Energy cost of walking and its association with gait parameters, daily activity, and fatigue in persons with mild multiple sclerosis

Background. Energy cost of walking (C_w) is elevated in persons with multiple sclerosis (MS), perhaps because of gait impairment, and may impact daily activity and fatigue. Objective. The authors examined for associations between C_w, spatiotemporal gait parameters, daily activity, and perceived fatigue in persons with mild MS. Methods. Forty-four participants completed 4 trials of walking on a GAITRite mat and one 6-minute trial of walking on a treadmill at a constant, controlled speed of 54 m min-1 while expired gases were analyzed for oxygen consumption. Participants also completed the Fatigue Severity Scale (FSS) and wore a waist-mounted accelerometer for 7 days. Results. C_w was significantly and inversely associated with gait speed (r = -.25) and stride length (r = -.32) and positively associated with double limb support (r =.27). C_w was significantly and inversely associated with daily accelerometer activity counts (r = -.35) and positively associated with FSS scores (ρ =.31). Conclusion. The results support the development and application of rehabilitation strategies to address impaired gait parameters as an approach to improve C_w, daily activities, and fatigue.