title: Effects of dual task on turning ability in stroke survivors and older adults.
abstract: BACKGROUND
  Turning is an integral component of independent mobility in which stroke survivors frequently fall.
  
  
  OBJECTIVE
  This study sought to measure the effects of competing cognitive demands on the stepping patterns of stroke survivors, compared to healthy age-match adults, during turning as a putative mechanism for falls.
  
  
  METHODS
  Walking and turning (90°) was assessed under single (walking and turning alone) and dual task (subtracting serial 3s while walking and turning) conditions using an electronic, pressure-sensitive walkway. Dependent measures were time to turn, variability in time to turn, step length, step width and single support time during three steps of the turn. Turning ability in single and dual task conditions was compared between stroke survivors (n=17, mean ± SD: 59 ± 113 months post-stroke, 64 ± 10 years of age) and age-matched healthy counterparts (n=15).
  
  
  RESULTS
  Both groups took longer, were more variable, tended to widen the second step and, crucially, increased single support time on the inside leg of the turn while turning and distracted.
  
  
  CONCLUSIONS
  Increased single support time during turning may represent biomechanical mechanism, within stepping patterns of turning under distraction, for increased risk of falls for both stroke survivors and older adults.
authors.affiliation: School of Health Sciences, University of Salford, Manchester, UK. Electronic address: k.hollands@salford.ac.uk.
authors.forename: K L
authors.initials: KL
authors.lastname: Hollands
authors.affiliation: School of Health Sciences, University of Salford, Manchester, UK.
authors.forename: D
authors.initials: D
authors.lastname: Agnihotri
authors.affiliation: Stroke & Vascular Research Centre, School of Nursing, Midwifery & Social Work, University of Manchester, UK.
authors.forename: S F
authors.initials: SF
authors.lastname: Tyson
mesh_terms: D000058:Accidental Falls; D000368:Aged; D000369:Aged, 80 and over; D001696:Biomechanical Phenomena / Q000502:physiology; D016022:Case-Control Studies; D005260:Female; D020233:Gait Disorders, Neurologic / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D051346:Mobility Limitation; D011312:Pressure; D012307:Risk Factors; D020521:Stroke / Q000503:physiopathology* / Q000523:psychology; D017741:Survivors; D013647:Task Performance and Analysis; D013997:Time Factors
keywords: Dual-task; Falls; Gait; Stroke; Turning