I never used to nap. Even as a child I resisted sleep in all of its forms—especially the daytime variety. Strangely enough, screaming "I'm not tired!" never seemed to convince my parents that I didn't need to hit the hay. So I would just curl up in bed, counting the flowers on the wallpaper until it was time to get up and play again.

As an adult, I continued my strike against daytime slumber, even though as I got older I rarely managed a full eight hours of sleep. I decided that there was no such thing as a perfect night's rest. After all, my mother was a nurse who worked nights, and she rarely got more than four or five hours of shut-eye. I would just do without—and forget about napping. "Napping will just make me feel more tired when I wake up," I insisted. So I continued in my zombie daze, feeling irritable and guzzling coffee to make it through the afternoon.

Eventually I realized I wasn't as productive and alert as I thought I was. I did some research and found that for most adults, seven to eight hours a night seems to be the best amount of sleep. A fully rested night is called "recovery sleep," and it pays off the "sleep debt" that people like me incur by spending too many wakeful hours staring at the ceiling.

Of course, many people don't get a full eight hours. According to a recent report from the Centers for Disease Control, approximately 41 million people in the United States—nearly one-third of all working adults—get six or fewer hours of sleep a night.

Could napping help bridge the gap? The answer is yes. NASA conducted several studies that demonstrated that naps can, in fact, restore alertness, enhance performance, and reduce mistakes and accidents.

Astronauts and alertness

One study, which focused on sleepy military pilots and astronauts, showed that a 40-minute nap improved performance by 34 percent—and alertness got a 100 percent boost. "We found that when pilots get a nap, they maintain consistent performance," said Dr. Mark Rosekind, team leader of the Ames Fatigue Countermeasures Program. "Their performance was the same during the day and at night. Their performance also was the same at the end of the flight and after multiple flights."

However, in another report, NASA scientists found that naps are a short-term fix, offering only temporary boosts in mental acuity. "They cannot replace adequate recovery sleep over many days," says David Dinges, a professor at the University of Pennsylvania School of Medicine. In other words, even though there's no substitute for eight hours of shut-eye a night, naps can help you feel better, sharper and more refreshed in the short term.

Power-napping tips

If you're not getting a full night's sleep, a daytime nap might be just the thing to help you make a small down payment on your sleep debt. According to the National Sleep Foundation, there are some keys to successful napping:

  • Take a short nap of 20 to 30 minutes at a time. Sleeping for too long will make you feel groggy and interfere with your next night's rest.
  • Find a quiet, comfortable spot with low lighting. But stay out of bed, since you associate your bedroom with long periods of rest.
  • Time your nap to happen right in the middle of your wakeful day. Be sure it's at least five hours before you plan on going to sleep that night (between 2 p.m. and 4 p.m. is prime).

And don't stress out if you're not falling asleep—some studies have shown that just spending time resting can be beneficial. So if you find yourself in a dry spell, and you're not getting the full night of sleep you need to stay alert, consider trying a short snooze.

I've come a long way from the tearful child who hated nap time. In fact, one of my favorite things to do on a rainy Sunday afternoon is to curl up on the couch with a blanket for a half hour. If you think you're too old (or too young) for a daytime doze, think again! After all, getting enough sleep on regular basis—regardless of when you get it—is the best way to stay healthy and feel your best.

Lisa Cannon

Lisa Cannon has been a writer and editor for nearly 20 years. She writes about everything from the health benefits of journal writing to the best ways to recycle computer hardware. She lives in beautiful Portland, Oregon.