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bioRxiv · 10.1101/2023.09.11.557158

The Effect of Arm Restriction on Dynamic Stability and Upper Body Responses to Lateral Loss of Balance During Walking: An Observational Study

Rosenblum, U.·Lavi, A.·Fischer, A.·Parmet, Y.·Haim, A.·Handelzalts, S.
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Abstract

When losing balance, upper-body movements serve as mechanical aids to regain stability. However, it remains unclear how these movements contribute to dynamic stability during recovery from a lateral loss of balance while walking with arm restriction. We aimed to 1) quantify the effect of arm restriction on gait stability and upper-body velocities, and 2) characterize upper-body kinematic strategies in response to lateral surface translations under different arm restriction conditions. Healthy adults were exposed to lateral surface translations while walking on a computerized treadmill under three conditions: free arms, 1-arm restricted and, 2-arms restricted. Dynamic stability and upper-body velocities for the first step after perturbation onset were extracted. We found decreased dynamic stability in the sagittal plane and increased trunk velocity in the 2-arm restricted condition compared to the free arms condition. Head and trunk movements in the mediolateral plane were in opposite directions in 44.31% of responses. Additionally, significant trunk velocities were observed in the opposite direction to the perturbation-induced loss of balance. Our results support the contribution of increased upper-body velocities to balance responses following arm-restricted walking perturbations and suggest that the 2-arm restricted condition may be utilized as a perturbation-based balance training, focusing on head and trunk responses.

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Rosenblum, U., Lavi, A., Fischer, A., Parmet, Y., Haim, A., Handelzalts, S.. 2023-09-13. The Effect of Arm Restriction on Dynamic Stability and Upper Body Responses to Lateral Loss of Balance During Walking: An Observational Study. https://doi.org/10.1101/2023.09.11.557158

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