To elucidate whether physical activity is protective against first stroke among older persons, Joshua Z. Willey, from Columbia University Medical Center (New York, USA), and colleagues studied 3,298 men and women, average age 69 years, enrolled in the Northern Manhattan Study, a prospective cohort study of older, urban-dwelling, multiethnic, stroke-free individuals.  Following the subjects for 9 years, tracking the incidence of strokes and monitoring physical activity, the researchers found that those men who participated in moderate-to-heavy intensity activities, such as jogging, playing tennis, or swimming, were 63% less likely to have a stroke, as compared to people with no physical activity. The baseline risk of ischemic stroke over five years was also markedly reduced among those engaging in moderate-to-heavy intensity activities, standing at 2.7% (among the entire group, the risk was 4.3%, and among those with no activity it was 4.6%).  The team concludes that: “Moderate- to heavy-intensity physical activity … is protective against risk of ischemic stroke. Engaging in moderate to heavy physical activities may be an important component of primary prevention strategies aimed at reducing stroke risk.”