title: Age-related differences in dual task walking: a cross sectional study.
abstract: BACKGROUND
  Variability in stride velocity during walking characterizes gait instability and predicts falling in older individuals. Walking while executing a cognitive task is also associated with increased risk of falling, particularly in older adults. Variability in stride velocity, particularly during dual task walking conditions, may differ between younger and older individuals. The purpose of this study was to examine whether gait velocity and variability in stride velocity differ between older community-dwelling women and younger women during dual task walking.
  
  
  METHODS
  Twenty-three older (80 +/- 9 years) and 19 younger (23 +/- 2 years) women walked under each of two conditions: (1) walking at a self-selected velocity and (2) walking at a self-selected velocity while incrementally counting backwards. Gait velocity and variability in stride velocity were measured with GAITRite instrumentation.
  
  
  RESULTS
  Gait velocity decreased and variability in stride variability increased, in both groups, during dual task walking. The relative reduction in gait velocity and the magnitude of variability in stride velocity were greater in the older subjects than younger subjects.
  
  
  CONCLUSIONS
  The gait changes observed in dual task walking characterize reduced gait stability and indicate that cognitively demanding tasks during walking have a destabilizing effect on gait that may place older persons at greater risk of falls.
authors.affiliation: Program in Physical Therapy, Mayo Clinic, Rochester, MN, USA. andrew.priest@clarke.edu
authors.forename: Andrew W
authors.initials: AW
authors.lastname: Priest
authors.forename: Kathleen B
authors.initials: KB
authors.lastname: Salamon
authors.forename: John H
authors.initials: JH
authors.lastname: Hollman
mesh_terms: D000058:Accidental Falls / Q000517:prevention & control; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D001288:Attention / Q000502:physiology*; D003071:Cognition / Q000502:physiology*; D003430:Cross-Sectional Studies; D004185:Disability Evaluation; D017079:Exercise Tolerance / Q000502:physiology; D005260:Female; D005684:Gait / Q000502:physiology; D020233:Gait Disorders, Neurologic / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology*; D006801:Humans; D009483:Neuropsychological Tests; D004856:Postural Balance / Q000502:physiology; D011597:Psychomotor Performance / Q000502:physiology*; D012021:Reflex, Abnormal / Q000502:physiology; D016138:Walking / Q000502:physiology*; D055815:Young Adult