title: Six-minute walking versus shuttle walking: responsiveness to bronchodilation in chronic obstructive pulmonary disease.
abstract: BACKGROUND
  The responsiveness of the endurance shuttle walk to functional changes following bronchodilation has recently been reported. The current literature suggests that the 6 min walking test (6MWT) is less responsive to bronchodilation than the endurance shuttle walk.
  
  
  OBJECTIVE
  To compare bronchodilator-induced changes in exercise performance with the 6MWT and the endurance shuttle walk.
  
  
  METHODS
  In a randomised, double-blind, placebo-controlled, crossover trial, 14 patients with chronic obstructive pulmonary disease (forced expiratory volume in 1 s (FEV(1)) 50 (8)% predicted) completed two 6MWTs and two endurance shuttle walks, each preceded by nebulised placebo or 500 microg ipratropium bromide. Cardiorespiratory parameters were monitored during each walking test with a portable telemetric gas analyser. Quadriceps twitch force was measured by magnetic stimulation of the femoral nerve before and after each walking test.
  
  
  RESULTS
  The 6 min walking distance did not change significantly after bronchodilation despite a significant increase in FEV(1) of 0.18 (0.09) litres (p<0.001). A similar change in FEV(1) (0.18 (0.12) litres, p<0.001) was associated with a significant improvement in the distance walked on the endurance shuttle walk (Deltadistance ipratropium bromide--placebo = 144 (219) m, p = 0.03). Quadriceps muscle fatigue was infrequent (<15% of patients) after both walking tests.
  
  
  CONCLUSIONS
  The endurance shuttle walk is more responsive than the 6MWT for detecting changes in exercise performance following bronchodilation.
authors.affiliation: Centre de Pneumologie, Hôpital Laval, 2725 Chemin Ste-Foy, Ste-Foy, Québec, G1V 4G5, Canada.
authors.forename: Véronique
authors.initials: V
authors.lastname: Pepin
authors.forename: Julie
authors.initials: J
authors.lastname: Brodeur
authors.forename: Yves
authors.initials: Y
authors.lastname: Lacasse
authors.forename: Julie
authors.initials: J
authors.lastname: Milot
authors.forename: Pierre
authors.initials: P
authors.lastname: Leblanc
authors.forename: François
authors.initials: F
authors.lastname: Whittom
authors.forename: François
authors.initials: F
authors.lastname: Maltais
mesh_terms: D000368:Aged; D001642:Bicycling; D001993:Bronchodilator Agents / Q000627:therapeutic use*; D004311:Double-Blind Method; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test; D005541:Forced Expiratory Volume / Q000502:physiology; D006801:Humans; D008875:Middle Aged; D029424:Pulmonary Disease, Chronic Obstructive / Q000188:drug therapy* / Q000503:physiopathology; D014797:Vital Capacity / Q000502:physiology; D016138:Walking / Q000502:physiology
chemical_list: D001993:Bronchodilator Agents