| Abstrakt: |
Purpose: Measurements obtained during maximal cardiopulmonary exercise testing (CPET) demonstrate high test-retest reliability, which indicates low error variance. However, measurements obtained from people with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) may depart from typically observed high reproducibility, which could represent functionally relevant biological variability that is characteristic of the underlying pathophysiology. The purpose of this case series was to document individual experiences with test-retest variability in CPET measurements in individuals with ME/CFS compared with other fatiguing health conditions. Methods: In this case series, 6womenmatched for age and body mass index underwent 2 maximal CPETs spaced 24 hours apart. Clients comprised 1 sedentary individual without fatigue, 1 active individual without fatigue, 1 individualwithmultiple sclerosis (MS), 1 individual diagnosed with HIV, 1 individual withME/CFS and lowmaximal volume of oxygen consumed (VO2max), and 1 high-functioning individual with ME/CFS and high VO2max. Percent change in CPET measurements between tests was calculated for each client. Results: Nondisabled clients and clients withMSandHIV reproduced or improved in their volume of oxygen consumed(VO2), workload (WL), heart rate (HR), andminute ventilation (VE) at ventilatory anaerobic threshold (VAT) and at peak exercise (except peakWLandVE for the individual with HIV). Neither individual with ME/CFS reproduced VO2, WL, HR, or VE at VAT within literature estimates. Conclusions: Measurements during CPET for individual patients may relate to potential condition-specific deficits in cardiac, pulmonary, and metabolic functioning. [ABSTRACT FROM AUTHOR] |
