and daytime tiredness.

The most interesting experiment was conducted   in America on a sample of more than 9000 adolescents from a single, large, county-wide, school district: adolescents’ sleep habits and motor vehicle crash rates were assessed by questionnaire before and after a 1-hour delay in school start times⁴. It was found that a 1 hour delay in school start time resulted in increases in average hours of nightly sleep and decreases of catch-up sleep on weekends. Also average crash rates for teen drivers in the same county in the 2 years after the change in school start time dropped 16.5%, compared with the 2 years prior to the change, whereas teen crash rates for the rest of the state increased 7.8% over the same time period.

Unlike the USA, the UK has not systematically evaluated experiments to change the school start time, although three secondary schools in North Tyneside and Kent have tested a later start time of 10am and have reported  anecdotal information on reductions in absence and persistent absenteeism¹.

In the UK most secondary schools start at 8.30am, though there are number of schools starting at 9.00am. Based on current research, we might recommend policy makers to make further changes in school start times at least for half an hour, if not an hour. Meanwhile it would be interesting to compare the sleep habits and well-being of adolescents from those schools starting at 9am to those ones who start school earlier.

                                                                                                                        Ellen Klemera

1. www.ayph.org.uk
2. Owens, J. A., Belon, K., & Moss, P. (2010). Impact of delaying school start time on adolescent sleep, mood, and behaviour. Archives of Pediatrics & Adolescent Medicine, 164, 608–614.
3. Perkinson-Gloor ,N., Lemola,L., Grob,A.(2013) Sleep duration, positive attitude toward life, and academic achievement: The role of daytime tiredness, behavioural persistence, and school start times, Journal of Adolescence, January 2013.
4.  Danner F and Phillips B (2008) Adolescent sleep, school start times and teen motor vehicle crashes,Journal of clinical Sleep Medicine, 4, 533-535