Wearing an Arm Support Exoskeleton Does Not Affect Balance but May Decrease Dynamic Stability During a Step-Down Maneuver.

Abstract

ObjectiveAssess the effects of arm support exoskeletons (ASEs) on dynamic balance during dynamic tasks.BackgroundASEs can reduce muscle activation during labor-intensive tasks, potentially alleviating fatigue, discomfort, and injury risk. However, implications on worker safety, particularly regarding altered balance, remain a concern.MethodsWe evaluated the effects of three different ASEs on dynamic balance using postural sway parameters and the dynamic postural stability index (DPSI). Twenty-three healthy volunteers (7 F) performed a single-leg, step-down maneuver with and without ASEs.ResultsSway did not differ substantially across conditions, except for a slight increase in sway area in one comparison (18.3%, η_p²≈0.07). In contrast, DPSI increased in all ASE conditions compared to no-ASE (6.1-10.1%, η_p²≈0.05-0.10). A main effect of sex was found for sway and dynamic stability metrics, with females exhibiting greater postural excursions (13.5% higher sway and 9.3% higher DPSI on average, η_p² up to 0.24). Height and body mass were negatively correlated with sway and DPSI parameters, suggesting a potential role of individual anthropometrics in modulating balance performance.ConclusionASEs do not impair balance during dynamic tasks such as a step-down maneuver and single-leg stance, but they may affect stabilization strategies, especially for individuals with low body mass and height.ApplicationThese findings support the potential for a cautious integration of ASEs in industrial settings, as these devices appear to have a minimal impact on balance during moderately dynamic tasks, but observed differences in DPSI highlight the need for careful evaluation in specific populations.