Effects Of Yoga On Heart Rate Variability And Arterial Stiffness: A Systematic Review With Meta-analysis

PURPOSE: To estimate the effects of yoga interventions on measures of heart rate variability and arterial stiffness. METHODS: PubMed, Scopus, and CINAHL were searched from inception through January 17, 2025. We included experimental trials with no intervention comparison groups that examined the effects of yoga (≥4 weeks) involving physical poses on arterial stiffness or heart rate variability outcomes in adults. Effect sizes were classified as small (<0.20), medium (0.20 to 0.79), and large (≥0.80). RESULTS: Thirty-seven trials (N=4,206) were included. Pooled results showed yoga significantly improved standard deviation of normal-to-normal intervals (SDNN n=1,298, SMD=0.68, 95% CI=0.39 to 0.98, p<0.001), root mean square of successive differences (RMSSD n=1,439, SMD=0.66, 95% CI=0.41 to 0.91, p<0.001) and pulse pressure (n=705, SMD=-0.35, 95% CI=-0.69 to -0.01, p=0.042). The pooled effects of yoga were not significant for carotid-femoral pulse wave velocity (PWV n=276, SMD=-0.50, 95% CI=-1.20 to 0.19, p=0.16), brachial-ankle PWV (n=275, SMD=-0.60, 95% CI=-1.27 to 0.07, p=0.079), brachial arterial stiffness index (n=202, SMD=-0.71, 95% CI=-3.01 to 1.60, p=0.548), ankle arterial stiffness index (n=202, SMD=-0.72, 95% CI=-1.60 to 0.20, p=0.123), and augmentation index (n= 87, SMD=0.13, 95% CI=-0.48 to 0.74, p=0.674). CONCLUSIONS: Yoga improved SDDN, RMSSD, and pulse pressure, with no association observed for any other measures of arterial stiffness. Few studies and small samples for most arterial stiffness outcomes limit firm conclusions, justifying the need for large, fully-powered trials to clarify yoga’s impact.