There was always something unacceptable about it, wasn’t there? To see someone kick back their feet and close their eyes for a brief spell seemed to hint at a deeper flaw. Why would people need to power down for twenty minutes in the middle of the day if they were making good choices at night? They must be sick. Or hungover. Or, worst of all, lazy.
But things have changed. Napping now commands the same reverence as meditation or green juice: a healthy practice that not only helps people maintain well-being, but also ups productivity and mental acuity.
And the world is becoming a napper’s paradise, with Olympic facilities, Silicon Valley managers and state universities designating conk-out zones. Soon, it seems, a trip to the nap pod will be as standard as a stroll over to the Keurig.
Napping, however, is not as simple as filling your coffee mug. Yes, there are many ways to prepare coffee but they all leave you with the same thing: caffeine. Napping is more peculiar. Lay down for too short a time and you won’t reap any of the restorative benefits; do it for too long and you’ll wake up more burnt out than before. This isn’t to say that napping is complicated. It’s more that there’s an art to it.
And that’s where this guide comes in. It contains all the information you need to make mid-day power nap work for you. Or, to borrow a phrase from psychologist James Maas, creator of the power nap, it offers everything you need to know about naps but were too tired to ask.
Let’s begin, shall we?
The Benefits of Napping
After decades of research, the evidence is clear: a short doze during the day offers short-and-long-term benefits. Brief naps (and we mean brief) can help us think clearly and concentrate more easily. And over time, the act may heal the body in surprising and significant ways, including reducing the risk of heart disease and lowering blood pressure.
James Maas is a former Cornell professor who, among other things, coined the term “power nap.” Now, as a sleep consultant for professional sports teams and high-powered corporations, Maas preaches that napping is an underutilized gift.
“Napping restores biomarkers of neuroendocrine and immune health to normal levels,” he says. “All sorts of wonderful things happen to promote better health, performance, alertness and operational settings.”
He's far from alone in his love of the mid-day lay-down. Decades of research have shown that naps can maintain or improve performance levels for the legions of bleary-eyed, sleep-deprived folks going about their days. Additionally, studies show that taking short naps before long stretches of wakefulness can have a preventative effect.
NASA has actively researched the effectiveness of napping to maintain healthy sleep habits in artificial environments. In 1994, NASA researchers followed two groups of commercial airline pilots flying between Hawaii, Japan and Los Angeles. A rest group took 40-minute naps while the planes were in cruising mode and a no-rest group stayed awake. NASA teams analyzed the pilots’ brain activity via EEG and EOG to assess their sleeping habits and alertness levels over the course of six days. The study found that a 26-minute nap improved the performance of people operating complex systems by 34 percent while improving their alertness by 54 percent.
Of course, we don’t need a study to prove napping is worthwhile. . The immediate benefits of naps are well-known to anyone who’s closed their eyes after lunch. But research also suggests napping comes with longer-term benefits A 2007 University of Athens report, which tracked more than 23,000 Greek adults over six years, found that habitual nappers were more than 30 percent less likely to die of heart disease than those who stayed awake all day. With men, that number rose to over 60 percent.
The heart-health benefits of napping may stem from its effect on blood pressure. Oddly, it may not be the nap itself that directly reduces blood pressure, as one 2007 study found that participants’ blood pressure dipped shortly before they lied down for a nap. Researchers concluded that anticipating the act of napping did the trick.
Napping also seems to act as a salve for stress. A 2015 University of Michigan study suggested that people who nap are less impulsive and handle frustration better than non-nappers.
That’s not to say naps are a cure-all. They have limits, which scientists are starting to define clearly. A 2007 NASA-funded study linked napping to improvements in some cognitive functions, but not others. Napping aided memory but not vigilance and basic alertness. As they say: all things in moderation.
The Art of the Perfect Power Nap
So how should we think about power naps? To use a metaphor, a standard night of sleep should be like a DJ set. It goes through a couple of extended grooves and builds in intensity until you reach the “drop the bass” moment of REM sleep. Then you level off before starting the cycle again, ideally to keep it going on and on until the break of dawn.
A nap is more like a pop song. It should be short, punchy and pleasant enough to get you through the day. When it’s over, you should leave wanting more. And just as hearing two Selena Gomez songs in a row can seem like a little much, an overlong nap will leave you feeling bloated and overblown.
What’s the napping sweet spot? Well, experts generally agree that the ideal power nap should last no more than 30 minutes and occur mid-day.
“Studies show that after 10 and 20 minutes the person wakes up feeling refreshed and with better concentration and better memory,” says Sanjeev Kothare, a neurology professor and and director of the Pediatric Sleep Center and Sleep Education at New York University’s Langone Medical Center.
Why? Well, that nap length enables you to soak up some energy- and performance-boosting sack-time benefits without dipping fully into deep sleep. Wake up after, say, 38 minutes and a nap has the opposite effect, making you feel sluggish rather than alert. (If you're able to squeeze it in, a full 90-minute doze is the most beneficial for memory function and creativity, as you'll wind through an entire cycle and experience that sweet, sweet deep sleep.)
“If you wake up at 40 minutes, you feel groggy because you’ve gone into slow wave sleep,” said Kothare. Same goes for more than 90 minutes: sink into a second sleep cycle and you'll suffer the consequences.
Why? Slow wave sleep (SWS), or deep sleep, is a critical part of rest, as researchers believe it’s the stage when memory consolidation takes place. But waking up from deep sleep is as jarring as hearing a needle scratch after the DJ hits the perfect groove.
More specifically, waking during deep sleep can cause what’s known as sleep inertia, a state of grogginess caused by the body remaining in in a sleep state. Under the influence of sleep inertia, you feel cloudy and may struggle to perform even simple tasks. It goes away in a half hour or less, but it renders the nap pointless.
Human sleep cycles are guided by two mechanisms: the circadian rhythm and the homeostatic drive. The circadian rhythm runs the body’s clock. It’s synced to the rise and fall of the sun for healthy sleepers through its sensitivity to light. Gradual darkness, brought on by dusk, instructs the brain to produce the sleep-inducing hormone melatonin. Unfortunately, the proliferation of artificial light has knocked many people’s circadian rhythm out of sync with the sun.
If the circadian rhythm functions like a clock, then the homeostatic drive acts like an hourglass, gradually dripping down wakefulness. After you’re awake for 15 hours, the homeostatic drive builds fatigue, making you feel sleepy. After sleep, you wake up alert and refreshed.
It’s because of these two mechanisms that naps are best when they’re short and in the middle of the day. In general the circadian rhythm causes a dip in energy in the afternoon, though timing varies among different people. The homeostatic drive puts a limit on the sleep people need; Kothare warns that long afternoon naps make it harder to sleep at night.
“Scientifically, these two drives don’t interact,” Kothare said. “But in reality, they do. Naps decrease the homeostatic drive. So if you take an afternoon nap, you’re less likely to be sleepy at 10 p.m., so you might delay or phase shift your sleep time to 11 or 12.”
To ensure you don't nap too long, you can simply set an alarm. What’s the end result effect?
“It’s nice,” Kothare said. “When you take a half-hour nap, you’re more refreshed and you will work better.”
Oh, and there’s a more extreme option, too: the caffeine nap. It works likes this: Guzzle some coffee or an energy drink immediately before a nap. Wait 20 minutes and reap the benefits of a nap lit up with rocket fuel.
“It takes about 20 minutes for the caffeine to take effect,” Maas said. “If you’re driving, for example, pull off the road in a safe area and have some coffee right before you take a nap.”
One final note: You may not be sleeping for a long time, but you shouldn’t short-change your comfort. Both Kothare and Maas recommend approaching naps them as you would nighttime sleep. Just like at night, restrictive clothing and heat warmth will keep you awake. So, dim the lights, cool the room and undo that top collar button. Work can wait.