Virtual Reality-Based Green Exercise and State Anxiety in University Students: A Scoping Review and Psychophysiological Framework

Virtual reality (VR)-based green exercise combines actual physical activity with exposure to digitally simulated natural environments, but evidence concerning state anxiety in university students remains limited. This scoping review mapped relevant empirical and secondary evidence, identified research gaps, and examined candidate psychophysiological measures, particularly heart rate variability (HRV) and functional near-infrared spectroscopy (fNIRS). Web of Science Core Collection, Scopus, and PubMed were searched, followed by a targeted supplementary search during revision. After report-level reconciliation, 346 eligible reports were retained, comprising 306 primary empirical reports and 40 secondary evidence reports. A retrospective report-level audit applying four operational criteria identified one Direct-core report and eight Near-core reports among the 306 retained primary empirical reports. Targeted source verification confirmed HRV measurements in at least 30 retained primary empirical reports and identified one fNIRS-positive report. These findings represent confirmed positive cases rather than exhaustive prevalence estimates across all 306 reports. Although directly aligned evidence was identified, it remains insufficient to establish consistent effects of VR-based green exercise on state anxiety in university students or to validate an integrated autonomic–prefrontal mechanism. A hypothesis-generating 2 × 2 experimental framework is proposed to guide future controlled research.