Taking a nap is like rebooting your brain.

It’s magical.

The Japanese even have a word for strategically sleeping on the job: “inemuri,” roughly translated to “sleeping while present.”

Pete Hamill once said, “The replenishing thing that comes with a nap — you end up with two mornings in a day.”

Sir Winston Churchill managed on just four hours sleep a night during World War Two — but insisted on a two hour nap in the afternoon.

Albert Einstein reportedly slept for 10 hours a night, plus daytime naps.

Scientists have shown that a 60- to 90-minute siesta can charge up the brain’s batteries as much as eight hours tucked up in bed.

“It’s only since the industrial revolution we have been obsessed with squeezing all our sleep into the night rather than having one or two sleeps through the day,” explains Vincent Walsh, professor of human brain research at University College London.

In one study of 23,681 Greek men over six years, the participants who napped three times per week had a 37% lower risk of dying from heart disease.

Sleep experts have found that daytime naps can improve many things: increase alertness, boost creativity, reduce stress, improve perception, stamina, motor skills and accuracy, enhance your sex life, aid in weight loss, reduce the risk of heart attack, brighten your mood and boost memory.

“Daytime naps can be one way to treat sleep deprivation. You can get incredible benefits from 15 to 20 minutes of napping. You reset the system and get a burst of alertness and increased motor performance”writes Dr. Sara Mednick in her book, Take a Nap! Change Your Life.

Napping at work is an art that is often practiced with great caution.

Sleeping on the job is one of those workplace taboos — like leaving your desk for lunch or taking an afternoon walk but it has great benefits to your brain and can improve your focus and alertness.

“Companies are suffering from tremendous productivity problems because people are stressed out” and not recovering from the workday, said Josh Bersin, principal and founder of Bersin by Deloitte.

A growing number of businesses are recognizing what research has long trumpeted: Daytime napping may come with big advantages — both psychological and professional.

In recent years, Google, NASA, Uber, Zappos and Nike all offer some form of napping benefits.

“Increasingly, companies are realizing that their employees’ health is one of the most important predictors of the company’s health, as well,” writes Arianna Huffington in her most recent book Thrive: The Third Metric to Redefining Success and Creating a Life of Well-Being, Wisdom, and Wonder.

If you are allowed to nap, or can get it right, you can genuinely improve your working life by redefining how you go about the rest of your day.

With more rest, your brain will be better at processing the glucose you get from food, giving you more mental energy throughout the day.

In a study published in Nature Neuroscience, researchers tested subjects on their performance four times throughout the day.

Performance deteriorated with each test, but subjects who took a 30-minute nap between tests stopped the deterioration in performance, and those who took a 60-minute nap even reversed it.

“Naps had the same magnitude of benefits as full nights of sleep if they had a specific quality of nap,” said Sara Mednick, a co-author of the study and associate professor of psychology at the University of California, Riverside.

How to power nap

One of the keys to power napping (also known as “cat napping” in the non-work world) is to keep them short.

Many experts say 10 to 20 minutes is the ideal duration to bolster energy and heighten alertness.

Too long a nap can risk grogginess.

The benefits of a nap can even last for several hours.

Professor Leon Lack from Flinders University explains:

Ten to 15 minutes of sleep seems to be the optimum period in terms of improving mental operations, performance, reaction times and subjective feelings of alertness. And that improvement in performance and alertness seems to be maintained for up to two and sometimes three hours after the nap. Interestingly, the five-minute nap just didn’t produce the same amount of improvement, while longer naps of 25 to 30 minutes led to subjects being somewhat drowsy and less alert for up to an hour after the nap.

A power nap is magical. It’s the most effective way to wake up and refresh your mind when you’re feeling tired and sluggish.

Moderate-duration nap taken during the usual post-lunch dip can significantly improve how you work.

The Wall Street Journal offers recommendations for planning your perfect nap, including how long to nap and when.

“For a quick boost of alertness, experts say a 10-to-20-minute power nap is adequate for getting back to work in a pinch.

“For cognitive memory processing, however, a 60-minute nap may do more good, Dr. Mednick said. Including slow-wave sleep helps with remembering facts, places and faces. The downside: some grogginess upon waking.

“Finally, the 90-minute nap will likely involve a full cycle of sleep, which aids creativity and emotional and procedural memory, such as learning how to ride a bike. Waking up after REM sleep usually means a minimal amount of sleep inertia, Dr. Mednick said.”

The National Sleep Foundation suggests that a short nap of 20 to 30 minutes is best for “short-term alertness,” providing significant benefits for improved focus without leaving you feeling groggy or interfering with sleep.

For a perfect nap, find a restful, cool, dark place to lie down in, without any noise or distraction. Or invest in a sleep mask you can keep in the office. Earplugs might help, too.

The trick, is to work out what kind of nap suits you best and stick with it if you can.

Before you go…

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Originally published at medium.com