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Polyphasic sleep -

Polyphasic sleep involves sleeping more than twice per day, similar to what babies do. Since the mid-1900s, people have been experimenting with polyphasic sleep to reduce time spent in bed and to seek certain health benefits.

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Many great thinkers have been linked to polyphasic sleep -

Major historical figures like Napoleon, Thomas Edison, Nikola Tesla, and Winston Churchill have been associated with unconventional and polyphasic sleeping patterns.

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Da Vinci went extreme -

Artist, inventor, and scientist Leonardo da Vinci followed an extreme form of polyphasic sleep that consisted of 20-minute naps every four hours. The unconventional sleep cycle reportedly gave him more awake time to pursue all his interests.

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The Uberman sleep cycle -

Da Vinci’s sleep cycle is now known as the Uberman sleep cycle, a strict polyphasic cycle that consists of six to eight equidistant naps across the day, each lasting 20 minutes, Men's Health reports.

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The Dymaxion schedule -

The Dymaxion sleep schedule involves taking four 30-minute naps every six hours, also equaling a total of two hours of sleep per day. It was popularized by American architect Buckminster Fuller in the 1940s, Healthline reports.

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Everyman schedule -

The Everyman schedule consists of one three-hour block of sleep per night with three 20-minute naps throughout the day. There have been many variations on the length of naps and nighttime sleep, but that's the gist.

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What’s the hype? -

Many polyphasic enthusiasts claim to experience mental and physical benefits due to polyphasic sleep, along with having more time to be productive, but there is no scientific evidence to back up any health benefits.

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It’s not all it’s cracked up to be -

Sleep deprivation is no joke! If you aren’t getting enough time asleep, you could quickly see negative effects in blood pressure, heart rate, hormones, glucose metabolism, temperature regulation, mood, and appetite.

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Is there a healthy middle ground? -

With infants and elderly people, it’s common to take naps and sleep more than just once each day, a habit which many argue we simply need to reincorporate into our busy lives.

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Enter: biphasic sleep -

Biphasic sleep refers to sleeping two times a day. It’s already common in various cultures as a sort of 'siesta' or afternoon nap. Some sleep around six hours a night and take a 20-minute nap in the day, but there are many variations on this across places like Greece, Spain, Egypt, and more.

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Ancestral biphasic sleep -

But before there was the afternoon nap, there was a long history of sleeping in two shifts with only a couple hours between them.

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Historical evidence -

In the early 1990s, psychiatrist Thomas Wehr's experiment found that people plunged in darkness for 14 hours every day for a month eventually settled into a distinct sleeping pattern of four hours, then waking up for two hours, then another four-hour sleep, BBC reports.

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Historical evidence -

In 2001, historian Roger Ekirch of Virginia Tech published a paper based on 16 years of research that revealed a wealth of historical evidence of this particular biphasic sleep, the BBC reports. His book, 'At Day's Close: Night in Times Past,' included more than 500 references to segmented sleeping across diaries, court records, medical books, and literature like Homer's 'Odyssey.' The sleep would begin around two hours after dusk, followed by a waking period of one or two hours, and then a second sleep.

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Activity between sleeps -

The waking period was often spent doing things like going to the bathroom, smoking tobacco, reading, writing, and praying. Prayer manuals were even shared in the late 15th century specifically for those in-between hours.

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There was thought it improved intimacy -

A doctor's manual from 16th-century France reportedly advised couples that the best time to conceive was "after the first sleep," as opposed to after a long day of work, because then "they have more enjoyment" and "do it better," the BBC reports.

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Helping with stress regulation -

That waking period between sleeps is thought by modern sleep psychologists to have potentially helped regulate stress naturally by enjoying an almost meditative state.

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Segmented sleep started to disappear -

Ekirch also found that references to the "first" and "second" sleep started to disappear during the late 17th century up until it totally disappeared by the 1920s.

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Infrastructure and culture changed -

Ekirch attributes the change to nighttime infrastructure, like street lighting, all-night coffee houses, and more to the way night became less a time for rest and more a time for legitimate activity.

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Artificial light launched a shift -

Whereas night used to be something dark and feared, street lamps imbued life into the late hours. In 1667, Paris became the first city in the world to light its streets, and by the end of the century many major European towns and cities were lit at night.

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People also became time-conscious -

The idea of efficiency was also simultaneously growing alongside the increasing activity of night, and when the Industrial Revolution hit, lying in bed was soon considered a waste of time.

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Trouble with monophasic sleep -

As segmented sleep disappeared, a condition called sleep maintenance insomnia took off, wherein people wake up during the night and have trouble falling back asleep. Sleep psychologists say it’s people’s anxieties of being unable to sleep the night through that actually keep them up.

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Perhaps there’s no need to worry -

"For most of evolution we slept a certain way," sleep psychologist Gregg Jacobs told the BBC. "Waking up during the night is part of normal human physiology."

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Modern problems with a historic pattern -

Timothy A. Connolly, a sleep specialist at the Center of Sleep Medicine in Houston, told Everyday Health that while biphasic sleeping worked for our ancestors, “Today, sleeping in shorter sessions is difficult, impractical, and can be destructive.”

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There isn’t enough time -

With the way many societies have structured their work hours, most people don’t have the time to sleep in two separate segments and thus would likely not end up getting enough sleep if they tried.

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Our screens inhibit us from falling back asleep -

Most people now who might wake up in the night would likely open up their phone or laptop or TV, but screens produce too much artificial light and can overstimulate your brain, making it difficult to fall back asleep.

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Whatever you do, don’t incur sleep debt -

Sleep debt is when you sleep fewer hours than your body needs, which is generally still around eight for every 24 hours. Sleep debt is cumulative and can negatively impact your health—from your immune system to your levels of focus to your memory.

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Pay back your sleep debt -

Whether it’s taking a longer monophasic sleep or taking a nap as part of a polyphasic pattern, the general consensus is that you should pay back your sleep debt as soon as you can.

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Naps can be a great solution -

Many report that biphasic sleep schedules—AKA taking naps—help them feel more alert and get more done. It’s a great opportunity to pause, recharge, and go about your day with increased focus and energy.

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Only make tweaks if you’re struggling with sleep -

So much of our daily health depends upon our sleep, so make sure that you’re talking to your physician about these changes and doing them with great care and moderation.

Sources: (Everyday Health) (Men's Health) (Healthline) (BBC) (WebMD)

See also: Out of office: Countries with the most paid vacation days per year

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