It is well known that physical activity levels for persons after stroke or acquired brain injuries do not reach existing recommendations. Walking training is highly important since the ability to walk is considered to be a meaningful occupation for most people, and is often reduced after a brain injury. This suggests a need to innovate stroke rehabilitation, so that forms of walking training that are user-friendly and enjoyable can be provided.
An interview study was carried out with persons after stroke (n = 8), or acquired brain injury (n = 2) at a rehabilitation unit at Sahlgrenska University Hospital. We used a semi-structured interview guide to investigate experiences and thoughts about walking on a treadmill with non-immersive virtual reality feedback. The contents were analyzed through an inductive approach, using qualitative content analysis.
The virtual reality experience was perceived as enjoyable, exciting, and challenging. Participants stressed that the visual and auditory feedback increased their motivation to walk on a treadmill. However, for some participants, the virtual reality experience was too challenging, and extreme tiredness or fatigue were reported after the walking session.
Participants’ thoughts and experiences indicated that the Virtual Reality walking system could serve as a complement to more traditional forms of walking training. Early after a brain injury, virtual reality could be a way to train the ability to handle individually adapted multisensory input while walking. Obvious benefits were that participants perceived it as engaging and exciting.
In general, physical activity levels in rehabilitation units are low  and do not reach the recommendations for persons with stroke or acquired brain injury (ABI) . There are also indications that the intensity of physiotherapy sessions after stroke is mostly at low levels . Several barriers may contribute to inactivity, such as neurological deficits, cognitive impairment, environmental factors, and lack of motivation [4, 5].
A dose-response effect on exercise outcome after stroke has been shown, and training should be highly repetitive and task oriented . Walking training is important and considered to be a meaningful occupation for most people. To increase walking exercise intensity, treadmill walking has been proposed as a means of task-oriented training that gives the opportunity for many repetitions, and has shown to promote a more normal walking pattern . Walking on a moving surface like a treadmill is more demanding than walking on the ground in terms of sensory processing, postural control and movement coordination. From a motivational perspective, treadmill walking may be perceived as boring the long run.
Training of goal-specific activities with a high number of repetitions may be offered using virtual reality (VR) applications, which have been introduced in neurological rehabilitation [8, 9]. Training using VR has also been suggested to enhance neuroplasticity after stroke  by means of offering multisensory stimulation at a high intensity. VR comprises computer-based real-time simulation of an environment with user interaction  visually displayed on a screen or through head-mounted devices. Differences in technology and visual presentations in 2D or 3D enable varying types of feedback, levels of immersion and sense of presence in the virtual environment [9, 11]. VR feedback can be mediated through vision, hearing, touch, movement, or smell. The technique provides performance feedback–both directly experienced and objectively quantified, and may thereby increase exercise motivation, and improve motor performance [12–14].
Following stroke, VR training has been mostly described for the upper limb but also for the lower limb; balance and walking as well as for perceptual/cognitive skills . VR has shown a potential for positive effects on walking and balance abilities, although the number of studies are low and the evidence for its superiority to other methods is low [8, 15, 16].
Although few adverse events from VR training have been described, some participants have reported headache or dizziness  and knowledge is lacking regarding how persons affected by brain injuries perceive the exposure of multisensory input, during a complex activity such as treadmill walking with VR. The potential effects on motivation and participant experience of VR are scarcely investigated  and mostly focused on upper limb activities and games . Based on this, we wanted to investigate patients’ overall experiences of a VR concept in walking training.
The aim of the present study was to explore the experiences of VR in addition to walking on a treadmill in persons with stroke or acquired brain injuries. Participants’ overall experiences and suggestions for development of the exercise method were areas of interest.[…]