Self-Administered Yoga Facial Massage with Breathing Regulation to Improve Heart Rate Variability in Individuals with Computer Vision Syndrome: A Randomized Controlled Trial.

Aim: This study is based on a registered trial (TCTR20241119007), in which the primary outcome was visual fatigue. The current study aims to evaluate the effects of specialized Thai yoga facial massage (STYFM) on heart rate variability (HRV) as a physiological marker associated with autonomic regulation. Methods: This two-arm randomized controlled trial was conducted at Khon Kaen University, Thailand, from January to February 2025. Thirty-two individuals with computer vision syndrome were randomly assigned to receive either a 4-week program of self-administered STYFM or eyes-closed seated rest under identical conditions without tactile or auditory stimulation. Each session lasted 10 to 15 min and took place 10 times per week. Physiological parameters, including HRV, heart rate (HR), and peripheral oxygen saturation (SpO₂), were assessed at the baseline, mid-intervention, and post-intervention. Data were analyzed using linear mixed models with Bonferroni correction. Results: The STYFM intervention significantly improved autonomic regulation compared to the control group. Participants in the STYFM group showed notable increases in HRV parameters, including the standard deviation of normal-to-normal intervals (p < 0.001), root mean square of successive differences (p < 0.001), the percentage of successive RR intervals differing by more than 50 ms (p < 0.001), total power (p = 0.004), low-frequency power (LF, p = 0.049), and high-frequency power (HF, p < 0.001). The LF/HF ratio decreased but was not statistically significant (p = 0.194). Additionally, the STYFM group demonstrated significantly higher peripheral oxygen saturation (p < 0.001) and reduced HR (p < 0.001), with no adverse events reported. Conclusion: This analysis suggests that STYFM significantly improved HRV, increased SpO2, and reduced HR, indicating enhanced parasympathetic modulation and improved autonomic regulation. Since this study represents a preliminary study of a larger clinical trial, it is important to note that the outcome data for the registered primary endpoint (visual fatigue score) will be reported in a separate publication.