Effects of a Passive Back Support Exoskeleton on Balance While Walking

Passive back support exoskeletons (PBSEs) have been promoted as a means of alleviating the physical strain associated with manual tasks in industrial settings. These devices are known to influence the wearer's kinematics, muscle activation, and balance. Slips and trips, which are frequent precursors to falls, often occur during construction tasks. The effects of PBSEs on balance and the ability to recover from slip- and trip-like perturbations during walking have not been thoroughly examined. The present study aimed to investigate the effects of a PBSE on ground reaction forces (GRF) after slip and trip-like perturbations during walking on an instrumented treadmill. Nine male participants walked on an instrumented treadmill under two conditions: without wearing a PBSE (WOE) and after wearing a PBSE (WE). Each participant experienced normal walking, slip, and trip events, presented in a random order. GRFs were recorded using a force plate integrated into the treadmill. Fx (force in the mediolateral direction) was higher (p = 0.003) in WE (mean, 166.32 N) than in WOE (mean, 140.52 N) by 18.36 % after slip perturbations. Fy (force in the anteroposterior direction), Fz (force in the vertical direction), and Fr (the resultant force) did not show statistically significant differences between WE and WOE after slip perturbations. Following trip perturbations, a statistically significant increase was observed in Fz (p<0.001) and Fr (p<0.001). Fz and Fr were higher in WE than WOE by 25.24 % and 8.88 %, respectively. Wearing a PBSE may alter the GRF in a mediolateral or vertical direction that may predispose the wearer to fall. Construction workers should be provided with balance training while wearing a PBSE and then exercise caution while walking on a construction site.