BOSTON, MASSACHUSETTS. While there is considerable evidence that vigorous physical activity protects against heart disease there is much less evidence that a daily walk does likewise. Researchers at the Harvard Medical School have just released the results of a study aimed at investigating the effects of walking on heart disease risk. Their study included 73,743 postmenopausal women who were between the ages of 50 and 79 years at enrollment. During an average 3.2 years of follow-up there were 345 newly diagnosed cases of coronary heart disease, 309 strokes, and 1551 first cardiovascular events among the study participants.
The researchers found that brisk walking and vigorous exercise for at least 2.5 hours/week were equally
protective against heart disease. Both reduced the risk by about 30 per cent. This risk reduction was
independent of age, race, and body mass index and was enhanced with increasing duration and intensity of
exercise. The researchers also found that the risk of cardiovascular disease increased markedly with the
amount of time spent sitting or lying down. Women who spent 12-15 hours a day lying down or sleeping had
a 38 per cent higher risk while women who spent 16 hours or more every day sitting down had a 68 per cent
greater risk than those only sitting down for 4 hours or less. The researchers conclude that moderate intensity exercise, such as walking, confers significant
cardiovascular benefits in postmenopausal women.