Physical activity not only reduces the risk of stroke. Individuals who walk at least 30 minutes a day also have a lower risk of severe stroke, according to a new study in Neurology.
"It is remarkable that even light physical activity can have such a clear link to stroke outcomes," says Katharina Stibrant Sunnerhagen, professor of rehabilitation medicine at Sahlgrenska Academy at the University of Gothenburg, Sweden.
The study shows no causal relationship between exercise and protection against severe stroke, but the link is still clear. Walking four hours a week results in half the risk of a stroke becoming severe compared to those who are physically inactive. The percentage of severe strokes for the two groups is three and six percent, respectively.
"It's enough if you walk for a bit more than half an hour every day, or two 15-minute walks a day, to end up in the group with reduced risk of your stroke becoming severe," says Stibrant Sunnerhagen.
Half report having exercised
The study included 925 patients with first clinical stroke admitted to Sahlgrenska University Hospital in Gothenburg 2014-2016. The average age was 73 years at the time of becoming ill.
For the study, the researchers have combined data from two Swedish stroke registers, which indicate stroke severity based on eye, arm and facial movements, awareness level, and speech and communication abilities. Four out of five patients (79.8 percent) in the study had a mild form of stroke.
After the stroke occurrence, the patients responded to how physically active they were prior to the stroke in a standardized way. In some cases, relatives helped provide this information. Fifty-two percent indicated they had been physically inactive.
"From a scientific perspective, it is a limitation of the study that subjects self-reported their physical activity. Their memory may have been affected by the stroke, especially in those who suffered severe strokes," said Stibrant Sunnerhagen.
Light exercise is as good as moderate exercise
The subjects who indicated that they were engaged in light physical activity (walking four hours or more a week) or moderate exercise (running, swimming or similar two to three hours a week) were more likely to have mild strokes rather than severe strokes. In the study, light and moderate physical activity were equally beneficial.
Other factors such as age, gender, diabetes, and smoking also play a role. The study shows that when all known factors are considered, physical activity in combination with lower age accounts for approximately seven percent of the association withstroke severity.
In 2016, approximately 26,500 people had a stroke in Sweden. Stroke is the most common cause of permanent bodily impairment.
"Individuals having a mild stroke may stay up to a week in a hospital and can then continue their rehabilitation at home, with good potential to return to their normal life and work. After a severe stroke, hospitalization is much longer and sometimes followed by care at a nursing home," says Stibrant Sunnerhagen.