Having kids (and a dog with a small bladder) has changed my perspective on what “normal” bedtime and wakeup times look like. But in my college years, 2am seemed like a pretty normal bedtime.
I mean, the conservatory building closed at 11pm, and the snack bar was on the way back to my dorm, so it made perfect sense to stop by and grab a sandwich, some chili, and a giant cookie, to fuel up for some 4-player Mario Kart with my roommates.
Of course, when you combine late-night grease, chili, sugar, Mario Kart, and a 2am bedtime, the result is a natural wakeup time of something in the neighborhood of 10 or 11am.
So when summer came around, 9am summer festival orchestra rehearsals were kind of rough. My fingers would feel sluggish, my brain would be in a fog, and it wasn’t until rehearsal wrapped up around noon that I started to feel like my normal self.
At the time, I assumed I was just more of a night owl, and that morning rehearsals simply didn’t jibe with my natural body clock.
But a recent study suggests that our circadian rhythms are actually somewhat malleable.
That you can train yourself to become more of a “morning lark,” shift your peak performance window to earlier in the day, and enjoy not just a boost in performance, but perhaps even in mood as well.
A sleep study
A team of British researchers (Facer-Childs, Middleton, Skene, & Bagshaw, 2019) recruited 22 participants to participate in a sleep study.
Using a variety of questionnaires, saliva samples (to measure melatonin1 and cortisol2) and actigraphs3, the researchers started out by measuring participants’ baseline mood levels (i.e. depression, anxiety, stress, etc.) and tracking their normal sleep/wake patterns for two weeks.
Once they established a baseline, the participants returned to the lab for tests of grip strength and reaction time. And to get a sense of what time exactly during the day they might be at their mental and physical “peak,” the tests were repeated at 8am, 2pm, and 8pm.
Then, one group (experimental group) was given a set of specific instructions to follow for the next three weeks, including when to sleep, when to eat, when to get light, and so on.
The other group (control group), was simply told to “eat lunch at the same time every day.”
After three weeks of following these instructions, everyone returned to the lab one last time to get tested again, and see if there were any changes to their grip strength, reaction time, and mood.
So did anything change?
Yes! And in three key areas.
For one, the 3-week sleep program was successful in shifting the participants’ sleep schedules to earlier wake and sleep times.
Because while the control group’s sleep and wake times ended up getting even later for some reason (from a baseline of 1:37am-9:37am at the beginning of the study to 2:47am-10:51am by the end of the study), the experimental group exhibited a “phase advance” of about 2 hours. They started with a baseline sleep schedule of 2:46am-10:31am, but by the end of the study, had shifted to a new sleep schedule of 1:03am-8:46am.
This change was also reflected in their melatonin (associated with sleep) and cortisol (associated with awakening) levels. Melatonin onset shifted from a baseline of 12:02am, to 10:04pm by the end of the study. And their cortisol awakening response shifted from 11:19am to 9:06am as well.
And most importantly perhaps, the experimental group’s sleepiness scores indicate that not only were they able to successfully shift their sleep schedule, but they were also more alert and less sleepy at both 8am and 2pm, than they were before changing their sleep schedule.
Which sounds promising – but did this translate into any changes in physical or cognitive performance?
Well, the experimental group’s grip strength at 8am in the morning did improve significantly4. And though I’m not sure if there’s any relationship between grip strength and finger dexterity, it’s still nice to see some evidence of physical change from the phase advance.
And in terms of cognitive performance, their 8am reaction time scores also improved significantly from baseline to their final test following the three-week phase advance.
Meanwhile, the control group’s physical and mental scores stayed the same.
Finally, the phase advance also seemed to contribute to an improvement in some measures of well-being.
Previous studies have observed a link between later sleep times and some measures of depression. Likewise, in this study, the earlier sleep and wake times were associated with a decrease in scores related to depression and stress, while the control group’s scores in these areas stayed the same.
So all in all, if you have been keeping night owl hours, and would like to be more of a morning person, it’s totally possible.
And not only will you be more alert and perform more at your peak in those early morning summer festival rehearsals, but it might have some benefits to your general well-being too!
So what exactly did the experimental group change in their daily routine?
The 3 week phase advance instructions
Here’s exactly what they were asked to do:
- Wake up time: Wake up 2-3 hours before your normal wakeup time
- Bedtime: Try to go to sleep 2-3 hours before your normal bedtime
- Consistency: Maintain the same daily wake/sleep times (within ~15-30min) – even on weekends
- Light exposure: Maximize light exposure (outdoors) during morning hours
- Meals: Keep a consistent schedule for meals; eat breakfast as soon as possible after waking up. Eat lunch at the same time every day. And no dinner after 7pm.
- Caffeine: No caffeine after 3pm
- Naps: No naps after 4pm
- Exercise: If you exercise, do so only in the morning, not in the evening.
Facer-Childs, E. R., Middleton, B., Skene, D. J., & Bagshaw, A. P. (2019). Resetting the late timing of “night owls” has a positive impact on mental health and performance. Sleep Medicine.
- a hormone associated with getting to sleep
- a hormone associated with waking up
- These are a bit like smart watches that collect data about your sleep patterns
- And at 2pm as well, for what it’s worth