Next time your colleagues invite you on an afternoon coffee break, tell 'em you'll just take a nap instead. According to a new study by the Sleep Research Center at Loughborough University in England, a short nap may be the best way to fend off afternoon drowsiness.
The study involved 20 young adults, all of whom felt well-rested and got about seven and a half hours of sleep a night. Over the course of a week, each subject tried three different methods for battling postlunch sleepiness: sleeping in an extra 90 minutes in the mornings, taking a 20-minute nap, and consuming the equivalent of two cups of coffee in the afternoon. For the results of the study, read more.
To test each method, the researchers measured how sleepy the subjects were later in the afternoon by seeing how long it took them to fall asleep for a nap. Here's what they found:
When the volunteers did nothing, they fell asleep within nine minutes on average when tested at 3:30 in the afternoon. Sleeping late kept people awake only a minute longer on average than did doing nothing. Caffeine worked better, keeping people awake for about 12 minutes longer on average.
But nothing beat a nap. After a 20-minute nap, people nearly doubled the amount of time it took to fall asleep when tested later in the afternoon, indicating that they were no longer sleepy. None of the measures impaired people’s ability to fall asleep at night.
Isn't that just fascinating? I guess the Spanish have the right idea with their siestas. I have definitely found myself feeling refreshed after catnaps, but I never knew they were so effective. Too bad that lying down on the office couch isn't as socially acceptable as taking a coffee break. Do you think it should be?