Break a Sweat and Bust a Stroke

Stroke risk drops for those who work out regularly and vigorously enough to break a sweat

(RxWiki News) Exercise until you sweat, and you can send your stroke risk running. Sweating during physical activity is a sign that you're getting an aerobic workout, and that can offer protection to your heart.

Many studies have shown that regular physical activity reduces the chances of having a stroke or heart disease. A new study adds to the evidence that exercise is good for heart health.

While all levels of activity may help heart health, this new study showed that moderate to intense exercise can lower the risk of stroke.

"Make exercise part of your weekly schedule."

Michelle McDonnell, PhD, lecturer in the School of Health Sciences at the International Centre for Allied Health Evidence, University of South Australia in Adelaide, and her coauthors followed 27,000 Americans for an average of 5.7 years. Participants were 45 years and older, men and women of various racial backgrounds.

One-third of the surveyed individuals reported that they were inactive (exercising less than once a week). These inactive people were 20 percent more likely to have a stroke or a mini-stroke compared with those who exercised at levels of moderate to vigorous intensity (enough to break a sweat) at least four times a week.

A mini-stroke is a temporary interruption of blood flow to the brain but not enough to destroy brain cells or cause permanent disability.

For the men in this study, moderate or vigorous intensity exercise had clear benefits. Those who engaged in this level of physical activity four or more times a week had a lowered stroke risk.

The women, however, the relationship between stroke and frequency of activity was less clear. Remarking on why this relationship between women and exercise was uncertain, Dr. McDonnell said, that women may be getting stroke-protecting benefits without vigorous exercise — through walking, for example. This focus was not part of the current research.

Participants provided details on how often they exercised but not on how long they were physically active each day.

Dr. McDonnell told dailyRx News, "For those people who perhaps have a family history of stroke, or have high blood pressure, diabetes and obesity, taking up regular exercise can reduce their risk of stroke by 20 percent."

"Not many people are aware that not being physically active is the second biggest risk factor for stroke," said Dr. McDonnell.

"The people in our study who did exercise four or more times week also had much less hypertension (high blood pressure), were less likely to be overweight or obese, and were less likely to have diabetes. So not only does physical activity improve our fitness and reduce the risk of stroke through effects on our circulation, it actually works to reduce these other risk factors for stroke, too," she said.

The American Heart Association (AHA) recommends that healthy adults (ages 18 to 65) get at least 30 minutes of moderate intensity physical activity at least five days a week, or at least 20 minutes of vigorous intensity physical activity at least three days a week. The AHA also suggests that adults should participate in muscle-strengthening activities at least two days a week, using all the major muscle groups.

Sarah Samaan, MD, cardiologist and physician partner at Baylor Heart Hospital in Plano, Texas, told dailyRx News, "It's remarkable that so many strokes could be prevented if more people just got up and exercised a few days per week. Exercise is a low-tech, low-cost intervention that can save lives, improve quality of life and cut healthcare costs."

Dr. Samaan added that no matter what a person's physical baseline may be, he or she can benefit from exercise. "If you're new to exercise, get checked out by a doctor first. It's never too late to start, but the sooner someone begins an exercise program, the more benefits he or she will reap."

The participants in this study were part of the Reasons for Geographic and Ethnic Differences in Stroke (the REGARDS) study. This study population divided relatively equally between black and white and male and female. More individuals were from the “Stroke Belt” states in the southeastern US (Alabama, Arkansas, Florida, Georgia, Louisiana, Mississippi, North Carolina, South Carolina, Tennessee and Virginia). This is an area where strokes are more common.

This study was published on July 18 in the American Heart Association journal Stroke.

The National Institute of Neurological Diseases and Stroke funded the study.

Review Date: 
July 17, 2013