by Sheryl Hemphill, PhD
Increasing knowledge of the sleep patterns of adolescents has important implications for education. Research around the world has shown that the sleep patterns of adolescents are delayed – their natural sleep time is 11pm or later and they then want to wake later. Given that they require about 8 ½ to 9 ¼ hours of sleep per night and also need time to eat breakfast and commute to school, arriving on time to morning classes is challenging.
To arrive at school on time (or close to that), students can accumulate a sleep debt during the school week and report sleepiness during the day. We all know from our own experience that not having enough sleep and feeling tired affects concentration and mental processing. There is a growing awareness of the potential effects on adolescents of not having enough sleep. These include an increased likelihood of accidents and injuries, diminished learning, loss of memory, behaviour problems, changes in metabolism, and weight gain.
One potential solution is to delay school start times so that secondary school students can have adequate sleep. Later school start times take into account the sleep needs of teenage students, the impact of sleep deprivation, the times during which teenage students are most alert, and the times of day that are best for learning. A particular question of interest, then, is whether later school start times offer benefits to student sleep, health, and learning.
What the research tells us?
There have now been a few systematic reviews and/or meta-analyses that have examined the effects of delayed school start times on student outcomes. One such review was conducted in 2017 by Marx and colleagues from the United States of America, Canada, and India. This review attempted to bring together the results of studies on the impact of later school start times on student health, education, and wellbeing.
The researchers found 17 studies that had examined this question. However, they noted the generally poor quality of these studies – it’s not easy to conduct such research in schools.
Despite the limitations to the quality of the studies, they found:
There were six studies that showed the amount of sleep of students increased with later school start times.
The results of studies on other student outcomes were inconsistent. For example, four studies examined associations with academic outcomes but there wasn’t a clear pattern in the results. There were only three studies on student alertness and the effects of later school start times on student alertness were unclear. There was just one study on mental health outcomes and that showed a reduction in depressive symptoms.
There was limited information on the practicalities of later school start times such as the implications for family life and any difficulties associated with staffing and scheduling later school start times.
The results of this review underline the importance of further high-quality research in this area.
Sleep is now considered a priority to maintain good health just like eating well and exercising. This is important not only for adolescents but also for all of us. Many adults are themselves sleep-deprived. One way to overcome some of the perceived obstacles (e.g., impact on transport and parents’ work) to later school start times might be to acknowledge the problem of sleep deprivation more broadly in our community living in our modern world. Perhaps it’s time for a discussion about the ways we can promote sleep hygiene for all members of the community to improve our health and then adjust our lifestyles accordingly.
Sheryl Hemphill, PhD, is a freelance writer, presenter, and researcher focusing on sharing research findings with schools and the broader community. She holds Adjunct/Honorary positions at La Trobe University, the University of Melbourne, and Murdoch Children’s Research Institute.