Power Napping is good for you.

How Long Is A Good Nap?
THE NANO-NAP: 10 to 20 seconds Sleep studies haven’t yet concluded whether there are benefits to these brief intervals, like when you nod off on someone’s shoulder on the train.
THE MICRO-NAP: two to five minutes Shown to be surprisingly effective at shedding sleepiness.
THE MINI-NAP: five to 20 minutes Increases alertness, stamina, motor learning, and motor performance.
THE ORIGINAL POWER NAP: 20 minutes Includes the benefits of the micro and the mini, but additionally improves muscle memory and clears the brain of useless built-up information, which helps with long-term memory (remembering facts, events, and names).
THE LAZY MAN’S NAP: 50 to 90 minutes Includes slow-wave plus REM sleep; good for improving perceptual processing; also when the system is flooded with human growth hormone, great for repairing bones and muscles.

1. The first consideration is psychological: Recognize that you’re not being lazy; napping will make you more productive and more alert after you wake up.
2. Try to nap in the morning or just after lunch; human circadian rhythms make late afternoons a more likely time to fall into deep (slow-wave) sleep, which will leave you groggy.
3. Avoid consuming large quantities of caffeine as well as foods that are heavy in fat and sugar, which meddle with a person’s ability to fall asleep.
4. Instead, in the hour or two before your nap time, eat foods high in calcium and protein, which promote sleep.
5. Find a clean, quiet place where passersby and phones won’t disturb you.
6. Try to darken your nap zone, or wear an eyeshade. Darkness stimulates melatonin, the sleep- inducing hormone.
7. Remember that body temperature drops when you fall asleep. Raise the room temperature or use a blanket.
8. Once you are relaxed and in position to fall asleep, set your alarm for the desired duration (see below).