The best time to take a nap should be chosen about half an hour after lunch, and sleep for 20-30 minutes is appropriate, so that the brain can get a good rest, and the performance of the afternoon will be extra improved. If the sleep time is too long, it is easy to enter deep sleep, but also stir up the biological clock, but will affect the night sleep, which must be noted. For the people who are more easily fatigued after the nap instead, it is recommended to shorten the time of the nap appropriately so that the nap has not entered the short-wave sleep stage. Because people in the short-wave sleep stage, relatively difficult to wake up, the nap time is too long, wake up will also be very uncomfortable. So how long to nap or according to the combination of personal habits, time to nap after a clear head, body relief, full of spirit shall prevail, it is best to rest for about 20 minutes after lunch and then sleep.