In February, scientists revealed hard evidence that night owls have a biological handicapped when it comes to the 9-to-5 workday. Fortunately, research published Sunday in Sleep Medicine offers a way for night owls can fight back against their natural circadian rhythms, making mornings a lot more tolerable.
A randomized controlled trial conducted by scientists at the University of Birmingham in England and Monash University in Australia showed that it’s possible for night owls to hack their own deep-seated biological rhythms. By adhering to the routine designed by these scientists, 22 “night owls” were able to shift their internal rhythms by an average of two hours.
After following the steps laid out by scientists for three months, night owls reported feeling better during the day, added Andrew Bagshaw, Ph.D., a study co-author and co-director of the University of Birmingham’s Center for Human Brain Health.
“We wanted to see if there were simple things people could do at home to solve this issue. This was successful, on average allowing people to get to sleep and wake up around two hours earlier than they were before,” he said. “Most interestingly, this was also associated with improvements in mental wellbeing and perceived sleepiness, meaning that it was a very positive outcome for the participants.”
The new research is based on the fact that the sleeping habits of night owls, technically people with “late chronotypes,” are based in distinct biological characteristics and not just negligence about sleep hygiene. There are certain genetic patterns that influence sleep and wake times, resulting in two main chronotypes: night owls, who feel more alert late in the day, and “morning larks”, who have those peaks earlier.
In the paper, the scientists guided 22 people with late chronotypes as they tried to develop a technique to hack their internal clocks. The experimental group was told to:
- Wake up between two and three hours earlier than they typically would.
- Eat breakfast right away.
- Try to maximize exposure to natural light during waking hours.
- Avoid caffeine after 3 p.m., napping after 4 p.m., and eat dinner before 7 p.m.
- If they normally exercised, they were told to work out in the morning, not in the afternoon.
This rather involved schedule is based on earlier research on light exposure, meal timing, and exercise. Changing each of these factors has been shown to tweak different aspects of circadian rhythm, the internal 24-hour cycle of sleep and wakefulness that’s governed by the “master clock” in the brain but is also present in peripheral clocks in every cell in the body.
In the experimental group, keeping with the routine laid out by the researchers successfully created a “phase advancement” that resulted in earlier sleep/wake times. The authors posit that this was caused by a shift in the release of hormones that control circadian rhythms to a cycle that began two hours earlier in the day.
For example, after the experimental period, the release of melatonin (a hormone responsible for sleepiness) in night owls began around 10:04 p.m. as opposed to their usual 12:02 a.m., suggesting that night owls began to feel tired earlier. Meanwhile, jumps in cortisol, a hormone that’s released upon waking, spiked earlier too — around 9:06 a.m. as opposed to the usual 11:19 a.m.
These shifts in the night owls’ sleep/wake cycle were accompanied by increased reaction time and grip strength compared to the control groups, suggesting that the night owls were more awake and alert after they followed the routine. The night owls themselves reported more wakefulness — specifically noting lower ratings of daytime sleepiness around 8 a.m. and 2 p.m.
The method wasn’t perfect — night owls still felt sleepiest in the morning — but waking up felt less jarring for them, according to the numerical scale used to measure sleepiness. Before the experiment, the night owls reported “some signs of sleepiness in the morning” but after they switched up their routines, they claimed to feel “rather alert” in the morning.
These changes are fairly demanding — especially for people who balk at the idea of eating an early breakfast or can perform better when working in the afternoon. But for those who are ready to commit to them, there’s solid evidence that it really is possible to shift a sleep-wake schedule by two hours that also continues to pay off later in the day.
In other words, it’s a “simple strategy” for night owls who are looking for a change, the authors add.
“Within the general population, of which a large proportion are night owls, “ they write, “these findings could offer a simple strategy to improve mental well-being and performance.”
Abstract: There is conflict between living according to our endogenous biological rhythms and our external environment, with disruptions resulting in negative consequences to health and performance. This is often documented in shift work and jet lag, but ‘societal norms’ e.g. typical working hours, can create profound issues for ‘night owls’, people whose internal biological timing predisposes them to follow an unusually late sleep-wake cycle. Night owls have also been associated with health issues, mood disturbances, poorer performance and increased mortality rates. This study used a randomized control trial design aimed to shift the late timing of night owls to an earlier time (phase advance), using non pharmacological, practical interventions in a real-world setting. These interventions targeted light exposure (through earlier wake up/sleep times), fixed meals times, caffeine intake and exercise. Overall, participants demonstrated a significant advance of ~2 h in sleep/wake timings as measured by actigraphy and circadian phase markers (dim light melatonin onset and peak time of the cortisol awakening response), whilst having no adverse effect on sleep duration. Importantly, the phase advance was accompanied by significant improvements to self-reported depression and stress, as well as improved cognitive (reaction time) and physical (grip strength) performance measures during the typical ‘suboptimal’ morning hours. Our findings propose a novel strategy for shifting clock timing towards a pattern that is more aligned to societal demands that could significantly improve elements of performance, mental health and sleep timing in the real world.