Power Nap - Benefits

Benefits

Power naps of less than 30 minutes—even those as brief as 6 and 10 minutes—restore wakefulness and promote performance and learning. A University of Düsseldorf study found superior memory recall once a person had reached 6 minutes of sleep, suggesting that the onset of sleep may initiate active memory processes of consolidation which—once triggered—remains effective even if sleep is terminated. A Flinders University study of individuals restricted to only five hours of sleep per night found a 10-minute nap was overall the most recuperative nap duration of various nap lengths they examined (lengths of 0 min, 5 min, 10 min, 20 min, and 30 minutes): the 5-minute nap produced few benefits in comparison with the no-nap control; the 10-minute nap produced immediate improvements in all outcome measures (including sleep latency, subjective sleepiness, fatigue, vigor, and cognitive performance), with some of these benefits maintained for as long as 155 minutes; the 20-minute nap was associated with improvements emerging 35 minutes after napping and lasting up to 125 minutes after napping; and the 30-minute nap produced a period of impaired alertness and performance immediately after napping, indicative of sleep inertia, followed by improvements lasting up to 155 minutes after the nap. Naps lasting more than 30 minutes appear to be associated with a period of impaired alertness (sleep inertia) immediately after awakening that takes some time to dissipate before wakefulness and performance improve. For several years, scientists have been investigating the benefits of napping, both the power nap and much longer sleep durations as long as 1–2 hours. Performance across a wide range of cognitive processes has been tested. Studies demonstrate that naps are as good as a night of sleep for some types of memory tasks. A NASA study led by David F. Dinges, professor at the University of Pennsylvania School of Medicine, found that naps can improve certain memory functions. In that NASA study, volunteers spent several days living on one of 18 different sleep schedules, all in a laboratory setting. To measure the effectiveness of the naps, tests probing memory, alertness, response time, and other cognitive skills were used.

The National Institute of Mental Health funded a team of doctors, led by Alan Hobson, MD, Robert Stickgold, PhD, and colleagues at Harvard University for a study which showed that a midday snooze reverses information overload. Reporting in Nature Neuroscience, Sara Mednick, PhD, Stickgold and colleagues also demonstrated that "burnout" irritation, frustration and poorer performance on a mental task can set in as a day of training wears on. This study also proved that, in some cases, napping could even boost performance to an individual's top levels. The NIMH team wrote "The bottom line is: we should stop feeling guilty about taking that 'power nap' at work."