There is no denying the mental health aspect of a good nap. On those days when the mind is sluggish and the body can’t seem to shift out of first gear, a few minutes of shut-eye is just the thing to breathe new life into your day. As every napper knows, however, there is a point at which a nap becomes too long, and you get up feeling even more sluggish than you were before you closed your eyes. Is there a way to determine the ideal length for a true “power nap”?
Some of history’s greatest people were unabashed nappers. Winston Churchill swore by his naps: “Nature has not intended mankind to work from eight in the morning until midnight without that refreshment of blessed oblivion which, even if it only lasts twenty minutes, is sufficient to renew all the vital forces… Don’t think you will be doing less work because you sleep during the day. That’s a foolish notion held by people who have no imaginations. You will be able to accomplish more. You get two days in one — well, at least one and a half.”
While Churchill saw 20 minutes as the ideal time, Salvador Dali, had a different technique. He slept in an armchair with a heavy metal key in his hand. He held his hand over a metal plate as he drifted off. When he slipped off into unconsciousness, the key fell from his hand banged against the plate, letting him know it was time to get up. The artist insisted he had some of his most productive moments of creativity while dozing during these brief power naps. Albert Einstein practiced a similar technique, holding a pencil or spoon to wake him before drifting too deeply into sleep.
Leonardo DaVinci claimed he needed only two hours of sleep each day. He accomplished this by taking 15-minute naps every four hours. Thomas Edison likewise operated on brief periods of sleep to recharge him for his work. The great inventor regarded sleep as the enemy of productivity, calling it a waste of time and “a heritage from our cave days.” Like Dali, he asserted that his mind was flooded with creative ideas when he was in the drowsy state leading to a power nap.
This notion was famously acclaimed by Aristotle, who wrote, “For often when one is asleep, there is something in consciousness which declares that what then presents itself is but a dream.”
While the jury is all-but-unanimous in declaring the healthful benefits of a nap, the question remains about the ideal length of time to slumber. NASA was particularly interested in the subject, given the high expectations of alertness for astronauts and test pilots. The agency sponsored a 1995 study “Alertness management: Strategic naps in operational settings,” The results were conclusive. A brief 26-minute nap for pilots resulted in alertness improvements of up to 54% and job-performance improvements by 34%, compared to pilots who didn’t nap. Napping for 40 minutes resulted in a 100% improvement in alertness.
This would not have been news to Ronald Reagan, who brushed off disparaging comments about his love of naps. He once lightheartedly told reporters that he had left instructions for his aides to wake him up in the event of a crisis, “no matter what time it is, wake me up, even if it’s in the middle of a cabinet meeting.” If napping was good enough for the Gipper, it should be good enough for you.
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