Five Good Reasons to Get 40 Winks

1. The recuperative effects of an afternoon nap can more than make up for the loss of an hour of nighttime sleep.


2. Multiple naps can lessen the impact of subsequent sleep deprivation. For example, an M.D. would perform far better if she were to take a few naps before going on call for 48 hours.


3. Even a 15-minute rest can improve your alertness, performance and mood for hours.


4. Naps, not caffeine, can help prevent motor-vehicle accidents caused by sleep deprivation. A tired driver who drinks coffee to stay awake is still likely to succumb to "micro sleeps"–brief naps lasting four or five seconds. In that short time, a car going 55 miles per hour may travel more than 100 yards, which can easily cause a fatal accident.


5. You'll be able to work longer. Research on transoceanic sailors in the Around Alone race–which takes place every four years–showed that by taking frequent naps, the sailors could function for days at a time with only three hours of sleep in each 24-hour period. (The inventor Thomas Alva Edison was famous for catnapping in his office to help him work through the night.)

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