People who walk just 35 minutes a day or participate in light to moderate physical activity, such as swimming two to three hours a week, may have less severe strokes than people who are physically inactive.

In a new study, to determine physical activity, participants were asked after the stroke how much they moved or exercised during leisure time before the stroke. Questions about duration and intensity of exercise were used to determine the average amount of physical activity. Relatives were asked to confirm exercise levels when needed.

Study author Katharina S. Sunnerhagen, said, "Stroke is a major cause of serious disability, so finding ways to prevent stroke or reduce the disability caused by stroke are important. While exercise benefits health in many ways, our research suggests that even simply getting in a small amount of physical activity each week may have a big impact later by possibly reducing the severity of a stroke."

Light physical activity was defined as walking at least four hours a week. Moderate physical activity was defined as a more intense exercise such as swimming, brisk walking, or running two to three hours a week. Of study participants, 52 percent said they were physically inactive before having their stroke.

Researchers found that people who engaged in light to moderate physical activity before their stroke were twice as likely to have a mild stroke rather than a moderate or severe stroke when compared to people who were physically inactive.

Sunnerhagen added, "There is a growing body of evidence that physical activity may have a protective effect on the brain and our research adds to that evidence. Further research is needed to better understand just how physical activity influences the severity of a stroke."

Sunnerhagen noted that the difference in physical activity did not account for a large amount of the difference in stroke severity. When combined with younger age, greater physical activity accounted for only 6.8 percent of the difference between the two groups. The full study is present in the journal- Neurology.