## 4 Discussion
clinically relevant variables, as well as its advantages over conventional physical therapy--such as increased enjoyment, motivation, and enhanced sensory feedback [54]. In the context of chronic pain management, the proposed mechanisms underlying the effects of VR include distraction, attentional engagement, and multisensory stimulation [30; 55]. These mechanisms are thought to immerse the patient in a virtual environment, potentially leading to improvements in PI, PPTs, psychological factors (kinesiophobia, catastrophizing), and even temporal summation over the medium term [29]. Functional magnetic resonance imaging studies suggest that VR stimulates the insular and sensory cortices in ways comparable to opioids and may modulate pain perception through pathways that reduce conscious awareness of pain, potentially altering the behavior of the pain modulation system to decrease pain sensitivity [56; 57]. However, given the exploratory nature of our study, caution is warranted in drawing definitive conclusions. Our findings reflect only the responses observed in a small sample and should not be generalized to the broader population. The response to iVRE appears to be complex and variable, as demonstrated by the contrasting trends observed between PI and PPTs following both a single session and the complete iVRE protocol. These findings underscore the complex nature of pain modulation in FM and highlight the need for further high-quality research to clarify the underlying mechanisms. In our study, the iVRE intervention resulted in an observed improvement in the sample's perceived PI. This finding aligns with a recent review focusing on the effects of VR-based exercise therapy in patients with chronic pain, which concluded that various VR modalities can reduce PI in this population [29]. However, that review did not specifically include iVRE interventions for patients with FM. A previous review focusing exclusively on FM patients [25], identified only one study that utilized an iVRE protocol [31]. In that study, [PERSON] et al. reported a significant decrease in PI, measured using a visual analogue scale, and attributed the results to reduced fear of movement and increased adherence due to the high level of engagement associated with VR. However, [PERSON] et al. did not explore the underlying analgesic mechanisms driving their patients' pain responses, nor did they stratify participants according to baseline prognostic risk. Our study aimed to explore changes in PI, MPS, and exercise-induced hypoalgesia mechanisms following a 6-week iVRE program and examined how PI varied according to baseline risk in a sample of FM patients--an aspect not previously investigated. It is important to note that our findings are based on a small, uncontrolled sample and should not be extrapolated to the broader population. Nonetheless, these results provide a foundation for future controlled studies with larger samples to replicate this protocol and observe its effects on the studied variables. Such studies could enable a more in-depth analysis with stronger evidence to address current gaps in the literature, including the integration of innovative AI technologies for pain assessment [58]. Several studies have described the involvement of psychological variables as factors that can influence the perception of PI in individuals with FM [59; 60]. In this context, therapeutic interventions using various modalities of VR have shown positive effects on pain-related outcomes in people with chronic pain and FM--particularly when integrated with other treatments that address the psychological aspects that influence PI [44; 61]. In such cases, the improvements observed may result from the direct influence of VR on cognitive, emotional, and motivational factors [27; 62; 63]. However, its effect on the underlying analgesic mechanisms has not yet been clearly described.