In individuals with stroke or TIA who sit for long periods of uninterrupted time during the day, it may be reasonable to recommend breaking up sedentary time with intervals as short as 3 minutes of standing or light exer- cise every 30 minutes for their cardiovascular Synopsis Regular physical activity reduces stroke risk116 118 ; posi- tively affects stroke risk factors, for example, BP, cho- ; and can improve endothelial function and reduce platelet aggregation, fibrinogen lev- and onset stroke severity.123 Physical inactiv- ity (eg, sitting >4 h/d) as a cardiovascular risk behavior124 is attenuated by increased bouts of moderate- to vigor- ous-intensity physical activity.125 Low levels of physical activity are observed in acute,126 subacute, and chronic phases of stroke, with >78% of recorded time catego- rized as sedentary.127 When able, stroke survivors should aim to achieve population-based recommendations (40-minute sessions, 3 to 4 times per week of moderate- to vigorous-intensity aerobic activity),26 and when this is not possible, their physical activity goals need to be cus- tomized to their exercise tolerance, stage of recovery, environment, available social support, physical activity preferences, and specific impairments, activity limitations, and participation restrictions as identified by the AHA/ ASA guideline for physical activity and exercise.34 Exercise interventions positively affect disability, aerobic fitness, mobility (walking speed), and functional balance indices after stroke.128 Efficacy of exercise inter- ventions compared with usual care was established by a meta-analysis for risk factors after stroke, including BP, cholesterol, glucose levels, and weight.112,113 Physical activity interventions are often delivered in multimodal, lifestyle-based programs. These are addressed in Section 6.2, Interventions Aimed at Changing Patient Behavior. Recommendation-Specific Supportive Text 1. 