William Dimon, MD, founder of the Stanford University Sleep Medical Center, writes in his new book,'The Promise of Sleep': The key to falling asleep well at night is to consistently sleep at least 8 hours a day. Some people say: That's great, I usually sleep for 12 hours on weekends. However, if you only get 5 hours of sleep one night during the week, on average, your amount of sleep will still not reach the minimum standard.

Although most sleep experts agree that afternoon naps can help restore the strength of a busy morning of study and work, sporadic naps or naps cannot make up for the damage caused by long-term lack of sleep. One warning: After dozing off for half an hour, the human body will enter a deep sleep state. When you wake up, the human body will feel sluggish and lazy. Therefore, experts recommend shortening the time for dozing, napping and napping to less than half an hour.

(Editor in charge：character)