title: Impaired postural control reduces sit-to-stand-to-sit performance in individuals with chronic obstructive pulmonary disease.
abstract: BACKGROUND
  Functional activities, such as the sit-to-stand-to-sit (STSTS) task, are often impaired in individuals with chronic obstructive pulmonary disease (COPD). The STSTS task places a high demand on the postural control system, which has been shown to be impaired in individuals with COPD. It remains unknown whether postural control deficits contribute to the decreased STSTS performance in individuals with COPD.
  
  
  METHODS
  Center of pressure displacement was determined in 18 individuals with COPD and 18 age/gender-matched controls during five consecutive STSTS movements with vision occluded. The total duration, as well as the duration of each sit, sit-to-stand, stand and stand-to-sit phase was recorded.
  
  
  RESULTS
  Individuals with COPD needed significantly more time to perform five consecutive STSTS movements compared to healthy controls (19±6 vs. 13±4 seconds, respectively; p = 0.001). The COPD group exhibited a significantly longer stand phase (p = 0.028) and stand-to-sit phase (p = 0.001) compared to the control group. In contrast, the duration of the sit phase (p = 0.766) and sit-to-stand phase (p = 0.999) was not different between groups.
  
  
  CONCLUSIONS
  Compared to healthy individuals, individuals with COPD needed significantly more time to complete those phases of the STSTS task that require the greatest postural control. These findings support the proposition that suboptimal postural control is an important contributor to the decreased STSTS performance in individuals with COPD.
authors.affiliation: KU Leuven Department of Rehabilitation Sciences, University of Leuven, Leuven, Belgium.
authors.forename: Lotte
authors.initials: L
authors.lastname: Janssens
authors.affiliation: KU Leuven Department of Rehabilitation Sciences, University of Leuven, Leuven, Belgium.
authors.forename: Simon
authors.initials: S
authors.lastname: Brumagne
authors.affiliation: Centre for Sports Medicine and Human Performance, Brunel University, Uxbridge, United Kingdom.
authors.forename: Alison K
authors.initials: AK
authors.lastname: McConnell
authors.affiliation: KU Leuven Department of Rehabilitation Sciences, University of Leuven, Leuven, Belgium ; KU Leuven Department of Rehabilitation Sciences, University of Leuven KULAB, Bruges, Belgium.
authors.forename: Kurt
authors.initials: K
authors.lastname: Claeys
authors.affiliation: KU Leuven Department of Rehabilitation Sciences, University of Leuven, Leuven, Belgium.
authors.forename: Madelon
authors.initials: M
authors.lastname: Pijnenburg
authors.affiliation: KU Leuven Department of Rehabilitation Sciences, University of Leuven, Leuven, Belgium.
authors.forename: Nina
authors.initials: N
authors.lastname: Goossens
authors.affiliation: KU Leuven Department of Rehabilitation Sciences, University of Leuven, Leuven, Belgium ; Respiratory Rehabilitation and Respiratory Division, University Hospital Leuven, Leuven, Belgium ; Department of Allied Health Professions, Fontys University of Applied Sciences, Eindhoven, Netherlands.
authors.forename: Chris
authors.initials: C
authors.lastname: Burtin
authors.affiliation: Respiratory Rehabilitation and Respiratory Division, University Hospital Leuven, Leuven, Belgium.
authors.forename: Wim
authors.initials: W
authors.lastname: Janssens
authors.affiliation: KU Leuven Department of Rehabilitation Sciences, University of Leuven, Leuven, Belgium ; Respiratory Rehabilitation and Respiratory Division, University Hospital Leuven, Leuven, Belgium.
authors.forename: Marc
authors.initials: M
authors.lastname: Decramer
authors.affiliation: KU Leuven Department of Rehabilitation Sciences, University of Leuven, Leuven, Belgium ; Respiratory Rehabilitation and Respiratory Division, University Hospital Leuven, Leuven, Belgium.
authors.forename: Thierry
authors.initials: T
authors.lastname: Troosters
mesh_terms: D000368:Aged; D000886:Anthropometry; D001696:Biomechanical Phenomena; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009068:Movement; D004856:Postural Balance; D029424:Pulmonary Disease, Chronic Obstructive / Q000503:physiopathology*; D012984:Software; D011795:Surveys and Questionnaires; D014785:Vision, Ocular