Resting heart rate variability in regular yoga practitioners - A cross-sectional study

Heart rate variability (HRV) is a useful and powerful non-invasive tool for quantitative assessment of cardiac autonomic function. Recent studies have shown that low heart rate variability is an indication of increased risk for cardiac diseases and sudden cardiac death. Yoga has been associated with improved cardio-respiratory performance. Thirty male regular yoga practitioners doing yoga for more than 3 years, age between 25-45 years (yoga group) and 30 male non-yoga practitioners, age-matched (control group) were included. A computerized Niviqure ECG system with HRV software was used for heart rate variability recording. Our results show that frequency-domain parameters like LF power, LF n.u, and LF/HF ratio were significantly lower in yoga group compared to control group. Time-domain parameters like mean RR, NN50, pNN50 were significantly higher in yoga group compared to control group. We conclude that the yoga increases heart rate variability by optimizing the autonomic functions, which is a good indicator of cardiac autonomic activity during rest.