The afternoon nap may be a time-honored tradition in warm-weather countries, but try taking one here and the boss and co-workers will conclude you're sick, you've had a little too much vino with lunch, or you're just lazy.
Napping "is not viewed as an acceptable adult daytime activity in our culture," said Rochelle Goldberg, clinical director of the Sleep Disorders Center of the Medical College of Pennsylvania.
But new research indicates the nap may be a lot more valuable than anybody thought -- in fact, it may be a great way to catch up on lost sleep.
"There is an inherent napping tendency in all of us," said David Dinges, a biological psychologist at the University of Pennsylvania and co-author of a 1989 book, "Sleep and Alertness: Chronobiological, Behavioral and Medical Aspects of Napping."
Research on napping is opening some eyes these days, partly because of the findings of the National Commission on Sleep Disorders Research, released earlier this year. The commission found 40 million Americans suffer from chronic sleep disorders, and the consequences "span all aspects of modern society" -- and cost the country at least $15.9 billion in 1990.
"This is a very sleepy country," said June M. Fry, director of the Sleep Disorders Center of the Medical College of Pennsylvania.
Enter the nap. "It can be a way of catching up on your sleep debt," noted Ms. Goldberg.
Don't get them wrong -- every expert still says a good night's sleep is the ideal solution. But if for some reason that seven or eight hours of slumber eludes you, "it's better to take a nap than not to," said Ms. Fry.
Because afternoon napping tends to be rich in the most restful phase of slow-wave sleep, in which brain activity slows to a crawl, it's a particularly effective tool for catching up on lost slumber. Experts say a short nap in the afternoon actually leaves you "more" rested than the same amount of time tacked onto your morning sleep.
The only problem with taking a nap is that you can expect to feel groggy and disoriented for five to 15 minutes after waking up, a phenomenon known as sleep inertia. Mr. Dinges suggests giving yourself at least 15 minutes to overcome this inertia before driving, making a presentation or doing anything else that requires concentration and alertness. But then once you've overcome the inertia you'll find a bonus: "Performance improves, sometimes quite dramatically."