Physical Activity Associated With Early Independent Walking in Nonambulatory Patients With Subacute Stroke

BACKGROUND: Identifying the intensity and frequency of physical activity associated with early independent walking in nonambulatory patients with subacute stroke may inform daily physical activity promotion during hospitalization, which was the aim of the present study. METHODS: This multicenter prospective cohort study was conducted at 11 facilities. Baseline was defined as admission to a subacute rehabilitation ward, with subacute referring to the phase after completion of acute stroke treatment. Patients with subacute stroke and a Functional Ambulation Category of 1 to 2 at admission were included. Physical activity was measured using an accelerometer for 1 week at baseline. The outcome was achievement of independent walking at 1 month from baseline (Functional Ambulation Category ≥4). To examine the intensity of physical activity associated with the outcome, modified Poisson regression was used to evaluate time spent in low -intensity physical activity (LPA; low-LPA, 1.6-1.9 metabolic equivalents [METs]), high-LPA (2.0-2.9 METs), and moderate-to-vigorous intensity physical activity (≥3.0 METs). Furthermore, to assess frequency associated with activity intensity, bouts of physical activity at or above the intensity level (≥1.6, ≥2.0, or ≥3.0 METs) were calculated as short-bouts (≥5 to <10 minutes) and long-bouts (≥10 minutes), and their associations with the outcome were examined. RESULTS: Of 389 participants (mean age, 68.1 years; 45.0% female), 113 achieved independent walking during follow-up. Time spent in high-LPA was associated with independent walking when expressed per 5 min/d (risk ratio, 1.067 [95% CI, 1.010-1.131]), whereas low-LPA and moderate-to-vigorous intensity physical activity were not. The number of short-bouts at ≥2.0 METs was associated with independent walking (risk ratio, 1.208 [95% CI, 1.060-1.375]), whereas long-bouts were not relevant. CONCLUSIONS: Accumulation of high-LPA and short-bouts at ≥2.0 METs was associated with early independent walking. These findings may help characterize activity intensity and bout frequency associated with walking independence in nonambulatory patients with subacute stroke during inpatient rehabilitation. REGISTRATION: URL: https://www.umin.ac.jp/ctr; Unique identifier: UMIN000058526.