STRATEGIES: THE NAP
Unjustly maligned by Americans for too long as a sign of laziness, the nap is finally getting some respect. According to Sara C. Mednick, author of Take a Nap! Change Your Life, midday sleep can improve everything from your sex life to your learning capacity. And a 2003 Harvard study led by Mednick showed a 90-minute nap to be just as effective in helping the mind process new visual skills as a full night s sleep. Here s how to do it right.
1. Naps are not a long-term replacement for missed sleep. You need four to five consecutive cycles of sleep per night. So sleep regularly, and then take a nap if you re tired. If you re not, don t.
2. Limit yourself to one nap a day. "Anything more can mess with your nocturnal sleep," says Mednick.
3. For the ultimate nap, take a cue from the Spanish. Lie down seven hours after waking up, when you naturally become sleepy, for 90 minutes. This gives you one full sleep cycle the perfect siesta.
AMERICANS LIKE TO BRAG that they can run on six hours of sleep. Funny, because anything less than eight turns me into the type of person who will throw haymakers in the grocery checkout line. It may sound spoiled to complain about oversleeping, but for a 29-year-old runner and biker like me, the notion of having to spend one-third of my life in bed seems criminally unfair. Early this year I began to worry that I might be prone to too much sleep, so in March I paid a visit to the California Center for Sleep Disorders, an unassuming clinic in a Fremont, California, strip mall. That night I found myself lying—very much awake—in a windowless room with 15 electrodes attached to my body, straps around my chest, and a plastic cannula (a tube to monitor breathing) up my nose.
It turns out that I'm one of many people willing to go to such extremes to learn about sleep. With so many of us shorting ourselves on rest—the National Sleep Foundation reports that some 50 million of us have chronic sleep problems, and the NSF's 2008 nationwide poll shows that, on average, we get six hours and 40 minutes of shut-eye nightly—the sleep-correction industry is booming. Americans shelled out more than $3 billion for 54 million sleeping-pill prescriptions in 2007, and the number of accredited sleep clinics like the one I visited has quadrupled since 1996. The upshot of all this attention? While researchers have yet to answer the Big One—the question of why we need sleep to begin with—we understand better than ever the effects of inadequate rest. And the results go far beyond the familiar cycle of coffee in the morning and sleep aids (or Scotch) at night.
To wit: As little as 20 hours without sleep leaves you with the same impaired attention and slow reflexes of someone who is legally drunk. Chris Eatough, six-time winner of the World Solo 24 Hours of Adrenaline Championship mountain-bike race, says that during a day-long competition, his vision will occasionally stop. "I'll be flying downhill with rocks and trees to dodge," he says, "and I'll get a snapshot of the trail that doesn't change for four or five seconds."
New research also suggests that insufficient rest wreaks havoc on your emotions and intelligence. Last October, Matthew Walker, a sleep researcher at the University of California, Berkeley, found that when he showed people unpleasant images, such as attacking sharks and vipers, sleep-deprived subjects had a 60 percent stronger emotional response than well-rested ones. Sleep also appears crucial to learning and memory: Walker found in 2008 that we're about 40 percent less effective at forming new memories if we haven't had sufficient sleep beforehand. "It's not practice that makes perfect," he says. "It's practice with a night's sleep that seems to make perfect."
The list goes on: Research suggests that those who don't sleep enough have higher stress levels and an increased risk of heart attack. In 2004, researchers at the University of Chicago Medical Center found that sleep deprivation screws with the hormones tied to appetite and insulin resistance. Translation: Not sleeping can make you fat and put you at a higher risk of Type 2 diabetes.
Sounds daunting, especially since most of us don't get those elusive eight hours. (Think your Red Bull–charged system needs less? You're wrong. As you tire, your perception of what's normal changes, and you don't recognize that you're impaired.) But here's the good news: There are plenty of non-pharmaceutical methods for improving sleep—and you don't need to shove a tube up your nose to figure out what to do. (That might not help much. I slept horribly at the clinic, waking up 14 times per hour, above the normal rate of zero to five.) Set up your bedroom the right way, eat well, and exercise with the end of the day in mind and you can ditch that third cup of coffee. Your body knows how to sleep. Your job is learning how to get out of the way.