Can you ever REALLY catch-up on sleep?
In our hectic day and age, its one of the most common strategies for managing sleep: after a busy, sleep-deprived work week, many people use the weekend to catch up on their rest. Whether its sleeping in on the weekend mornings, or taking an afternoon nap, weekend are frequently a time when people try to bank extra sleep—to make up for not getting enough the week before and to prepare for sleep challenges of the week ahead.It’s a strategy that’s only partially successful. New research indicates that although some of the negative effects of a week of insufficient sleep can be remedied with extra sleep on the weekend, others cannot. Researchers at Penn State University College of Medicine studied the effects of weekend recovery sleep after a week of mild sleep deprivation. They found that make-up sleep on the weekends erased only some of the deficits associated with not sleeping enough the previous week.
The study included 30 healthy adult men and women who participated in a 13-night sleep laboratory experiment designed to mimic a sleep-restricted workweek followed by a weekend of recovery sleep. Participants spent four nights sleeping 8 hours a night in order to establish a baseline. They then spent 6 consecutive nights sleeping 6 hours nightly, an amount similar to what many working adults might expect to sleep during a typical week. Finally, volunteers spent a final 3 nights in recovery sleep mode, sleeping 10 hours a night. At several points throughout the 13-day study period, researchers tested the volunteers’ health and performance using several measures, including:
- Daytime sleepiness levels
- Attention span
- Inflammation, as measured by levels of interleukin-6 (IL-6), a biomarker for inflammation in the body
- Levels of the stress hormone cortisol
Their analysis showed weekend recovery sleep delivered mixed results. They found that 6 nights of restricted sleep led to significant deterioration across all but one measurement of health and performance. Two days of sleep recovery allowed for improvement to some, but not all, of those measurements:
- After 6 nights of sleep restriction, volunteers’ daytime sleepiness increased significantly. Two nights of recovery sleep brought levels of daytime sleepiness back to baseline measurements.
- IL-6, the marker for inflammation, also rose significantly during the 6-night sleep restriction period. Inflammation returned to baseline levels after recovery sleep.
- Cortisol levels did not rise or change during sleep restriction. However, after 2 nights of recovery sleep, cortisol levels dropped below measurements taken during the baseline phase of the experiment. Since cortisol levels are strongly linked to sleep duration, this finding suggests that the volunteers likely were already sleep deprived when the study began.
- Attention levels dropped significantly during the course of the mild sleep-deprivation period. Unlike the other measurements, attention performance did NOT rebound after a weekend’s worth of recovery sleep.
The takeaway? Relying on weekends to make up sleep lost during the week won’t fully restore health and function. In particular, you should not expect your attention and focus to bounce back after a couple of days of extra sleep. It’s important to note that this study measures the effects of only a single cycle of work-week sleep deprivation and weekend sleep recovery. The effects of an extended pattern of sleep deprivation and recovery followed by more sleep deprivation are not yet known. The benefits seen here in this study may not be replicated over the long term.
This isn’t to say that recovery sleep can’t be useful and effective. As this study shows, on a short-term basis catching up on sleep can reverse some of the problems associated with insufficient rest. Getting extra sleep on a weekend after a particularly busy, sleep-scarce week is one option. Naps are another. Studies show that napping after a single night of sleep deprivation also can reverse some of the adverse effects of sleep loss. Research also indicates that a combination of naps and overnight recovery sleep can be effective in counteracting some negative effects of sleep deprivation.
Recovery sleep can be a useful short-term or occasional strategy. But the best sleep strategy is one that avoids sleep deprivation as a regular occurrence. It doesn’t take long for the adverse effects of insufficient sleep to appear. The health consequences of just a week of mild sleep deprivation can be seen in the current study and in other research, which shows insufficient sleep associated with diminished cognitive performance, reduced alertness, and mood problems. Modest sleep deprivation increases inflammation, interferes with healthy immune function, triggers metabolic changes and drives up the impulse to overeat. Even a single night of partial sleep deprivation can increase insulin resistance, disrupt hormone levels, and elevate blood pressure.
None of us may be able to avoid the occasional night or period of insufficient sleep. But a healthy work-week sleep routine can and should leave you with nothing sleep-related to catch up on when the weekend arrives.
Michael J. Breus, PhD
The Sleep Doctor®