Aerobic Exercise Improves Cognition and Motor Function Poststroke

Abstract
Background. Cognitive deficits impede stroke recovery. Aerobic exercise (AEX) improves cognitive executive function (EF) processes in healthy individuals, although the learning benefits after stroke are unknown. Objective. To understand AEX-induced improvements in EF, motor learning, and mobility poststroke. Methods. Following cardiorespiratory testing, 38 chronic stroke survivors were randomized to 2 different groups that exercised 3 times a week (45-minute sessions) for 8 weeks. The AEX group (n = 19; 9 women; 10 men; 64.10 ± 12.30 years) performed progressive resistive stationary bicycle training at 70% maximal heart rate, whereas the Stretching Exercise (SE) group (n = 19; 12 women; 7 men; 58.96 ± 14.68 years) performed stretches at home. Between-group comparisons were performed on the change in performance at “Post” and “Retention” (8 weeks later) for neuropsychological and motor function measures. Results. VO2max significantly improved at Post with AEX ( P = .04). AEX also improved motor learning in the less-affected hand, with large effect sizes (Cohen’s d calculation). Specifically, AEX significantly improved information processing speed on the serial reaction time task (SRTT; ie, “procedural motor learning”) compared with the SE group at Post ( P = .024), but not at Retention. Also, at Post ( P = .038), AEX significantly improved predictive force accuracy for a precision grip task requiring attention and conditional motor learning of visual cues. Ambulation and sit-to-stand transfers were significantly faster in the AEX group at Post ( P = .038), with balance control significantly improved at Retention ( P = .041). EF measurements were not significantly different for the AEX group. Conclusion. AEX improved mobility and selected cognitive domains related to motor learning, which enhances sensorimotor control after stroke.