I recently wrote an article that emphasized the importance of sleep over food when applied to monophasic sleep (sleeping in one chunk of time). The rules governing polyphasic sleep (sleeping in multiple chunks of time) are a world apart but stem back to a common question:
How little sleep do I need before my overall performance gets compromised?
While acute sleep deprivation has an immediate effect, 17 hours without sleep leaves you as impaired as a blood alcohol content of .05, and 24 hours without sleep equal to a blood alcohol content of .10¹; chronic sleep deprivation is insidious. Missing even an hour every night leaves you functionally impaired but feeling fine.²
By comparison, the benefit of polyphasic sleep is seductive: Reduce total sleeping time from 7.5-9 hours a day to 6.5 hours or even 2 hours, without sacrificing mental or physical performance.
How does it work?
The human body goes through stages in sleep. To feel rested and function cognitively, the human body needs REM (Rapid Eye Movement) sleep. To heal and recover physically, it needs NREM (None Rapid Eye Movement) and SWS (Slow Wave Sleep) sleep.
EEG’s of monophasic sleep show that about 1.5 hours are spent in REM sleep. However, after extended periods of sleep deprivation, the brain drops into REM sleep faster. Polyphasic sleep works because even though total sleeping time is reduced, the time in REM sleep stays the same.
Common Polyphasic Sleep Techniques:
– Uberman: The original polyphasic sleep cycle. Twenty minute naps every 4 hours. That’s only 2 hours of sleep every 24 hours. The adjustment period is short but brutal. It allows no flexibility in nap timing.
– Everyman: Total sleep time depends on the variation used, but the most common involves one “core” sleep of 3 hours and three 20 minute naps spaced out during the day. The adjustment period is much longer but less brutal. While there is a degree of flexibility in nap timing, it can’t be tweaked until the schedule is properly ingrained (which takes about a month).
Why would anyone do it?
Time. With the Everyman cycle, you potentially get another 1.5 hours out of your day. With the Uberman cycle, you get 22 hour days. Which can be very powerful if leveraged correctly. A military that can operate with little sleep without error can run more operations, more frequently and with timing that completely clashes with that of their enemy.
Minimizing errors. The Vendée Globe is a 4 month long one-person roundtrip boat race from France around Antarctica. Errors while awake and oversleeping can cost sailors their lives. Physicians work long hours with irregular sleep patterns. The longer they stay awake, the longer they run the risk of making serious medical and diagnostic errors.
– There’s an adjustment period. It can last a month and for the first week you’ll barely function. Forget trying to learn anything. Microsleep and mental confusion will be constant companions.
– It’s difficult to apply to modern life. You need fanatical dedication to the sleep schedule you set up. If you miss a nap, you’ll be tired for days.
– There’s a physical toll. Symptoms like nausea, dizziness, slower reaction times, and weight change (either loss or gain) will appear.
– You can’t consume anything that affects sleep. That means no caffeine, alcohol or nicotine. Each of these affect the amounts of REM and NREM sleep you get. Anything that might jeopardize nap timing or change that ratio has to be avoided.
NOTE: There is a meta-analysis that correlates an increase in NREM sleep with infection³ but a direct link between quantity of REM sleep, NREM sleep and total immune function still isn’t clear. Either way: if you’re sick, sleep normally.
Is a polyphasic sleep schedule feasible?
– Short Term (+/- one week): Yes. It’s been tested by soldiers, boat crews, and masochistic bloggers.
– Long Term (6 months): Depends on the individual and their commitments. Two of the most comprehensive long term polyphasic sleep logs are from Steve Pavlina and Pureoxyk (who literally wrote the book on the Uberman sleep cycle).
So it’s feasible. Whether it’s feasible in high level athletes is slightly more complicated. Two factors that come up are the impact of a very low carbohydrate diet on the ratio of REM/NREM sleep and the relationship between physical performance and sleep deprivation.
More on these after tests and research.
1) Quantitative similarity between the cognitive psychomotor performance decrement associated with sustained wakefulness and alcohol intoxication. Here
2) The Cumulative Cost of Additional Wakefulness: Dose-Response Effects on Neurobehavioral Functions and Sleep Physiology From Chronic Sleep Restriction and Total Sleep Deprivation. Here
3) How (and why) the immune system makes us sleep. Here
4) Why we nap – Claudio Stampi Here (He’s the original sleep researcher)
5) Ubersleep: Nap-Based Sleep Schedules and the Polyphasic Lifestyle – Pureoxyk Here