Association of Physical Activity With Changes in Skeletal Muscle Mass in Patients With Acute Stroke

Reduced skeletal muscle mass in patients with stroke is associated with poor clinical outcomes. Although physical activity helps mitigate this loss, the relationship between physical activity and changes in skeletal muscle mass remains unclear. This study examined the association between changes in skeletal muscle mass and physical activity in patients with acute stroke, including those with moderate-to-severe stroke. This retrospective cohort study evaluated 167 patients who were consecutively admitted within 48 hr of stroke onset between December 2022 and March 2024 based on data extracted from hospital medical records. The dependent variable was the change in skeletal muscle mass (in kilograms), and the independent variables were light- (LPA) and moderate- to vigorous-intensity physical activity (in minutes per day) and the National Institutes of Health Stroke Scale score. Associations were examined using multiple regression analysis. There was a significant loss of skeletal muscle mass during hospitalization (mean change: -1.5 kg [SD: 1.6], p < .001). Of the 167 patients, 120 were in the mild stroke group and 47 in the moderate-to-severe group. LPA was significantly associated with reduced skeletal muscle mass loss in the mild stroke group (B = 0.004, 95% confidence interval [0.001, 0.007], p = .009, adjusted R2 = .24). No significant association was detected in the moderate-to-severe group. Patients with acute stroke experienced significant skeletal muscle mass loss during hospitalization. LPA was independently associated with less skeletal muscle mass loss in the mild stroke group. The findings suggest that increasing LPA may help prevent skeletal muscle mass loss in patients with mild acute stroke.