'Night owls' can retrain body clock to improve health and performance

Research by Monash University shows that a simple tweak to the sleeping patterns of 'night owls' could improve their overall quality of life.

A simple tweak to the sleeping patterns of ‘night owls’ – people with extreme late sleeping and waking habits – could lead to a significant advance in sleep/wake timings, a decrease in depression and stress, improved performance in the mornings and better eating habits.

New international research by Monash University, University of Birmingham and the University of Surrey (UK) shows that, across a three week period, it was possible to shift the circadian rhythm of ‘night owls’ using non-pharmacological and practical interventions.

The study, published in Sleep Medicine today (Monday 10 June 2019), showed participants were able to bring forward their sleep/wake timing by two hours, while having no effect on sleep duration. In addition, participants reported a decrease in feelings of depression and stress, as well as daytime sleepiness.

As our body clocks continue to fluctuate in response to flexible work, family and social arrangements, which impact on sleep timing, quantity and quality, adopting regular sleep, meal and exercise times can make us happier, more productive and less stressed, the study reveals.

This intervention could also be applied within more niche settings, such as industry or within sporting sectors, which have a key focus on developing strategies to maximise productivity and optimise performance at certain times and in different conditions.

“Our research findings highlight the ability of a simple non-pharmacological intervention to phase advance ‘night owls’, reduce negative elements of mental health and sleepiness, as well as manipulate peak performance times in the real world,” lead researcher Dr Elise Facer-Childs from Monash University’s Turner Institute for Brain and Mental Health said.

“In clinical settings, further treatments for mental health and depression could be explored targeting sleep and circadian rhythms without the need for medication.”

‘Night owls’ are individuals whose internal body clock dictates later-than-usual sleep and wake times, with an average bedtime of 2.30am and wake-up time of 10.15am in this study.

Disturbances to the sleep/wake system have been linked to a variety of health issues, including mood swings, increased morbidity and mortality rates, and declines in cognitive and physical performance.

According to data from the Australian Bureau of Statistics, there were approximately 1.7 million Australians doing some kind of shift work as part of their main occupation in 2015. More than 60% of Australians are constrained to a regular 9-5 working day, but for up to 40% of these who could be ‘night owls’, this could be negatively impacting them.

“Having a late sleep pattern puts you at odds with the standard societal days, which can lead to a range of adverse outcomes – from daytime sleepiness to poorer mental wellbeing,” study co-author Dr Andrew Bagshaw from the University of Birmingham said.

“We wanted to see if there were simple thing people could do at home to solve this issue. We now need to understand how habitual sleep patterns are related to the brain, how this links with mental wellbeing and whether these interventions lead to long-term changes.”

Twenty-two healthy individuals participated in the study. For a period of three weeks participants in the experimental group were asked to:

  • Wake up 2-3 hours before regular wake up time and maximise outdoor light during the mornings.
  • Go to sleep 2-3 hours before habitual bedtime and limit light exposure in the evening.
  • Keep sleep/wake times fixed on both work days and free days.
  • Have breakfast as soon as possible after waking up, eat lunch at the same time each day, and refrain from eating dinner after 7pm.

Results highlighted an increase in cognitive (reaction time) and physical (grip strength) during the morning when tiredness is often very high in ‘night owls’, as well as a shift in peak performance times from evening to afternoon. It also increased the number of days in which breakfast was consumed and led to better mental wellbeing.

“Establishing simple routines could help ‘night owls’ adjust their body clocks and improve their overall physical and mental health. Insufficient levels of sleep and circadian misalignment can disrupt many bodily processes putting us at increased risk of cardiovascular disease, cancer and diabetes,” Professor Debra Skene from the University of Surrey said.

Dr Facer-Childs said ‘night owls’, compared to ‘morning larks’, tended to be more compromised in our society due to having to fit to work/school schedules that are out of sync with their preferred patterns.

“By acknowledging these differences and providing tools to improve outcomes we can go a long way in a society that is under constant pressure to achieve optimal productivity and performance,” she said.

The study was led by Dr Elise Facer-Childs (Monash University) with support from Dr Benita Middleton and Professor Debra Skene (University of Surrey), and Dr Andrew Bagshaw (University of Birmingham).