Power napping can improve your performance at work, but it may depend on the length of the nap.
A nap between 45 minutes and 60 minutes can result in an increase in information retrieval, according to a study by researchers at Saarland University in Germany published in the journal Neurobiology of Learning and Memory.
Participants were asked to learn 90 single words and 120 word pairs that were effectively meaningless or made no sense to exclude the likelihood that they could be familiar with the word pairs. People who had napped retrieved five times more information than people who watched movies. However, naps didn't improve “associative memory,” the ability to recover a memory associated with a place or event. Speaking of the part of the brain that plays a major role in both short- and long-term memory, the researchers wrote: “These results speak for a selective beneficial impact of naps on hippocampus-dependent memories.”
While many studies show that a night of sleep of up to eight hours can help people perform better at tasks during the day, other studies recommend shorter nap times. Some people can suffer from “sleep inertia,” meaning their body entered a deep sleep and, therefore, it takes them longer to wake up from a nap, studies have shown. By comparing the recall of a list of 30 words after a group of people experienced no napping, short napping and long napping, there was superior recall for both nap conditions in contrast to those who remained awake, a 2008 study in the Journal of Sleep Research concluded. “These results demonstrate that even an ultra-short period of sleep is sufficient to enhance memory processing,” the study found.
James Maas, former chairman of the Department of Psychology at Cornell University who is widely credited with coining the term “power nap,” says people should choose between 20 and 90 minutes for a power nap, should set an alarm, only nap if they haven’t had adequate sleep (7.5 hours or more), sleep in a space heated at 65 to 68 degrees Fahrenheit, and rest laying down. People often overestimate the sleep they actually get, “often by 45 minutes,” he says. Research has found that there is a significant correlation between lack of sleep and stress, depression, ability to think and perform, hypertension, heart attacks, strokes, Type II diabetes, periodontal disease, skin problems, obesity and even cancer, Maas says.
Sleeplessness at work is a big problem, studies show. Nearly a quarter of all workers are affected by chronic sleeplessness, according to a 2011 study by Harvard Medical School, and at least 10 percent of Americans say they are likely to fall asleep at their desk, during a meeting or commuting to or from work, according to a 2012 survey by the National Sleep Foundation. And insomnia costs an average of $2,280 per worker in reduced productivity every year — a total cost of $63.2 billion to the economy, the Harvard study found, which equates to 11 working days lost annually for each worker. In high-risk professions, dozing off at work can even put lives at risk.
While some companies like Google Inc. have nap rooms for employees, catching 40 winks for many workers isn't easy or acceptable during a busy day. “Napping is looked down upon in many companies,” says Dan Schawbel, founder of WorkplaceTrends.com. He says it is more acceptable in the laid-back culture of Silicon Valley than the heady world of New York finance, and less acceptable in industries that deal directly with customers. “Older generations in particular want to see younger employees pay their dues,” he adds. “You’ll see napping more in startups, technology companies and employers wanting to recruit younger people.”
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