PT - JOURNAL ARTICLE AU - Rosenblum, Uri AU - Lavi, Adi AU - Fischer, Arielle AU - Parmet, Yisrael AU - Haim, Amir AU - Handelzalts, Shirley TI - The Effect of Arm Restriction on Dynamic Stability and Upper Body Responses to Lateral Loss of Balance During Walking: An Observational Study AID - 10.1101/2023.09.11.557158 DP - 2024 Jan 01 TA - bioRxiv PG - 2023.09.11.557158 4099 - http://biorxiv.org/content/early/2024/07/08/2023.09.11.557158.short 4100 - http://biorxiv.org/content/early/2024/07/08/2023.09.11.557158.full AB - 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.Competing Interest StatementThe authors have declared no competing interest.