title: Age-related effects on postural control under multi-task conditions.
abstract: BACKGROUND
  Changes in postural sway and gait patterns due to simultaneously performed cognitive (CI) and/or motor interference (MI) tasks have previously been reported and are associated with an increased risk of falling in older adults.
  
  
  OBJECTIVE
  The objectives of this study were to investigate the effects of a CI and/or MI task on static and dynamic postural control in young and elderly subjects, and to find out whether there is an association between measures of static and dynamic postural control while concurrently performing the CI and/or MI task.
  
  
  METHODS
  A total of 36 healthy young (n = 18; age: 22.3 ± 3.0 years; BMI: 21.0 ± 1.6 kg/m(2)) and elderly adults (n = 18; age: 73.5 ± 5.5 years; BMI: 24.2 ± 2.9 kg/m(2)) participated in this study. Static postural control was measured during bipedal stance, and dynamic postural control was obtained while walking on an instrumented walkway.
  
  
  RESULTS
  Irrespective of the task condition, i.e. single-task or multiple tasks, elderly participants showed larger center-of-pressure displacements and greater stride-to-stride variability than younger participants. Associations between measures of static and dynamic postural control were found only under the single-task condition in the elderly.
  
  
  CONCLUSIONS
  Age-related deficits in the postural control system seem to be primarily responsible for the observed results. The weak correlations detected between static and dynamic measures could indicate that fall-risk assessment should incorporate dynamic measures under multi-task conditions, and that skills like erect standing and walking are independent of each other and may have to be trained complementarily.
authors.affiliation: Institute of Exercise and Health Sciences, University of Basel, Basel, Switzerland. urs.granacher @ unibas.ch
authors.forename: Urs
authors.initials: U
authors.lastname: Granacher
authors.forename: Stephanie A
authors.initials: SA
authors.lastname: Bridenbaugh
authors.forename: Thomas
authors.initials: T
authors.lastname: Muehlbauer
authors.forename: Anja
authors.initials: A
authors.lastname: Wehrle
authors.forename: Reto W
authors.initials: RW
authors.lastname: Kressig
mesh_terms: D000058:Accidental Falls / Q000517:prevention & control; D000328:Adult; D000368:Aged; D000375:Aging / Q000502:physiology*; D003071:Cognition / Q000502:physiology; D005684:Gait / Q000502:physiology; D006801:Humans; D008609:Mental Status Schedule; D004856:Postural Balance / Q000502:physiology*; D018570:Risk Assessment; D013647:Task Performance and Analysis; D016138:Walking / Q000502:physiology; D055815:Young Adult