People who participate in vigorous activity are less likely to experience so-called "silent" strokees, new study findings report Specifically, older adults who got the most exercise - equivalent to swimming or biking more than once per week - were 40 percent less likely to experience a silent stroke, in which brain scans show a stroke occurred, but they experienced no symptoms.
Even though these strokes are "silent," people who experience them are more at risk of other problems in the future, such as trouble with walking or mental functioning, as well as typical strokes, explained study author Dr Joshua Willey at Columbia University.
He and his colleagues found that people who engaged in less vigorous exercise - perhaps doing vigorous activity less frequently, or sticking with low-impact exercise such as golfing or bowling - were no less likely to experience silent strokes. The study doesn't prove whether physical activity actually prevents stroke. People who participate in such activity may have other habits, or characteristics, that lower their risks.
Still, exercise is helpful for other reasons, Willey said. "We know that light to moderate exercise helps with many other conditions. And we don't want our results to discourage our patients from doing exercise. Any is better than none, just in general, for overall health," Willey told Reuters Health. "And it seems to be, the more the better."
The study included older adults, many of whom can continue to play tennis, swim, bike, and do other types of vigorous exercise, he said. But before starting a program, it's important to consult your regular doctor or cardiologist, to ensure it's safe, Willey cautioned. Vigorous activity "can be safe once cleared."
During the study, Willey and his team at Columbia and the University of Miami interviewed more than 1,200 people 55 and older who had no symptoms of stroke and were already participating in a study on the risk of stroke about physical activity, then performed brain scans to check for "silent" strokes.
Among the participants, who averaged 70 years of age at the time of their brain scan, 16 percent had experienced a silent stroke, known as silent brain infarcts. Only those who engaged in the most activity had a reduced risk, the authors note in the journal Neurology. It was somewhat surprising to see that people who engaged in less vigorous forms of exercise were not protected from silent strokes, said Willey.
"That throws us off a little bit." Previous studies have also shown, however, that only moderate or heavy exercise appears to ward off stroke, he noted. In addition, only 36 percent of participants engaged in light exercise, and this may not be enough people to reveal a true impact, Willey added.