Table of Contents Author Guidelines Submit a Manuscript
Multiple Sclerosis International
Volume 2014, Article ID 162765, 7 pages
http://dx.doi.org/10.1155/2014/162765
Clinical Study

Oxygen Cost of Walking in Persons with Multiple Sclerosis: Disability Matters, but Why?

Department of Kinesiology and Community Health, University of Illinois at Urbana-Champaign, 233 Freer Hall, 906 South Goodwin Avenue, Urbana, IL 61801, USA

Received 30 October 2013; Accepted 6 January 2014; Published 6 March 2014

Academic Editor: Wolfgang Bruck

Copyright © 2014 Brian M. Sandroff et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Background. The oxygen cost (O2 cost) of walking is elevated in persons with MS, particularly as a function of increasing disability status. Objective. The current study examined symptomatic (i.e., fatigue, pain, anxiety, and depression) and gait (i.e., velocity, cadence, and step length) variables that might explain why disability status is associated with O2 cost of walking in persons with MS. Materials and Methods. 82 participants completed the Patient-Determined Disease Steps, Fatigue Severity Scale, McGill Pain Questionnaire, and Hospital Anxiety and Depression Scale and undertook 2 trials of walking on a GAITRite electronic walkway. Participants then completed a six-minute walk test with concurrent assessment of expired gases for quantifying oxygen consumption and O2 cost of walking. Results. Disability ( ) as well as fatigue ( ), gait velocity ( ), cadence ( ), and step length ( ) were associated with the O2 cost of walking. Cadence ( ), but not step length ( ) or fatigue ( ), explained the association between disability and the O2 cost of walking. Conclusions. These results highlight cadence as a target of rehabilitation for increasing metabolic efficiency during walking among those with MS, particularly as a function of worsening disability.