Purpose: To examine the physiological cost of walking in subjects with chronic fatigue syndrome (CFS) and a matched control group, walking at their preferred and at matched walking speeds.
Methods: Seventeen people with CFS and 17 matched-controls participated in this observational study of physiological cost during over-ground gait. Each subject walked for 5 min at their preferred walking speed (PWS). Controls then walked for 5 min at the same pace of their matched CFS subject. Gait speed and oxygen uptake, gross and net were measured and oxygen uptake was expressed per unit distance ambulated. CFS subjects completed the CFS-Activities and Participation Questionnaire (CFS-APQ).
Results: At PWS the CFS group walked at a slower velocity of 0.84 +/- 0.21 m s(-1) compared to controls with a velocity of 1.19 +/- 0.13 m s(-1) (p < 0.001). At PWS both gross and net oxygen uptake of CFS subjects was significantly less than controls (p = 0.023 and p = 0.025 respectively). At matched-velocity both gross and net physiological cost of gait was greater for CFS subjects than controls (p = 0.048 and p = 0.001, respectively).
Conclusion: The physiological cost of walking was significantly greater for people with CFS compared with healthy subjects. The reasons for these higher energy demands for walking in those with CFS have yet to be fully elucidated.