There's an art to napping.

Studies have found different benefits—and detriments—to a nap's timing, duration and even effect on different people, depending on one's age and possibly genetics.

"Naps are actually more complicated than we realize," said David Dinges, a sleep scientist at the University of Pennsylvania's Perelman School of Medicine. "You have to be deliberative about when you're going to nap, how long you're going to nap and if you're trying to use the nap relative to work or what you have coming up."

A snooze on the couch on a Sunday afternoon may seem like the perfect way for a responsible adult to unplug. But at a time when roughly one-third of people report not getting enough sleep, more naps, albeit short ones, might make for a more functional workforce, researchers say.

Sleep experts break sleep down into several stages, which the brain cycles through roughly every 90 to 120 minutes. These stages are broadly characterized into non-rapid eye movement (NREM) sleep and rapid eye movement (REM) sleep. NREM is further broken down into stage one and two, which are considered light and intermediate sleep, followed by slow-wave sleep. Awakening from slow-wave sleep, the deepest kind, results in what doctors call sleep inertia or sleep drunkenness: that groggy feeling that can take awhile to shake off. Finally, there's REM sleep, often associated with dreaming.