Medical researchers at Harvard and Standford Universities who studied the habits and health of 17,000 middle-aged and older men, reported the first scientific evidence that even modest exercise helps prolong life. Dr. Ralph S. Paffenberger, the visiting professor of epidemology at the Harvard School of Pubic Health, who is the principal author of the report said, " We have found a direct relationship between the level of physical activity and the length of life in the college men we have studied. " He added," This is the first good evidence that people who are active and fit have a longer life span than those who are not. "

A strong connection between a hard and a healthy hard has also been convincingly demonstrated in the same study. The study showed that the less active persons ran a three times higher risk of suffering a fatal heart attack than did those who worked the hardest. Review of fatal heart attacks revealed that the less active men were also three times more likely to die unexpectedly and rapidly within an hour after the attack.

A parallel research report from doctors in Dulles also concluded, after a study of the lives and habits of 6,000 men and women, that the physically fit were less likely to develop hypertension. Dr. Steven N. Blair who headed the research group said, " We followed the physical health and habits of these people for an average of four-and-a-half years and the data showed that the lackof physical fitness leads to hypertension. "

Exercise increases calorie output. The body fat can be reduced by regular exercise. It is therefore, useful for weight reduction in conjunction with restricted food intake. According to a study by Dr. Peter Wood of Stanford University Medical School, author of ' California Diet and Exercise Programme ', very active people eat about 600 more calories daily than their sedentary counterparts but weight about 20 per cent less. Upto 15 hours after vigorous exercise, the body continues to burn calories at a higher rate than it would have without exercise. Moderate physical exercise has been found to be accompanied by less obesity and lower cholesterol levels.
Regular exercise plays an important role in the fight against stress. It provides recreation and mental relaxation besides keeping the body physically and mentally fit. It is nature's best tranquilliser.

Chronic fatigue caused by poor circulation can be remedied by undertaking some exercise on a daily basis. It helps relieve tension and induces sleep. Moderate physical exercise at the end of a try day can bring a degree of freshness and renewed energy.

Exercise also plays an important role in the treatment of depression. According to Dr. Robert Brown, a clinical associate professor at the University of Virgina School of Medicine, " Exercise produces chemical and psychological changes that improves your mental health. It changes the levels of hormones in blood and may elevate your beta-endorphins (mood-affecting brain chemicals). Exercise also gives a feeling of accomplishment and thereby reduces the sense of helplessness. "