Women who exercise just half the amount recommended by the National Institutes of Health (NIH)?currently set at 30 minutes a day or more most days of the week?experience significant improvement in fitness. That’s what a group of U.S. researchers found when they studied 427 previously inactive postmenopausal women for six months and had them take part in one of four programs of physical activity.
One group exercised half the amount NIH recommends, another group followed the NIH recommendations to a ?T? and a third group exercised 50% more than recommended. A fourth group didn’t change its sedentary habits.
The researchers found that fitness improved incrementally as physical activity increased. While more was better, the findings suggest that even an hour and 15 minutes of moderately intense physical activity each week can have an important impact on fitness.
Journal of the American Medical Association, May 16, 2007.