title: Effects of treadmill exercise versus Flutter® on respiratory flow and sputum properties in adults with cystic fibrosis: a randomised, controlled, cross-over trial.
abstract: Treadmill exercise and airway clearance with the Flutter® device have previously been shown to improve mucus clearance mechanisms in people with cystic fibrosis (CF) but have not been compared. It is therefore not known if treadmill exercise is an adequate form of airway clearance that could replace established airway clearance techniques, such as the Flutter®. The aim of this study was to evaluate respiratory flow, sputum properties and subjective responses of treadmill exercise and Flutter® therapy, compared to resting breathing (control).
  
  
  
  Twenty-four adults with mild to severe CF lung disease (FEV128-86% predicted) completed a three-day randomised, controlled, cross-over study. Interventions consisted of 20 min of resting breathing (control), treadmill exercise at 60% of the participant's peak oxygen consumption and Flutter® therapy. Respiratory flow was measured during the interventions. Sputum properties (solids content and mechanical impedance) and subjective responses (ease of expectoration and sense of chest congestion) were measured before, immediately after the interventions and after 20 min of recovery.
  
  
  
  Treadmill exercise and Flutter® resulted in similar significant increases in peak expiratory flow, but only Flutter® created an expiratory airflow bias (i.e. peak expiratory flow was at least 10% higher than peak inspiratory flow). Treadmill exercise and Flutter® therapy resulted in similar significant reductions in sputum mechanical impedance, but only treadmill exercise caused a transient increase in sputum hydration. Treadmill exercise improved ease of expectoration and Flutter® therapy improved subjective sense of chest congestion.
  
  
  
  A single bout of treadmill exercise and Flutter® therapy were equally effective in augmenting mucus clearance mechanisms in adults with CF. Only longer term studies, however, will determine if exercise alone is an adequate form of airway clearance therapy that could replace other airway clearance techniques.
  
  
  
  Australian and New Zealand Clinical Trials Registry, Registration number # ACTRN12609000168257 , Retrospectively registered (Date submitted to registry 26/2/2009, First participant enrolled 27/2/2009, Date registered 6/4/2009).
authors.affiliation: Discipline of Physiotherapy, Faculty of Health Sciences, University of Sydney, Sydney, Australia. tiffany.dwyer@sydney.edu.au.|Department of Respiratory Medicine, Royal Prince Alfred Hospital, Sydney, Australia. tiffany.dwyer@sydney.edu.au.|Central Clinical School, Sydney Medical School, University of Sydney, Sydney, Australia. tiffany.dwyer@sydney.edu.au.
authors.forename: Tiffany J
authors.initials: TJ
authors.lastname: Dwyer
authors.affiliation: Discipline of Physiotherapy, Faculty of Health Sciences, University of Sydney, Sydney, Australia.|Rehabilitation Department, Ng Teng Fong General Hospital, Jurong Health Services, Jurong East, Singapore.|Health and Social Sciences, Academic Programme, Singapore Institute of Technology, Jurong East, Singapore.
authors.forename: Rahizan
authors.initials: R
authors.lastname: Zainuldin
authors.affiliation: Department of Respiratory Medicine, Royal Prince Alfred Hospital, Sydney, Australia.
authors.forename: Evangelia
authors.initials: E
authors.lastname: Daviskas
authors.affiliation: Department of Respiratory Medicine, Royal Prince Alfred Hospital, Sydney, Australia.|Central Clinical School, Sydney Medical School, University of Sydney, Sydney, Australia.
authors.forename: Peter T P
authors.initials: PT
authors.lastname: Bye
authors.affiliation: Discipline of Physiotherapy, Faculty of Health Sciences, University of Sydney, Sydney, Australia.|Department of Physiotherapy, Royal Prince Alfred Hospital, Sydney, Australia.
authors.forename: Jennifer A
authors.initials: JA
authors.lastname: Alison
mesh_terms: D000328:Adult; D001315:Australia; D035641:Chest Wall Oscillation / Q000379:methods*; D018592:Cross-Over Studies; D003550:Cystic Fibrosis / Q000628:therapy*; D005080:Exercise Test; D005081:Exercise Therapy / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010366:Peak Expiratory Flow Rate; D013183:Sputum / Q000502:physiology; D055815:Young Adult
keywords: Airway clearance; Cystic fibrosis; Exercise; Flutter®; Oscillating PEP; Physiotherapy; Sputum