title: Oxygen uptake during walking in patients with rheumatoid arthritis--a controlled study.
abstract: OBJECTIVE
  To analyze the energy expenditure of patients with rheumatoid arthritis (RA) of functional classes I, II, and III during walking at different speeds on a treadmill.
  
  
  METHODS
  Thirty-five consecutive patients selected from the rheumatology outpatient clinic were studied and compared with a control group consisting of 35 healthy individuals paired for age, sex, body weight, and body mass index. An incremental test on a treadmill consistent with normal walking was developed, with metabolic analysis performed at 30 s intervals using a gas analyzer connected to a computerized system. Heart rate, rate of perceived exertion, visual analog scale of pain, Ritchie index, the Scale of the Escola Paulista de Medicina for Evaluation of Articular Movement Range, and the Health Assessment Questionnaire were also used to evaluate functional capacity.
  
  
  RESULTS
  Patients with RA showed a greater energy expenditure than controls at the following walking speeds: 3.0 km/h (RA = 229.36 +/- 56.47 kcal/h; controls = 197.44 +/- 52.59), 4.5 km/h (RA = 266.41 +/- 58.94 kcal/h; controls = 231.41 +/- 56.14), and 5.0 km/h (RA = 289.11 +/- 65.35 kcal/h; controls = 250.18 +/- 56.67). Patients with RA presented higher values for all test measures except heart rate. The functional class II group differed significantly from the controls, whereas the functional class I group had values close to normal.
  
  
  CONCLUSIONS
  Patients with RA had a greater energy expenditure during walking compared to healthy controls under the same conditions, and patients with functional class II experienced a greater energy expenditure compared to controls.
authors.affiliation: Department of Medicine, Rheumatology Division, and Medical Center of Sports and Physical Activity, Universidade Federal de São Paulo/Escola Paulista de Medicina, São Paulo, Brazil. rosecarv@terra.com.br
authors.forename: Maria Rosenilda Petronila
authors.initials: MR
authors.lastname: de Carvalho
authors.forename: Antonio Sergio
authors.initials: AS
authors.lastname: Tebexreni
authors.forename: Carlos A F
authors.initials: CA
authors.lastname: Salles
authors.forename: Turibio
authors.initials: T
authors.lastname: Barros Neto
authors.forename: Jamil
authors.initials: J
authors.lastname: Natour
mesh_terms: D000328:Adult; D001172:Arthritis, Rheumatoid / Q000378:metabolism* / Q000503:physiopathology; D004734:Energy Metabolism; D005080:Exercise Test; D005260:Female; D006304:Health Status; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D010101:Oxygen Consumption; D010147:Pain Measurement; D005082:Physical Exertion; D016059:Range of Motion, Articular; D012720:Severity of Illness Index; D016138:Walking / Q000502:physiology*