Association of Physical Activity and Nutritional Intake with Muscle Quantity and Quality Changes in Acute Stroke Patients.

Objectives: To evaluate longitudinally the muscle properties of acute stroke patients and examine the association between physical activity and nutritional intake.

Materials And Methods: This study enrolled 21 stroke patients (72.7±10.4 years). Muscle quantity (fat-free mass, appendicular skeletal muscle mass) and quality (extracellular water/intracellular water ratio, phase angle) were assessed using a bioelectrical impedance device at baseline (within three days) and two weeks after stroke onset. Physical activity and sedentary were calculated from the accelerometer data. Total energy and protein intake were calculated from the dietary surveys as nutritional intake. The association of physical activity, sedentary, and nutritional intake with the rate of changes in muscle properties was examined.

Results: The fat-free mass significantly decreased (from 43.4±8.0 to 42.2±7.6 kg), and the skeletal muscle was unchanged (from 17.8±4.2 to 17.7±4.0 kg) after two weeks. The extracellular water/intracellular water ratio significantly increased (from 0.63±0.02 to 0.65±0.03) and the phase angle significantly decreased (from 5.1±0.6 to 4.9±0.8°), suggesting that the muscle quality have declined. Correlation analysis showed that the extracellular water/intracellular water ratio was significantly associated with physical activity [metabolic equivalents (ρ=-0.61)] and sedentary (ρ=0.67) and that the phase angle was significantly associated with physical activity [metabolic equivalents (ρ=0.69)], sedentary (ρ=-0.68), and nutritional intake [total energy (r=0.45), protein (r=0.45)].

Conclusions: The fat-free mass and muscle quality (extracellular water/intracellular water ratio and phase angle) declined two weeks after stroke. Physical activity and nutritional intake were lower in patients with decreased muscle quality, suggesting the importance of exercise and nutrition in the acute phase.