Objective: To measure the association between walking velocity and hip and knee flexion range, ethnic background, anthropometrics, comorbid pathologies, and coimpairments, in a sample of community-dwelling aged persons.
Methods: To reach our objective, we used data from the San Antonio Longitudinal Study of Aging (SALSA), a population-based cohort of Mexican American and European American persons aged 64 to 79. By fitting hierarchical regression models, we measured the variance in the walking velocity over 50 feet explained by hip and knee flexion range, adjusting for the combined influence of demographic and anthropometric variables, coexistent pathologic conditions, impairments, and the examiners who conducted the assessments.
Results: The average walking velocity among the 702 subjects for whom data were available was 73.6 meters per minute (range 20 to 121). Bivariate analyses revealed significant associations between walking velocity and age, sex, ethnic background, height, weight, presence of arthritis, diabetes mellitus, stroke, upper leg pain, peripheral vascular disease, left ventricular hypertrophy, and forced expiratory volume at 1 second. The correlation (r) between walking velocity and flexion range of the hip and knee were 0.40 and 0.35, respectively (P < or = 0.001 for each). Multivariate hierarchical models adjusting for demographic and anthropometric characteristics of the subjects, and examiner variation, revealed that hip and knee flexion range explained 6% of the variance in walking velocity. Adjusting for the presence of comorbid conditions and coimpairments reduced the variance attributable to hip and knee flexion range only slightly, to 5%.
Conclusion: Hip and knee flexion range contribute significantly to walking velocity in the SALSA cohort of community-dwelling aged persons.