title: Validity of maximal exercise testing in people with multiple sclerosis and low to moderate levels of disability.
abstract: BACKGROUND
  Cardiopulmonary exercise testing can be considered the gold standard for assessing cardiorespiratory fitness. Little is known about the criteria for maximal exercise testing in people with multiple sclerosis (MS) and how these criteria behave across different levels of neurological disability.
  
  
  OBJECTIVE
  The study objectives were to determine the criteria for maximal exercise testing across various levels of disability and to assess concomitant subgroup differences in measures related to the participant, disease, and function.
  
  
  METHODS
  This was a cross-sectional study.
  
  
  METHODS
  Cardiopulmonary exercise testing was conducted with a sample of 56 participants with MS. Analysis of variance was used to assess the criteria in participants with MS and low, mild, and moderate levels of disability.
  
  
  RESULTS
  Mean peak oxygen consumption (V̇o2peak) was 21.4 (SD=7.1) mL·kg(-1)·min(-1). An oxygen consumption (V̇o2) plateau was seen in 37.5% of participants. A respiratory exchange ratio of 1.10 or greater was achieved by 69.6% of the participants, a maximal heart rate within 90% of their age-predicted maximal heart rate was achieved by 48.2% of the participants, and 23.2% of the participants perceived their exertion to be 18 or greater on the Borg Scale of Perceived Exertion (scores of 6-20). The values for achieved heart rate and incidence of a V̇o2 plateau were significantly lower in participants with moderate levels of disability than in those with mild levels of disability.
  
  
  CONCLUSIONS
  The primary limitations of this study were its cross-sectional nature and relatively small sample of participants with moderate levels of disability.
  
  
  CONCLUSIONS
  The findings suggest that the outcome of cardiopulmonary exercise testing in people with MS and low to mild levels of disability (Expanded Disability Status Scale scores of ≤4.0) is a valid measure of cardiorespiratory fitness, whereas the outcome in people with moderate levels of disability (Expanded Disability Status Scale scores of >4.0) is most likely symptom limited.
authors.affiliation: M. Heine, MSc, Brain Center Rudolf Magnus and Center of Excellence for Rehabilitation Medicine, University Medical Center Utrecht and Rehabilitation Center De Hoogstraat, Rembrandtkade 10, 3583 TM Utrecht, the Netherlands. m.heine@dehoogstraat.nl.
authors.forename: Martin
authors.initials: M
authors.lastname: Heine
authors.affiliation: E.L.J. Hoogervorst, MD, PhD, Multiple Sclerosis Center, St Antonius Hospital, Nieuwegein, the Netherlands.
authors.forename: Erwin L J
authors.initials: EL
authors.lastname: Hoogervorst
authors.affiliation: H.G.A. Hacking, MD, Multiple Sclerosis Center, St Antonius Hospital.
authors.forename: Hub G A
authors.initials: HG
authors.lastname: Hacking
authors.affiliation: O. Verschuren, PhD, Brain Center Rudolf Magnus and Center of Excellence for Rehabilitation Medicine, University Medical Center Utrecht and Rehabilitation Center De Hoogstraat.
authors.forename: Olaf
authors.initials: O
authors.lastname: Verschuren
authors.affiliation: G. Kwakkel, PhD, Department of Rehabilitation Medicine, MOVE Research Institute Amsterdam, VU University Medical Center, and Department of Neurorehabilitation, Centre of Rehabilitation and Rheumatology Reade, Amsterdam, the Netherlands.
authors.forename: Gert
authors.initials: G
authors.lastname: Kwakkel
mesh_terms: D000328:Adult; D003430:Cross-Sectional Studies; D004185:Disability Evaluation; D006233:Persons with Disabilities / Q000706:statistics & numerical data*; D005080:Exercise Test; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000503:physiopathology*; D010101:Oxygen Consumption / Q000502:physiology; D010809:Physical Fitness / Q000502:physiology*