Potential Predictors of Peak Aerobic Capacity in Subacute Stroke Patients

Objective: To investigate the potential predictors of peak aerobic capacity in subacute stroke patients among body composition, balance function, walking capacity, and lower limb muscle strengths, and to compare the clinical functional outcomes with respect to balance function and gender.
Methods: This study was a descriptive, observational, cross-sectional study. Eighty-three subacute stroke patients were enrolled in the study (47 males and 36 females; mean age: 62.95 ± 13.9 years). Gait capacity was assessed by gait velocity (10 m walk velocity: 10MWV) and gait endurance (6 minute walk distance: 6MWD). Balance function was evaluated with the Korean version of the Berg Balance Scale (K-BBS). The isometric muscle strengths of bilateral knee flexors and extensors were measured with an isokinetic dynamometer. Cardiovascular fitness was evaluated with an expired gas analyzer. Body composition was measured with a bioelectrical impedance analysis device. We attempted to identify the major determinants of peak aerobic capacity in subacute stroke patients and to compare clinical functional outcomes with respect to balance function and gender.
Results: In backward linear regression analyses, paretic isometric extensor strength (𝑝 < 0.001), fat mass (𝑝 = 0.005), and 10MWV (𝑝 < 0.001) were independent predictors of peak aerobic capacity (adjusted R² = 0.449) in all patients. In addition, VO_2peak, K-BBS, 10MWV, 6MWD, and paretic knee extensor and flexor strength significantly differed between the dependent and independent ambulatory groups (𝑝 < 0.05). Muscle mass, both knee extensor and flexor strength, and VO_2peak significantly differed between males and females (𝑝 < 0.05).
Conclusions: Our results confirmed that paretic knee extensor strength, gait velocity, and fat mass were major determinants of peak aerobic capacity in subacute stroke patients. Therefore, therapeutic approaches should focus on improving gait velocity and paretic knee extensor strength and on managing fat mass in the early stages of recovery from stroke.