Mobility-related fatigue, walking speed, and muscle strength in older people

Abstract

Background. Fatigue is an important early marker of functional decline among older people, but the mechanisms underlying this association are not fully understood. The purpose of the present study was to examine the association between mobility-related fatigue and walking speed and to test the degree to which muscle strength accounts for this association. Methods. The study is based on baseline (n = 523) and 5-year follow-up data (n = 292) from a cohort of 75-year-old persons. Standardized assessments include self-report measures of mobility-related fatigue (score range 0-6) and medical history, as well as performance-based assessment of walking speed and maximal isometric strength of knee extension, body extension, and handgrip. Results. In the cross-sectional baseline analysis, one unit increase in fatigue score was associated with 0.03 m/s (β =-.03, p