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Walking Reduces Stroke Risk in Women

What the Study Showed
How it was Done
Why It's Important

What the Study Showed
Regular exercise, such as moderately brisk walking, can dramatically lower the risk of stroke in middle-aged women, according to this large study published in the June 2000 issue of the Journal of the American Medical Association. Women who walked regularly and at a fast pace cut their risk of stroke--the kind caused by blocked blood vessels--by more than a third.

How it was Done
Information from more than 72,000 female nurses, all participants in the on-going Nurses' Health Study, was used in this investigation. Beginning in 1986 and twice over the following eight years, the nurses filled out health and exercise questionnaires that detailed the amount of time they spent each week doing physical activities, such as walking, jogging, running, and cycling.

Walking was considered an activity of "moderate" exertion overall, although the questionnaire did make a distinction between "brisk" (3 to 3.9 mph) and "very brisk" (4 mph) walking. Activities considered "vigorous" included jogging, biking, squash, and tennis.

All the participants were free of heart disease or cancer when the study started.

Why It's Important
Walking is the most popular form of moderate-intensity exercise among American women between 40 and 65 years old, the age group studied here. And apparently for good reason: Study after study has shown that increased physical activity, even a low-impact exercise such as walking, substantially lowers the risk for coronary heart disease.

Now, with the findings of this large JAMA study, there's evidence to show that moderate-intensity exercise (such as walking) can substantially reduce the risk of stroke, a common and often devastating cause of disability and death. The link was notable primarily for ischemic stroke, the type associated with clogged blood vessels.

Women who spent at least 7 hours a week engaged in moderate-to-vigorous physical activity cut their risk of stroke (primarily ischemic stroke) by 40%. Put another way, for every increase of 3.5 hours a week in moderate to vigorous physical activity, there was a 19% reduction in stroke risk among study participants.

While it didn't matter how many hours a woman walked, it did matter how fast she went. The quicker the pace, the greater risk reduction she reaped. Participants with a brisk-to-very brisk pace cut their risk of stroke by 51%, compared to 19% for those who walked at a more moderate rate.

Bottom line: If comparable calories were burned, vigorous physical activity and walking produced similar reductions in stroke risk.

It's probable that exercise lowers stroke risk by reducing blood pressure, boosting HDL ("good") cholesterol levels, lessening the risk of blood clots, aiding weight loss, and enhancing insulin sensitivity.

Source: Hu FB, et al. Physical activity and risk of stroke in women. JAMA 2000;283:2961-2967

Date Published: 02/19/2001
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