The effect on the self-selected gait velocity caused by the subjects’ position when walking on a self-paced dual-belt treadmill in a virtual reality environment while performing a color-word Stroop task: a pilot study

Background: When people walk while performing a cognitive dual-task, a decrease in gait velocity will occur because of the demand for some of the same cognitive resources. However, in a previous study they found an increase instead of a decrease in gait velocity when subjects walked on a self-paced treadmill while performing a color-word Stroop task. Aim: The aim of this study was to determine if the increase found in gait velocity in the previous study was a consequence of the subjects’ position. Additionally, it was investigated whether real-time feedback about the subjects’ position could substitute the lack of a reference point. Method: Position and gait velocity was measured in twelve healthy subjects during a trial consisting of eight control conditions and eight different interventions. Results: A significant difference was found in gait velocity between the interventions where the accelerations-line was moved furthest to the front and back (IzerolineA, IzerolineB) and in position between the original intervention and one with a neutral zone (Iorginal1, Ineutralzone). No differences were found in position or velocity with any of the feedback systems. Conclusion: From the results it could be concluded that the increase in gait velocity was a consequence of the subjects positioning themselves further in the forward direction on the treadmill. No conclusions could be drawn with the feedback systems