Effects of conventional versus virtual reality-simulated treadmill exercise on fatigue, cognitive function, and participant satisfaction in post-COVID-19 subjects. A randomized trial.

Background/objective: Post-COVID-19 subjects typically experience symptoms of fatigue, cognitive impairment, and sleep difficulty, which can be relieved by conventional aerobic exercise. Virtual Reality (VR) technology to support conventional exercise has recently gained much attention. Therefore, this study aimed to assess the effects of traditional treadmill exercise compared to virtual reality-simulated treadmill exercise on fatigue, cognitive function, sleep quality, and participant satisfaction with the exercise program in post-COVID-19 subjects.

Methods: This single-centered, randomized, parallel-group intervention study was conducted between December 2021 and March 2022. Sixteen of twenty post-COVID-19 subjects completed this study (n1 = 8, n2 = 8). Inclusion criteria were persistent dyspnea/fatigue, mild cognitive problems, and age from 3060 years. Exclusion criteria were previous severe COVID-19 infection and ICU admission, concomitant respiratory or cardiovascular disease, and musculoskeletal or neurological disease. Eligible subjects were assigned randomly to two groups: a non-VR group that received traditional treadmill aerobic exercise only and a VR group that received treadmill exercise with non-immersive VR. Both groups received moderate-intensity exercise on a treadmill at [5060 % (peak HR－resting HR) + resting HR] for 3045 min, three times per week, and for four weeks. The outcome measures were the Chalder Fatigue Scale, Montreal Cognitive Assessment (MoCA) questionnaire, Pittsburgh Sleep Quality Index (PSQI), and participant satisfaction with the exercise program rated on a 5-point Likert scale.

Results: Both groups showed significant improvements in the Chalder Fatigue Scale, the MoCA questionnaire, and the PSQI scores after training compared to baseline (p < 0.05), without significant differences between them (p > 0.05). However, participant satisfaction with the exercise program was significantly higher in the VR group than in the non-VR group (p = 0.037).

Conclusion: A moderate-intensity 4-week treadmill exercise program with and without non-immersive VR may improve fatigue, cognitive function, and sleep quality to the same extent in COVID-19 survivors. However, participant satisfaction with the exercise program could be greater after conventional treadmill training assisted by non-immersive VR than after conventional treadmill training alone in this cohort.

Trial Registration: Pan African Clinical Trials Registry, PACTR202311561948428, retrospectively registered.