Research shows moderate to vigorous physical activity is by far the strongest predictor of an improved outcome in people who have suffered a stroke.

Vigorous walking three to five times each week decreases the chance of recurrent stroke by fivefold in patients with narrowed arteries in the brain, report investigators at the Medical University of South Carolina in an article in the journal Neurology.

The results involved patients with symptoms of intracranial stenosis, the narrowing of arteries in the brain, which is the most common cause of stroke worldwide.

The investigators analyzed three–year follow–up data for 227 patients who had been randomized to the intensive medical management arm of the MUSC–led Sammpris or stenting versus aggressive medical therapy for intracranial stenosis trial. Enrollment in the Sammpris trial, which was designed to evaluate whether stenting plus intensive medical management or intensive medical management alone was more effective at preventing recurrent stroke in these patients, was stopped early, in 2011, for safety reasons because patients in the stenting arm had a 2 ½ times higher 30–day rate of stroke or death than those in the intensive medical therapy arm.

Reaching targets for systolic blood pressure (<140 mmHg, < 130 mmHg for diabetics) and low–density lipoprotein cholesterol (<70 mg/d) significantly reduced the risk of secondary stroke, myocardial infarction or a vascular event. Approximately half of the study participants met these targets on average during the study. Those who did not were about twice as likely to experience a recurrent stroke, heart attack or vascular event.

However, moderate to vigorous physical activity was by far the strongest predictor of an improved outcome. Indeed, patients who did not regularly engage in moderate to vigorous exercise were up to five times as likely to experience a recurrent stroke or other vascular event.

How much exercise was needed to attain benefit? “At least vigorous walking for about 30 minutes, three to five times each week,” says Tanya Turan, MD, director of the MUSC Stroke Division and lead author of the article.

Study participants self–reported exercise using the 6–point Patient–Centered Assessment and Counseling for Exercise, or PACE, score. Those who scored above 3 met the target for physical activity and received benefit. Moderate exercise was defined as brisk walking or slow cycling for at least 10 minutes at a time, and vigorous activity as jogging or fast cycling for at least 20 minutes at a time.

There was evidence for a dose–dependent effect with exercise, with greater protection from vascular events seen with more exercise. All study participants were enrolled free of charge in a commercially available lifestyle modification program, which included regular coaching on healthy lifestyle behaviors.

Control of other risk factors, such as smoking, body mass index and glycated hemoglobin, did not significantly affect vascular outcomes.

This is the first report showing an association between exercise and prevention of recurrent stroke. The current American Heart guidelines for patients with intracranial stenosis recommend lowering blood pressure and cholesterol but do not mention exercise. Turan believes that, given these findings, the next version of the guidelines may be more supportive of exercise for secondary stroke prevention in patients with intracranial stenosis.

While it is true that stroke patients can have physical or emotional barriers to exercise, including stroke–related disability or depression, this analysis demonstrates that access to a lifestyle modification program can substantially increase their willingness to exercise.