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 appliances Whether the bed in the south or the kang in the north, when placed or repaired, should be north-south compliant, people sleep with their heads north and feet south, so that the body is not disturbed by the geomagnetic. 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, the posture of sleep 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 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; extremities with pain, should 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. Fast sleep and deep sleep, generally no dream or less dream, sleep for 6 hours to fully restore energy; slow sleep and shallow sleep eyes, often more dreams and nightmares, even if you sleep for 10 hours, it is still difficult to refresh the spirit, should be through a variety of treatment to get effective sleep, just prolong 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 sleep environment 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.