Sleep experts don't call it a "power" nap for nothing. Napping can help boost productiveness, reduce the potential for accidents, relieve stress and de-grump overworked employees.
"The benefits of napping are widely researched and scientifically validated," according to Dr Gregg Jacobs, author of Say Good Night To Insomnia. "We hope the time will come when it's routine during the workday to take a 20minute nap instead of a 20-minute coffee break."
US President George W Bush recently told reporters, "I'll answer some questions and then I'm going to head home and take a nap." Former US President Bill Clinton once said: "Every major error I made in my life . . . I made when I was tired." (Well, almost every major error.)
Napoleon napped. Churchill napped. Einstein, too. So did Thomas Edison, whose invention of the light bulb in 1879 is frequently seen as the primary cause of our sleep-deprived lives.
Ellen MacArthur who, at 24, is the youngest woman to have taken part in the 26,000-mile Vendee Globe solo round-the-world yacht race, put her success in coming second in that race down to power napping. The British yachtswoman takes regular 15minute naps while sailing, enabling her to average five hours sleep per night. If your hectic lifestyle, on or off the high seas, means you're missing sleep, sleep experts say regular napping will help.
Research indicates the body is designed to rest in the middle of the day - with or without a large lunch. Our natural sleep pattern is biphasic: that is, we experience a drop in our core body temperature and alertness at night, and a similar, but smaller, drop during the afternoon. When we are tired and over-worked, we deplete our adrenal glands - two thumb-sized endocrine organs at the top of our kidneys that are crucial in maintaining energy levels.
While napping is not bad, you should still ask yourself why you feel the need, advises Dr Catherine Crowe, who works at the sleep disorder clinic at Dublin's Mater Private Clinic. "If you have a long commute, it is a good idea to nap on the train. If you are napping because you are going out drinking every night, obviously it is not so good." Napping may also be linked to sleep deprivation, excessive working hours, insomnia or some other sleep disorder.
You may or may not, therefore, be able to address the cause. Older people, for instance, will have a greater propensity to nap, but if you are persistently sleepy, Dr Crowe advises people to discuss it with their doctor. "It shouldn't be more than a yawny feeling," she says. "The Spanish may take an hour-long siesta in the middle of the day, but they may also sleep one hour less at night. There's a normal propensity for alertness to wane just after lunch."
But naps differ from siestas. If you nap for more than 30 minutes, your body may lapse into delta (or deep) sleep, causing grogginess. "If you're sleep deprived and must nap longer than 30 minutes you should probably extend it to an hour and a half to complete the sleep cycle," says Dr James Maas, author of Power Sleep and psychology professor at New York's Cornell University. "But don't expect to be fully alert until at least an hour after the nap."
Irregular napping is not advisable. It may disrupt your circadian rhythms - your 24-hour internal body clock. Nor, contrary to popular belief, will coffee help. Too much caffeine may be followed by lethargy and can reduce the quality of your sleep that night, Dr Maas adds. "Sleepy workers are irritable, likely to make mistakes and cause accidents, and are more susceptible to heart attacks and gastrointestinal disorders," he says. "That costs money and disrupts lives."
Ciaran O'Boyle, professor of psychology at the Royal College of Surgeons in Dublin, is in favour of relaxation and/or napping rooms to improve the quality of working life, but he cautions against the headline-grabbing effect such a move might have. Sleep rooms should be part of a larger policy aimed at reducing stress. "It might create an image when it's just window dressing," he says. "When you look at other policies, empowerment may be just skin deep."
In the workplace, individual strategies to reduce stress aren't effective in isolation, O'Boyle says. "The most important strategy is organisational change or development. If you are under resourced at work and have a bad boss, there is not a lot of sense in teaching employees to learn yoga or giving them a power napping room." He is also an advocate of employee assistance programmes which can provide counselling services.
US employers tend to be more progressive. Tom DeLuca bills himself as "the man who's putting corporate America to sleep" on his website www.powernap.com. He carries out workshops across the US aimed at improving employee performance. "There is a direct correlation between energy and efficiency. Obviously, capability is necessary as well.
"Even if you are an expert in your field, if your mind and body are exhausted, you're not able to perform as well."
Some US companies have established sleep rooms, while some airlines allow pilots to take naps on long-haul flights after a NASA-led study showed that naps can improve pilot performance. "The power nap is designed to help your mind and body to recharge," says DeLuca. Whether it's at your desk during lunch or on a train before work, it can help you to concentrate, prioritise and work more efficiently.
We encourage children to power nap, yet why do we not afford ourselves the same privilege? Children nap for different reasons, DeLuca says. They need more sleep as they grow, whereas adults need to restore their mental energy. While children take 40 winks, adults have fallen into work patterns that rob us of sleep, including longer working hours, erratic eating patterns, raising children and, DeLuca says, "using our beds as an extension of our desk".
But remember, napping too late in the day will disrupt your night time sleep. Most experts agree that early to mid-afternoon is the best time to take a nap at work, especially if you have a long drive home. But, as napping is still taboo, you may want to close the office door.
"It's frowned upon," says Dr Catherine Crowe. "It's seen as moral weakness, which is unfair. Look at the bad guy in children's stories. He's always asleep with a big fat tummy."
