Nap Time

Recently, however, sleep scientists have discovered advantages to napping, which they view not just as solace but also as something akin to brain food. No longer written off as a cop-out for the weak and the bored, the nap is coming into its own as an element of a healthy life.

Some new studies make dramatic claims for it. Taken in the workplace, naps can increase productivity and reduce 8220;general crabbiness8221; according to a just-concluded 25-year survey of the practice in industrial countries.

A study conducted by researchers at the University of Haifa in Israel showed daytime nappers doing better at retaining a newly mastered skill 8212; bringing a thumb and forefinger together in a certain sequence 8212; than a control group whose members slept only at night.

Experiments conducted by Matthew A Tucker of Harvard Medical School suggest that a 45-minute nap can enhance the ability to perform tasks relying upon memory. And Dimitrios Trichopoulos, also at Harvard, has found that among a sample of 23,000 adult Greeks, habitual nappers were 30 per cent less likely to die of heart disease.

When you take a look at American history, we might seem a nap-friendly people. After all, some of our most productive figures napped shamelessly during the day, among them Benjamin Franklin and Thomas Edison. But they probably did so because they couldn8217;t help it.

Consider the daily schedule Franklin drew up for The Art of Virtue, a treatise he worked on for 50 years but never finished: Over a 24-hour period, sleep gets allotted a mere five hours. Or take the contemptuous words of Edison: 8220;Sleep is an acquired habit. Cells don8217;t sleep. Fish swim in the water all night. Even a horse doesn8217;t sleep. A man doesn8217;t need any sleep.8221;

For these Type A personalities, napping may have been a badge of honor, proof that they disdained sleep as a nuisance to be beggared and cheated. By the way, Edison may have known a lot about filaments and wires, but he was dead wrong about fish and horses.

Napping was more valued on the other side of the Atlantic, where the habit8217;s foremost champion was probably Winston Churchill.

In The Gathering Storm, the first volume of his World War II memoirs, the British statesman wrote, 8220;Nature had not intended mankind to work from 8 in the morning until midnight without the refreshment of blessed oblivion which, even if it only lasts 20 minutes, is sufficient to renew all the vital forces.8221;

In southern Europe, naps were woven into the fabric of life. But Spain, where the siesta is deeply ingrained, has been adjusting to changed circumstances 8212; in 2005, the Spanish government cancelled the siesta for its employees.

But the recent experiments, along with a relaxation of the old 9-to-5 rigidity, have awakened employers to the benefits of on-the-job sleep. A growing number of companies either make nap rooms available to their employees or encourage them to put their heads down on their desks. High-tech firms with a youthful workforce tend to be cooler with on-the-job snoozing than old-line companies staffed mainly by veterans 8212; a contrast that shows up at The Post. The paper8217;s headquarters in downtown Washington lacks a room dedicated to naps, whereas the company8217;s Internet operation in Arlington has a small one set aside for that purpose.

According to information collected by the National Sleep Foundation, Toyota encourages naps at its Tokyo headquarters, where they are easy to take thanks to an energy-conservation policy: During lunch hour, the company turns off its lights.

In New York, those who can8217;t find the peace and quiet they need to nap at work can patronize Yelo, a Manhattan sleep salon.

All this should please Sara Mednick, perhaps napping8217;s most ardent advocate among the US scientists: She8217;s so sold on the practice that she calls a napless existence 8220;the madness of monophasic sleep.8221;

Mednick brings to her discipline impressive credentials 8212; she is a professor in the psychiatry department at the University of California at San Diego.

Last month, Mednick was in Washington to give a talk at the Role of Sleep in Memory and Learning Conference, a co-production of the National Sleep Foundation and the Atlanta School of Medicine. She used slides and cited studies, but above all she projected enthusiasm for her favourite practice.

8220;A perfect nap in the middle of the day,8221; she declared, 8220;is like a mini-night.8221;

But while napping may be advisable for most people, a tricky question remains: How long should the interlude be? With naps, as with so much else in life, can you have too much of a good thing?

Another expert at the conference, Eric Nofzinger of Harvard, drew the line: 8220;The more you keep insomnia patients awake during the day, the more consolidated sleep they8217;ll get at night.8221;

Fair enough. Severely troubled sleepers should consult a physician about fixing their slumber, perhaps with naps of suitable length folded in. Those with less dire problems can use trial-and-error to determine what napping coordinates work best for them.

As for the lucky rest of you, you8217;re free 8212; and encouraged 8212; to nap for as long as 90 minutes per day. Beyond that, almost everyone runs the risk of encroaching on nighttime sleep.