Secondary Analysis of Walking Activities during the Acute Stroke Hospital Stay and Cerebrovascular Health.

Purpose: Physical activity within the hospital post-stroke is recommended for cardiovascular and musculoskeletal health, but no studies have examined cerebrovascular health. We hypothesized 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 post-stroke, compared to individuals who walked shorter distances (FARlow).

Methods: At 3-month post-stroke, 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 farthest distance walked within the hospital post-stroke from the electronic medical record. Participants were classified as FARhigh or FARlow based on average farthest walking distance.

Results: Twenty participants completed the study, age 63 (15) years. BL MCAv was not different between groups (p = 0.07). In comparison to FARlow, we report a higher CVR in FARhigh's ipsilesional ( $\overline{x}$ = 7.38 (5.42) vs $\overline{x}$ = 2.19 (3.53), p = 0.02) and contralesional hemisphere ( $\overline{x}$ = 8.15 (6.37) vs $\overline{x}$ = 2.06 (4.76), p = 0.04).

Conclusions: Physical activity during the hospital stay post-stroke may support cerebrovascular health after discharge. Prospective studies are needed to support this finding.