Energy expenditure and cost of walking and stair climbing in individuals with chronic stroke

BACKGROUND Subjects with stroke show higher energy cost (EC) during walking, when compared to healthy individuals, but the mechanisms are not fully understood. Additionally, the behavior of physiological variables during other activities has not been investigated. OBJECTIVES To investigate energy expenditure (EE) and EC during the six-minute walking test (6MWT) and stair climb test (SCT) in chronic stroke subjects compared to healthy controls. METHODS Cross-sectional study in which stroke subjects (n=18) (community-walking speed ≥0.8m/s) or limited-community <0.8m/s walkers and matched healthy controls (n=18) had their EE and EC assessed during the 6MWT and SCT with a portable monitoring system. RESULTS Significant differences in EE were observed for both the 6MWT (MD 7.29; 95%CI 4.08-10.50) and SCT (MD 8.53; 95%CI 5.07-12.00) between the stroke and control groups, but not between the stroke subgroups. Significant between-group differences in EC were found for both the 6MWT and SCT. For the 6MWT, differences were significant between the limited-community and the community walkers (MD 0.19; 95%CI 0.05-0.33) and controls (MD 0.17; 95%CI 0.04-0.29). No significant differences were found between the community walkers and controls (MD 0.02; 95%CI -0.09 to 0.13). For the SCT, the limited-community walkers showed highest EC, followed by the community walkers, and controls. CONCLUSIONS Both stroke subgroups demonstrated lower EE compared to healthy controls. During the 6MWT, the limited-community walkers demonstrated higher EC compared to the community walkers and controls. During the SCT, the limited-community walkers demonstrated higher EC, followed by the community walkers, and controls.