PURPOSE:: Physical activity within the hospital poststroke is recommended for cardiovascular and musculoskeletal health, but no studies have examined cerebrovascular health. We hypothesized that individuals who walked farther distances (FARhigh) during the acute phase of stroke recovery in a hospital setting would have a higher resting middle cerebral artery blood velocity (MCAv) and a greater cerebrovascular response (CVR) to moderate-intensity exercise at 3 months poststroke, compared with individuals who walked shorter distances (FARlow). METHODS:: At 3 months poststroke, we recorded 90 seconds of resting baseline (BL) MCAv, followed by 6 minutes of moderate-intensity exercise. We calculated CVR as the change in MCAv from BL to steady-state exercise. We retrospectively collected the farthest distance walked within the hospital poststroke from the electronic medical record. Participants were classified as FARhigh or FARlow based on the average farthest walking distance. RESULTS:: Twenty participants completed the study, aged 63 (15) years. Baseline MCAv was not different between groups (P = .07). In comparison with FARlow, we report a higher CVR in FARhighʼs ipsilesional ((Equation is included in full-text article.) = 7.38 [5.42] vs (Equation is included in full-text article.) = 2.19 [3.53], P = .02)and contralesional hemispheres ((Equation is included in full-text article.) = 8.15 [6.37] vs (Equation is included in full-text article.) = 2.06 [4.76], P = .04). CONCLUSIONS:: Physical activity during the hospital stay poststroke may support cerebrovascular health after discharge. Prospective studies are needed to support this finding.