If we calculate with 8 hours of sleep per day, one third of a person’s life is spent in sleep. Good or bad sleep is closely related to a person’s mental and physical health. There are four elements of sleep, which have a great impact on the quality of sleep. 1. sleep appliance Whether it is a bed in the south or a kang in the north, it should be placed or rebuilt in a north-south direction so that the head is north and the feet are south when people sleep, so that the organism is not disturbed by geomagnetism. The hardness of the bed should be moderate, too hard will make people have to turn over from time to time due to its stimulation, and it is difficult to sleep peacefully, and the body is sore after sleeping; the pillow height is generally appropriate to one shoulder of the sleeper (about 10 cm), too low is easy to cause cervical spine physiological bone spurs. In the summer, the pillow should often turn the sun, so as not to let the germs into the mouth and nose, lung diseases increase. 2. Sleep position People with heart disease, it is best to lie on the right side, so as not to cause heart pressure and increase the chances of morbidity; brain pain due to high blood pressure, should be properly padded pillow position; lung patients in addition to a high pillow, but also often change the side of sleep, in order to facilitate the discharge of phlegm, the stomach to see fullness and liver and gallbladder disease, to the right side of sleep is appropriate; limbs with pain, stress to avoid pressure on the pain and lying. In short, choose a comfortable, conducive to the condition of the sleeping position, help to sleep peacefully. 3. Sleep time Sleep time should generally be maintained at 7 to 8 hours, but not necessarily forced, should depend on individual differences. Those who fall asleep quickly and sleep deeply and generally have no or few dreams can fully recover their energy after 6 hours of sleep; those who fall asleep slowly and have many light sleep eyes and often have many dreams and nightmares, even if they sleep for 10 hours, it is still difficult to be refreshed, and they should go through various treatments to get effective sleep, just prolonging the sleep time is harmful to the body. Since everyone has different physiological rhythm, the arrangement of sleep morning and night should be different from person to person! In fact, different physiological rhythms make sleep appear in two ways, namely “night owl” and “lark”. This physiological rhythm is conducive to improving efficiency and quality of life, and vice versa, is not good for health. 4. The environment of sleep The sleep environment is closely related to the good and bad sleep. In the temperature of 15 to 24 degrees, you can get a peaceful sleep. Smoke left by smoking after closing the windows in winter, as well as the leakage of incomplete combustion of gas, will also make people can not sleep. In the emission of high-frequency ionizing electromagnetic radiation sources near the residence, long-term sleep and not due to their own disease, it is best to move far away from the residence. To sum up, if people can master the four elements of scientific sleep, they can effectively improve the quality of sleep and put more energy into work. Scientific sleep is the new demand of modern life for people.