One can stave off strokes by keeping even moderately fit, it seems. Yes, walking briskly half an hour a day will do, says a new study. And the findings apply to women as well as men.
Much of the previous research on stroke and fitness has been on men and relied on participants to report their physical activity, says Steven Hooker, who heads the University of South Carolina's Prevention Research Center in Columbia and led the study.
About a quarter of those in the new study were women, and everyone had a treadmill test to measure his or her fitness level.
"It seems that benefits we've been observing in men for many years ... are also observed in women and fitness is a strong predictor of stroke risk all by itself, "Hooker said, presenting his study Thursday at the International Stroke Conference in New Orleans.
In its stroke prevention guidelines, the American Stroke Association recommends at least 30 minutes of physical activity of moderate intensity on most days of the week. The new study "is certainly consistent with all of the recommendations that we already have in place," said Dr. Larry Goldstein, a spokesman for the group and director of the Stroke Center at Duke University.
Stroke is the third-leading cause of death in the US. It occurs when blood flow to the brain is stopped when a blood vessel is blocked by a clot or bursts. Hooker said physical activity could help prevent blood clots and the buildup of artery-clogging plaque.
For their research, Hooker and his colleagues used data from a study of more than 61,000 adults at the Cooper Aerobics Center in Dallas. After taking a treadmill test, the participants periodically answered health surveys. The latest research divided the group into four levels of fitness and looked at how many of them had strokes, following them an average of 18 years.
Overall, there were 692 strokes in men and 171 in women.
The study's participants were mostly white, well-educated and middle-income or higher; other populations should be studied, he said. Fitness tests were only done when people entered the study so the researchers didn't know if their fitness level changed over time.
The study found that men in the most fit group had a 40 percent lower risk of stroke than the least fit men. The most fit women had a 43 percent reduction in their risk of stroke compared with women in the least fit group.
For moderate levels of fitness, the risk reduction ranged from 15 to 30 percent for men and 23 to 57 percent in women.
The lower risks held true even when taking into account other risk factors for stroke such as smoking, weight, high blood pressure, diabetes and family history.