The Influence of Acute Bouts of Aerobic Exercise on Neuroplasticity and Motor Learning After Stroke

All participants will complete baseline sessions: 1) sub-maximal exercise test to ensure safe participation in aerobic exercise (testing session [s] 1); and 2) magnetic resonance imaging (MRI) to assess brain structure and function, and 3) clinical assessments of motor function and activity. The MRI and clinical tests will be completed on s2. Between the exercise test and MRI sessions individuals will wear accelerometers for 3 days to index usual activity levels. A custom computer program will then assign participants quasi-randomly to either the rest or exercise groups stratified on age, sex, and baseline motor function. Cortical excitability will be assessed before and after either a single session of priming aerobic exercise, or rest, by group (s3). Next, priming exercise will be paired with skilled motor practice for 5 sessions (s4-8). Practice sessions will be separated by 48 hours. Importantly motor learning will be assessed via delayed, no-exercise retention tests 24-hours (s9) and 30-days (s11) after the last practice session. Activity levels (3 day accelerometry), TMS and MRI measures will be re-assessed after the second retention test (s10).