Exercise Responses During Outdoor Versus Virtual Reality Indoor Arm+FES-Leg Cycling in Individuals with Spinal Cord Injury.

Virtual reality (VR)-enhanced indoor hybrid cycling in people with spinal cord injury (SCI) can be comparable to outdoor hybrid cycling. Eight individuals with chronic thoracic-lesion SCI performed voluntary arm and electrically assisted leg cycling on a hybrid recumbent tricycle. Exercises were conducted outdoors and indoors incorporating VR technology in which the outdoor environment was simulated on a large flat screen monitor. Electrical stimulation was applied bilaterally to the leg muscle groups. Oxygen uptake (VO), heart rate, energy expenditures, and Ratings of Perceived Exertion were measured over a 30-minute outdoor test course that was also VR-simulated indoors. Immediately after each exercise, participants completed questionnaires to document their perceptual-psychological responses. Mean 30-minute VO was higher for indoor VR exercise (average VO-indoor VR-exercise: 1316 ± mL/min vs. outdoor cycling: 1255 ± 53 mL/min; highest VO-indoor VR-exercise: 1615 ± 67 mL/min vs. outdoor cycling: 1725 ± 67 mL/min). Arm and leg activity counts were significantly higher during indoor VR-assisted hybrid functional electrical stimulation (FES) cycling than outdoors; 42% greater for the arms and 23% higher for the legs ( < 0.05). Similar responses were reported for exercise effort and perceptual-psychological outcomes during both modes. This study proposes that combining FES and VR technology provides new opportunities for physical activity promotion or exercise rehabilitation in the SCI population, since these modes have similar "dose-potency" and self-perceived effort. Human Research Ethics Committee of the University of Sydney Ref. No. 01-2010/12385.