title: Incremental shuttle walking test: a reproducible and valid test to evaluate exercise tolerance in adults with noncystic fibrosis bronchiectasis.
abstract: OBJECTIVE
  To analyze the reliability, validity, and determinants of the incremental shuttle walk test (ISWT) in adults with noncystic fibrosis bronchiectasis.
  
  
  METHODS
  Cross-sectional study.
  
  
  METHODS
  Outpatient clinic.
  
  
  METHODS
  Subjects (N=75; 26 men) underwent, on different days, cardiopulmonary exercise testing (CPET) and 2 ISWTs, 30 minutes apart. The number of steps in daily life was recorded. Concurrent validity was tested by the relation between distance walked with peak load and oxygen consumption (V˙o2).
  
  
  METHODS
  None.
  
  
  METHODS
  Distance walked (m) was compared between the first and second ISWTs; greatest distance walked was correlated with peak load and Vo2peak obtained from CPET, steps per day, and dyspnea evaluated by the Medical Research Council (MRC) scale; and desaturation was compared between CPET and the ISWT.
  
  
  RESULTS
  Distance walked was equivalent between the first ISWT (441±152m) and the second ISWT (445±153m) with an excellent intraclass correlation coefficient (.995; 95% confidence interval, .99-.997). There were significant correlations between distance walked and peak load (r=.82), V˙o2 (r=.72), steps per day (r=.61), and the MRC scale (r=-.69). Age, body mass index, sex, forced vital capacity (% predicted), dyspnea, and steps per day explained 70% of the variation in distance walked (m) and 60% of the variance when expressed as percent predicted. Higher desaturation was observed during the ISWT (-4%±4%) than cycling (-2±3%) (P<.001).
  
  
  CONCLUSIONS
  The ISWT is reliable, represents functional capacity, and induces greater desaturation than cycling. Age, body composition, pulmonary function, dyspnea, and physical activity in daily life are determinants of the distance walked on the ISWT.
authors.affiliation: Postgraduate Program in Rehabilitation Sciences, Nove de Julho University, São Paulo, Brazil.
authors.forename: Anderson Alves
authors.initials: AA
authors.lastname: de Camargo
authors.affiliation: Postgraduate Program in Rehabilitation Sciences, Nove de Julho University, São Paulo, Brazil.
authors.forename: Tatiane S
authors.initials: TS
authors.lastname: Amaral
authors.affiliation: Pulmonary Division, Heart Institute, University of São Paulo School of Medicine, São Paulo, Brazil.
authors.forename: Samia Z
authors.initials: SZ
authors.lastname: Rached
authors.affiliation: Pulmonary Division, Heart Institute, University of São Paulo School of Medicine, São Paulo, Brazil.
authors.forename: Rodrigo A
authors.initials: RA
authors.lastname: Athanazio
authors.affiliation: Postgraduate Program in Rehabilitation Sciences, Nove de Julho University, São Paulo, Brazil.
authors.forename: Fernanda C
authors.initials: FC
authors.lastname: Lanza
authors.affiliation: Postgraduate Program in Rehabilitation Sciences, Nove de Julho University, São Paulo, Brazil.
authors.forename: Luciana M
authors.initials: LM
authors.lastname: Sampaio
authors.affiliation: Physiotherapy Department, Department of Physical Therapy, University of São Paulo School of Medicine, São Paulo, Brazil.
authors.forename: Celso R
authors.initials: CR
authors.lastname: de Carvalho
authors.affiliation: Pulmonary Division, Heart Institute, University of São Paulo School of Medicine, São Paulo, Brazil.
authors.forename: Alberto
authors.initials: A
authors.lastname: Cukier
authors.affiliation: Pulmonary Division, Heart Institute, University of São Paulo School of Medicine, São Paulo, Brazil.
authors.forename: Rafael
authors.initials: R
authors.lastname: Stelmach
authors.affiliation: Postgraduate Program in Rehabilitation Sciences, Nove de Julho University, São Paulo, Brazil. Electronic address: simonedc@uninove.br.
authors.forename: Simone
authors.initials: S
authors.lastname: Dal Corso
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015992:Body Mass Index; D001987:Bronchiectasis / Q000473:pathology / Q000503:physiopathology* / Q000534:rehabilitation; D003430:Cross-Sectional Studies; D005080:Exercise Test / Q000379:methods*; D017079:Exercise Tolerance / Q000502:physiology*; D005260:Female; D005355:Fibrosis / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D010101:Oxygen Consumption; D015203:Reproducibility of Results; D016138:Walking / Q000502:physiology*; D055815:Young Adult
keywords: Bronchiectasis; Exercise test; Exercise tolerance; Rehabilitation