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bioRxiv · 10.1101/333989

Exposure to unpredictable trips and slips while walking can improve balance recovery responses with minimum predictive gait alterations

Abstract

INTRODUCTIONThis study aimed to determine if repeated exposure to unpredictable trips and slips while walking can improve balance recovery responses when predictive gait alterations (e.g. slowing down) are minimised.\n\nMETHODSTen young adults walked on a 10-m walkway that induced slips and trips in fixed and random locations. Participants were exposed to a total of 12 slips, 12 trips and 6 non-perturbed walks in three conditions: 1) right leg fixed location, 2) left leg fixed location and 3) random leg and location. Kinematics during non-perturbed walks and previous and recovery steps were analysed.\n\nRESULTSThroughout the three conditions, participants walked with similar gait speed, step length and cadence(p>0.05). Participants extrapolated centre of mass (XCoM) was anteriorly shifted immediately before slips at the fixed location (p<0.01), but this predictive gait alteration did not transfer to random perturbation locations. Improved balance recovery from trips in the random location was indicated by increased margin of stability and step length during recovery steps (p<0.05). Changes in balance recovery from slips in the random location was shown by reduced backward XCoM displacement and reduced slip speed during recovery steps (p<0.05).\n\nCONCLUSIONSEven in the absence of most predictive gait alterations, balance recovery responses to trips and slips were improved through exposure to repeated unpredictable perturbations. A common predictive gait alteration to lean forward immediately before a slip was not useful when the perturbation location was unpredictable. Training balance recovery with unpredictable perturbations may be beneficial to fall avoidance in everyday life.

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Okubo, Y., Brodie, M. A., Sturnieks, D. L., Hicks, C., Carter, H., Toson, B., Lord, S. R.. 2018-06-04. Exposure to unpredictable trips and slips while walking can improve balance recovery responses with minimum predictive gait alterations. https://doi.org/10.1101/333989

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