In a world that never slows down, sleep can feel like wasted time. Polyphasic sleep promises to maximise productivity whilst cutting rest, but at what cost?

Thomas Edison once said, “Sleep is a criminal waste of time and a heritage from our cave days.” As a society, we have a conflicted (arguably toxic) relationship with sleep. We recognize how much we need it, yet it often feels like an inconvenient necessity stealing precious hours from our relentlessly busy lives. If only we could shortcut to better sleep without missing out on all its benefits. It seems the answer could be found in a polyphasic sleep schedule, which promises to do just that.

What is Polyphasic Sleep?

Dr. Mathew Weaver, a researcher from Harvard Medical School’s Sleep Division, says: “Healthy sleep would be a consolidated bout of sleep throughout the night, maybe supplemented by a nap. You’d like it to be regular and you’d like it to be high quality.” Most individuals follow a monophasic sleep schedule, sleeping for one consolidated period, typically at night. Some cultures engage more frequently in biphasic sleep, incorporating a core sleep at night with an additional nap in the afternoon. Polyphasic sleep, on the other hand, involves ‘distributing sleep around the clock’. Across a 24-hour period, an individual will engage in multiple short sleep episodes in an attempt to minimise sleep time while maximising productivity. Four popular polyphasic schedules are:

• Everyman Sleep Schedule: Involves sleeping for three hours during the night, with three 20-minute naps throughout the day, totaling four hours of sleep per 24-hour period.
• Triphasic Sleep Schedule: Divides sleep into three short periods, which take place after dusk, before dawn and in the afternoon, providing a total of four to five hours of sleep per 24-hour period.
• Uberman Sleep Schedule: Six 20-minute naps spaced evenly throughout the 24-hour day.
• Dymaxion Sleep Schedule: Consists of taking 30-minute naps every six hours, totaling only two hours of sleep per 24-hour period.

Advantages of Polyphasic Sleep:

Advocates of polyphasic sleep claim that minimising rest comes with a range of benefits, including improved sleep density and stability, improved memory retention, heightened productivity and improved learning. Famous thinkers Leanardo da Vinci and Napoleon have both credited their successes, at least in part, to versions of these routines. A polyphasic schedule has also been found to enhance lucid dreaming, a state in which an individual becomes aware they are dreaming and may even gain some control over their dream. 

The issue with these supposed benefits is that they remain largely anecdotal. Instead, a significant body of research highlights the adverse effects of polyphasic sleep compared to a standard monophasic schedule. Throughout his research, Dr. Weaver is yet to find any scientific evidence which supports these schedules, due to academic literature being sparse. “One reason for this is because these schedules are not sustainable and it’s also not a community which lends itself to evidence based research that much”, he says. Many online advocates claim that after a few weeks adjustments, the true benefits of polyphasic sleep can be experienced. Dr. Weaver argues that the only reason for this phenomenon is due to extreme sleep deprivation. “After you attempt this for two or three weeks, you’re so tired that you can initiate sleep at different times of the day. That doesn’t mean you’re successfully adapting, it means you’re pathologically sleepy.”

Disadvantages of Polyphasic Sleep:

Two issues are inherent to a polyphasic sleep schedule: acute and chronic sleep deficiency and circadian misalignment. Circadian misalignment disrupts essential biological processes, impacting immune function and hormone regulation, which over time can have long-term cardiovascular implications “Similarly chronic sleep deprivation has been associated with adverse metabolic function, depressed mood, irritability and decreased performance.” says Dr. Weaver. This layering of acute and chronic sleep deprivation means ‘there are essentially no positives’.

“We have circadian rhythms in nearly all of our cells that are driven by a transcription, translation feedback look at a molecular level”, says Dr. Weaver. These internal clocks regulate various rhythms in the body, one of the most crucial being the rhythm of wakefulness. Every 24 hours, the cycle restarts, and if aligned with our sleep schedule, allows us to experience the full benefits of restorative sleep. “Ideally, you wake in the morning and begin accumulating sleep pressure throughout the day which is opposed by a wake maintenance zone in the evening.” says Dr. Weaver. During the day, our circadian alerting signals rise to keep us awake and engaged. In the evening, these signals gradually reside, coinciding with the release of melatonin about an hour before our habitual bedtime. This allows us to have one consolidated sleep. For this ideal sleep/wake routine to take place, the clocks in all our cells must be kept at the same time. This synchronisation is managed by the suprachiasmatic nucleus, which has a ‘direct connection’ to the light we perceive in our outside environment. “So our exposure to light determines the timing of our circadian rhythms”, says Dr. Weaver.

By fragmenting sleep throughout the day, polyphasic sleep schedules work against our circadian rhythms. Instead of relying on hormones to stimulate sleep and wake, individuals rely on alarm clocks. Dr. Elizabeth Klerman, a professor of neurology at Harvard Medical School, emphasises the importance of people sleeping until they ‘spontaneously awaken’. “Using an alarm clock means you haven’t slept enough. An analogy is stopping in the washing machine in the middle of the rinse cycle. Why would you do that?” says Dr. Klerman. 

Should you try it?

“I do not recommend anyone living in today’s society to use a polyphasic sleep schedule.” says Dr. Klerman. She suggests that those considering a polyphasic schedule because they can’t set aside six to nine hours should question what obligations are preventing this. “Arranging your life to accommodate a consolidated sleep will be much better for your sleep, mood, alertness and safety”. However, for individuals with non-traditional work schedules, finding enough time for this is not always possible. Dr. Klerman says, “If you truly “can’t”, then you should aim for the longest possible nighttime sleep and then a daytime nap.” Dr. Weaver supports this approach, advocating for a biphasic schedule that includes an anchor sleep and a strong supplemental sleep. He defines an anchor sleep/core sleep as a “chunk of time that you will always be able to sleep, ideally for as long as possible.” The length of this period can differ, but should always be placed in an individual’s biological night. For a shift worker that may be during the day. This should be complemented with a strong supplemental sleep, aka a long nap. “Not everyone fits that pattern necessarily”, Dr. Weaver acknowledges. “So we do encourage people who are sleep deprived to sleep when they can. But it’s not ideal. It’s more of trying to make the best out of a bad situation than designing a desirable sleep schedule.” he says.