Neurophysiological and subjective responses to a virtual downhill cycling exercise

Purpose ̶ Downhill parts of a cycling race are among the most complex and therefore the most stressful elements for cyclists. Virtual Reality (VR) is thus an interesting tool to monitor reactions to such situations, in safe environment. The present exploratory study aimed to measure physiological and subjective stress during a virtually-simulated downhill race, according to the degree of realism of the simulation. Methods ̶ Eighteen young, healthy participants were divided into two groups according to their experience in cycling: high-level amateur cyclists (Cyclists; 9.7 ± 2.5 weekly hours of training) and non-cyclists (Controls). They randomly performed 4 different conditions of passive immersion, by manipulating the position (sitting, SIT; on reclined Cycle Ergometer, ERG), with (VR) or without immersion (SCREEN), each time visualizing a virtual 5-minute downhill cycling race from a personal point of view. Physiological stress responses were monitored with upper limb muscle activity (Electromyographic, EMG), electrodermal (Galvanic Skin Response, GSR) and heart activity (Electro-CardioGraphy, ECG). Subjective sensations of fear and cybersickness were assessed using visual analog scales. Results ̶ VR had higher effects than SCREEN on all markers, with more pronounced effects in CONTROLS. Despite overall lower EMG activity than CONTROLS, CYCLISTS exhibited more muscle tension under VR on the trapezius. ERG conditions showed higher stress responses than SIT. Conclusion ̶ These results demonstrate that VR induces psychophysiological stress which increases with the simulation’s realism (from incongruent to congruent posture, for instance). CYCLISTS were only sensitive to VR with the highest level of realism, i.e. during VR-ERG