Polyphasic Sleep Beginner’s Guide

We often think of ideal sleep as eight hours a day, once a day. This is called monophasic sleep, but it may not be the most natural or ideal way to sleep. Instead, a polyphasic sleep schedule, or a daily schedule with more than two rests, can help you sleep more efficiently—more sleeping in fewer total hours.

What Is Polyphasic Sleep?

Although the polyphasic sleep schedule may sound unusual or even impractical, people who take brief naps during the day or split up their nighttime sleep are doing so every day. To better understand how more naps during the day can actually lead to fewer hours of sleep and better rest, let’s dive deeper into the science behind polyphasic sleep. (If science puts you to sleep, don’t worry—we’ll make it quick).

Sleep Stages 101

The TLDR of polyphasic sleep is that we all need daily rest, but splitting up our sleeping hours into multiple naps lets us spend more hours in deeper, more restorative sleep stages but with fewer total hours in bed. So, doing more sleeping in less time leads to a higher sleep density.

The reason a higher sleep density can allow you sleep less total hours is because not all sleep stages are created equal. So, let’s take a look at the different sleep stages (brace yourself for some acronyms) and how much of each you can expect with polyphasic sleep vs the standard eight-hour monophasic sleep:

LNREM Sleep (Light Non-Rapid Eye Movement)

These first few stages of rest are also called light sleep, and during these stages your body and brain begin to slow down. While LNREM sleep is an important part of the sleep cycle, it’s the lightest stage of rest and is mostly an intermediate stage to deeper, more productive sleep.

Polyphasic sleepers try to boost their sleep density by minimizing LNREM sleep and maximizing deeper levels of sleep for the time they’re resting. In fact, average monophasic sleepers (following the standard eight hour night) can spend as much as two thirds of their sleep in just light NREM sleep.

SWS Sleep (Slow Wave Sleep)

Slow wave sleep is the third LNREM stage, although it’s much more restorative and deeper. During SWS, your brain waves slow down significantly, it’s much harder to wake up at this deep level of rest, and your body performs many of its hormonal and immune functions. And, although SWS is key to restoring your body, some sleepers require less of it than others or can function without it for longer.

REM Sleep (Rapid Eye Movement)

During REM, AKA stage four sleep, people will experience vivid dreams as their brain waves crest, and they undergo more mental and physical restoration than at any other stage of sleep. For most sleepers, regularly reaching this deepest sleep is crucial for avoiding sleep deprivation. Polyphasic sleepers try to maximize their time in REM sleep. 

Finally, although REM sleep and SWS sleep are critical to resting well, the optimal amount of time in each stage is relative to the person and their sleep pressure. For example, if you have a very high SWS sleep pressure, then your body will need more time in SWS than REM. But, if you have a high REM sleep pressure, you would need more REM sleep.

Putting all of the stages of sleep together in practice, you can expect to reach light sleep and REM sleep during a nap (18–26 minutes of sleep). Overnight, however, you can expect to reach all stages of NREM sleep, including SWS, and REM sleep too during a core sleep (30 minutes all the way up to 12 hours of sleep).

Polyphasic Sleep Science

Now that we’ve covered the basics of sleep, let’s get into how polyphasic sleep actually works. Nerdy sleep terminology aside, the main idea is that training your body to complete full cycles of sleep in shorter windows of time will also train it to be more efficient at reaching deeper sleep stages faster and staying in them longer.

This process has a name—sleep partitioning. For example, if your body is used to eight hour blocks of sleep, then it will take more time reaching deep sleep levels. Typically, this looks like 1.5 hours per stage before your body hits REM sleep. But, if you try to take a 20 minute nap, you won’t have enough time to pass the lightest levels of sleep.

On the other hand, polyphasic sleepers who’ve trained themselves to rest for shorter intervals (such as 1.5 hours) will hit stage 3 sleep soon after lying down and will spend more time in deep REM sleep. Even better, when taking the same 20 minute nap as the eight hour sleeper, the polyphasic sleeper will be able to briefly reach REM sleep.

Finally, rewiring your body to follow a polyphasic sleep pattern with sleep stability means waiting for your circadian rhythm to catch up too. Essentially, since your circadian rhythm controls your sleep, digestive system, heartbeat, blood pressure, and more—all based on the time of day—your body won’t be able to fully “power down” without it in sync. 

However, once your circadian rhythm has moved its graveyard shift (when bowel movements become hormonally suppressed for the night) to align with your new schedule, you’ll be able to more easily follow your new polyphasic schedule.

Benefits of Polyphasic Sleep

• Time: The most obvious benefit to following a polyphasic sleep schedule successfully is that it will give you back more time and without taxing your energy levels. For example, if a monophasic sleeper who followed a nine-hour schedule switched to a three-hour polyphasic sleeping routine, they would gain an additional six hours to their day, every day. Over the course of the year, this can add up to 91 additional days that would’ve otherwise been spent asleep.

• Longevity: You might believe that anything under eight hours of monophasic sleep per day causes long term health complications or leads to a shorter life. However, research indicates the opposite: individuals who sleep more than eight hours a day face health risks similar to individuals who slept only four a day. However, sleepers who rested for six to seven hours a day had the lowest death rate.

• Learning: Polyphasic sleep can be a great resource for students and fast-paced learners since a 30 minute nap can produce the same mental clarity as a full rest twice as long. So, whether working long hours or cramming for an exam, a short nap could be your best bet to rest up without losing too much time.

• Improved mood: Like learning faster, mood is deeply connected to your brain’s health. Although sleep is key to feeling good, too much sleep is linked to depression and a decreased feeling of wellbeing. On the other hand, many polyphasic sleepers report feeling an elevated mood, increased happiness, and stronger social skills.

• Dreams: Lastly, polyphasic sleepers who spent more of their naps and nights in deep REM sleep naturally experience more vivid and lucid dreams. Although lucid dreaming isn’t a necessity to have quality sleep, sleepers who actively try to lucid dream will find it significantly easier on a polyphasic sleep schedule.

Who Should Avoid Polyphasic Sleep

Risks of Polyphasic Sleeping

Because polyphasic sleeping reduces the amount of time spent in the first stages of sleep, younger poly-sleepers may lose out on the benefits of light sleep. Specifically, between stage one and stage two, sleepers experience K complexes and sleep spindles. Essentially, K complexes are larger brain waves that respond to the environment around the sleeper, and sleep spindles are shorter bursts of brainwave activity.

For younger sleepers, these K complexes and sleep spindles function by refreshing the brain’s memory and by boosting the connections between nerves and muscles. That said, some individuals with sleep disorders that prevent them from forming K complexes and sleep spindles actually face no adverse side effects.

More Risk Factors

When switching to a polyphasic sleep schedule, you should also make other lifestyle considerations including overall health, diet, and substance use. If you’re already feeling under the weather or sick, the short period of sleep deprivation that often accompanies switching sleep schedules can cause immune suppression.

Next, to maximize the benefits of a polyphasic sleep schedule with less initial fatigue, you should consider a diet with fewer refined sugars to stabilize your insulin and blood sugar levels. Ultimately, a higher quality diet leads to higher quality sleep.

Lastly, depressants and stimulants (including alcohol and coffee) both impact your quality of sleep by delaying or even preventing REM and SWS sleep.

Sleep Totals and Age

As adults age, they generally need less sleep each day to feel rested and functional. Older adults are often more resilient to instances of lower quality sleep. On the other hand, children and teenagers need up to 10 hours of monophasic sleep each day with 2 hours of REM sleep. So, younger people are at a higher risk of sleep deprivation by attempting to switch to a polyphasic sleep schedule, and, once on the schedule, will need more naps and core sleep than older adults.

Sources

Al-Abri, M., et al. (2020). Sleep Patterns and Quality in Omani Adults. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7166064/

Cleveland Clinic (2020). Sleep Basics. https://my.clevelandclinic.org/health/articles/12148-sleep-basics
Olson, E. (2018). Lack of Sleep? Can It Make You Sick? https://www.mayoclinic.org/diseases-conditions/insomnia/expert-answers/lack-of-sleep/faq-20057757

Cline, J. (2011). Sleep Spindles. https://www.psychologytoday.com/us/blog/sleepless-in-america/201104/sleep-spindles

John Hopkins University (2022). Oversleeping Bad for Your Health. https://www.hopkinsmedicine.org/health/wellness-and-prevention/oversleeping-bad-for-your-health

St. Onge, M., et al. (2016). Effects of Diet on Sleep Quality. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5015038