Variability of stride length with walking speed in free living conditions
Jennyfer Ross, Sebastien Chastin
Glasgow Caledonian University Glasgow G4 1OB
Background & Aim: Walking is a voluntary task that appears to be relatively stable from one step to the next. Studies over the past two decades have revealed the time between consecutive steps, at any instant, is related to or dependent upon previous steps in healthy adults. In disease and ageing populations the time between consecutive steps becomes unpredictable. Neurologically diseased and ageing populations generally walk at a slower walking pace than young healthy adults, and as such could act as a potential confounding variable in gait analysis studies. This study’s purpose was to determine the effect three different over-ground walking speeds could have on the variation of consecutive stride interval times. Methods: A convenience sample of 15 young healthy adults were recruited and the stride interval times of consecutive steps were measured for both legs during 8-10 minutes of slow, normal and fast over-ground walking using the activPALTM activity monitor. The mean variation between consecutive stride intervals was calculated at each speed to determine the relationship between mean stride interval variation and real life over-ground walking speed. Results: The mean variation of consecutive stride intervals increased with increasing speed. A significant difference was found between slow and fast walking speeds as well as normal and fast walking speeds (p-value <0.001). Conclusions: There is a significant relationship between walking speed and mean stride interval variation of consecutive steps. Further to this, stride interval times at faster walking speeds appear to be more unpredictable than at slower walking speeds.
References
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