Keeping Fit - Rest and sleep
Rest and sleep adequate for one's personal needs are another vital component of good health and good appearance. They also influence human relationships and mental alertness. Scientists believe that during sleep the body replaces tissue cells and eliminates waste products created by fatigue at a faster rate than when awake.
Sleep also rests the heart and blood system, because heart muscle contractions and blood pressure are slower then. Excessive fatigue from lack of sleep increases susceptibility to a number of ailments, including the common cold. If an individual gets an adequate amount of sleep (usually seven to eight hours for an adult), he will feel ready to meet the day's activities. If not, his memory may not be sharp, and he may be irritable because his nervous system has had inadequate rest.
A quiet, dark, ventilated room, a fairly firm mattress, and performance of a moderate amount of exercise during the day will aid sleep. When worry, frustration, or anxiety make it difficult to sleep, a conscious attempt to relax will help. Sedatives or sleeping pills should not be taken unless they are prescribed or recommended by a physician.