According to the oriental concept of health care, sleep and waking up are the result of yin and yang alternation. When the yin is strong, you fall asleep, but when the yang is strong, you wake up. Therefore, Huangdi Neijing said, "When yang is exhausted, you lie down, while when yin is exhausted, you sleep." It is 1 1 in the evening to 1 in the morning, when yin flourishes and yang declines. At noon, it is 1 1 to afternoon 1, when the yang is strong and the yin is weak. From the perspective of traditional Chinese medicine, noon and noon are the time when yin and yang alternate, and also the time when the human body closes the yin and yang, which is conducive to the nourishment of yin and yang. Sleeping during these two periods is good for people's health. And the quality of sleep is the best, which can get twice the result with half the effort. Childhood is also the period when the meridians of traditional Chinese medicine run to the liver and gallbladder, so the time to nourish the liver should be deep sleep. If you miss the sleep at this time because you stay up late, your liver and gallbladder can't get enough rest, which can be manifested as rough skin, dark spots and yellow complexion. Take a nap at noon, and be "quiet" even if you can't sleep.