Investigation into the Effects of Virtual Reality and Electrical Muscle Stimulation on Mood, Exertion and Muscular Fatigue

The physiological and psychological effects of the Valkyrie EIR system, which combines virtual reality, gamification, and electrical muscle stimulation (EMS), were investigated. A within-subjects design was used, 26 participants took part in two research sessions, one involving a Valkyrie class with EMS and another without. Physiological measures, including heart rate, pressure sensitivity of the biceps and triceps, and delayed onset of muscular soreness (DOMS) were assessed alongside psychological measures, including questionnaires regarding participant experience and mood, as well as rate of perceived exertion (RPE). Mood significantly increased post-Valkyrie classes, which were deemed enjoyable and fun, with 88.5% of participants favouring the EMS condition due to increased immersion, intensity and challenge. Significant differences were found between the EMS and control conditions, including higher RPE scores, greater DOMS and a higher heart rate, when taking into consideration the interactions of variables. These results show that the EMS induced a higher intensity of exercise, with the potential for greater muscular adaptation. Overall, Valkyrie EIR with EMS was shown to be a promising approach for enhancing exercise intensity in VR whilst encouraging participant engagement.