June 13, 2000 (New York) -- Get out those walking shoes. A new study shows that walking at a brisk pace for about a half hour a day can reduce a woman's risk of having a stroke. The researchers speculate that walking helps prevent stroke by lowering blood pressure, increasing levels of HDL or "good" cholesterol, and helping to maintain a healthy weight.
"Stroke is one of the major causes of death in both men and women," study author Frank B. Hu, MD, PhD, tells WebMD. "Our study suggests that physical activity can substantially reduce stroke in women."
The study, which was published in the June 14 issue of the Journal of the American Medical Association, included more than 70,000 female nurses who are part of the Nurses' Health Study, an ongoing investigation of women's health that began in 1976.
Hu and colleagues from the Harvard School of Public Health in Boston, say women in their 40s, 50s, and 60s, who walked at a moderate pace on most days of the week for at least 30 minutes, reduced by about 20% their risk of ischemic stroke -- the most common type of stroke -- which is caused by a blood clot in the brain. Those who walked at a brisk pace or very brisk pace reduced their risk about 40%.
He says the findings are important because they show that something as simple as taking a walk every day -- which just about every woman can do at any phase of her life -- can lower the risk of having a disabling stroke.
"You don't have to go to the gym [or] play sports," Hu says. "Brisk walking is not a major endeavor for most people." The walking should be enough to elevate your heart rate slightly, but not so much that you are out of breath or sweating, he says.
Another finding of the study was that even women who had been sedentary for most of their adult lives still were able to reduce their risk of stroke if they became active in their middle-age and retirement years, suggesting that the benefits of exercise are almost immediate.
Hu says women who have not been very active recently should start by walking for 10 to 20 minutes a day, several times a week and gradually increase the intensity and duration. Walking five or six days a week for about 30 minutes is ideal, but he says that women who walk less are still less likely to have a stroke than women who don't exercise at all. And walking more than 30 minutes on one or two days a week, coupled with 10- or 15-minute walks on other days, may be another way for busy women to fit exercise into their day.
Several previous investigations, including a government-sponsored panel of experts and a report from the surgeon general, concluded that there wasn't enough good data to show that exercise plays a role in preventing stroke. But an expert who reviewed the new study for WebMD says this study adds to growing evidence that exercise is an important and "natural" way to prevent stroke.
Lewis B. Morgenstern, MD, says people who have been sedentary for years should talk to their doctor and build an exercise plan that will help them achieve the goals they want in a reasonable manner and time frame.
Morgenstern, who is assistant professor of neurology and epidemiology at the University of Texas Health Science Center in Houston, says while you can't say for sure that exercise has the same effect on stroke risk in men as it does in women, it's logical to assume that it would.
"The jury is probably still out on that one," he tells WebMD. "But anything that is going to lower blood pressure and lower 'bad' cholesterol and raise 'good' cholesterol is going to be good for any person. It's likely [the results] are just as robust in men, it just hasn't been studied well enough."
- A new study shows that women who walk briskly for 30 minutes each day can lower their risk of stroke.
- Even women who have been active throughout their lives, but begin exercising in middle-age or retirement years, can reduce their risk of stroke.
- One expert recommends that inactive women should start an exercise program with 10 to 20 minutes of walking several days a week, and gradually increase intensity and time.