Effects of dual task on turning ability in stroke survivors and older adults

- We examine stepping patterns during turning in stroke survivors and older adults.
- We examine changes in stepping during turning in single and dual task conditions.
- Identifying dual task decrements to turning can help identify mechanisms of falls.
- Single support phase was found to be increased when distracted in both groups.
- Increased single support duration may be a cause of falling when distracted.

BackgroundTurning is an integral component of independent mobility in which stroke survivors frequently fall.ObjectiveThis 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.MethodsWalking and turning (90°) was assessed under single (walking and turning alone) and dual task (subtracting serial 3 s 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).ResultsBoth 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.ConclusionsIncreased 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.