Gait differences in overground walking between real and immersive virtual environments

Purpose Increasing evidence has shown the benefit of virtual reality (VR) based gait training and physical rehabilitation for various movement related disorders. Usage of non-immersive VR and treadmills in past research has shown conflicting results with work that uses immersive VR and overground walking. Important aspects of gait such as variability are also scarce in research comparing gait in VR and non-VR environments. This study aimed to investigate the influence of an immersive VR environment on overground gait whilst also measuring the impact of VR on gait variability. Methods Twelve young healthy adults were tasked with walking across a 6m carpet in both real lab and virtual lab environments. The virtual lab environment was designed to replicate the real lab environment. Participants wore a HMD during walking and were given time to familiarize themselves with the VR lab prior to data collection. In a counterbalanced design, participants completed 20 passes in both the virtual environment and real-life environment totalling a 120m of walking in both environments. Paired t-tests and Pearson’s correlations were used to evaluate differences in gait between the two environments. Results Greater cadence, step length, and velocity were observed in the real environment compared to the virtual environment. Greater double stance time (%), step time, and step width variability (%CV) were observed in the virtual environment. Moderate-to-strong correlations were observed in gait parameters between the environments. Conclusion The immersive VR environment showed a slower more cautious gait compared to the real environment. However, overall gait behavior is still maintained in the virtual environment, such that fast walks in the real environment continue to be fast in the virtual environment and vice versa. The absence of visual feedback of limbs could contribute to these results and future work should investigate how incorporating feedback may influence these differences in gait.