Slow Frequency Anuloma Viloma Pranayama Modulates Cardiac and Neural Oscillations in Yoga Practitioners

Anuloma viloma pranayama (AVP) also known as Alternate nostril breathing (ANB) is the most commonly used form of pranayama, the ancient breath control practice. It is known to modulate cardiovascular control and brain activity. This study analysed the simultaneous recording of Heart rate variability (HRV) and brain activity during and after AVP at a very slow frequency. We carried out an observational cohort study from October 2021 to December 2021 with purposive sample of 30 (Thirty) healthy volunteers involved in regular kriya yoga practice for the last 15 years were inducted into this study AVP involves slow and deep inhalation through one nostril at a time. The ECG for HRV analysis and spectrum of EEG waves were recorded throughout the pre-AVP, during-AVP and post-AVP (each of five-minute duration). The parameters were compared and analysed by repeated measures of analysis of variance with post-hoc analysis using Bonferroni and Holm's multiple comparisons. In time Domain parameters, SDNN and RMSSD were significantly higher during AVP as compared to the pre-AVP and post AVP. In frequency domain parameters total power, LF power, HF power, showed a significant increase during AVP, LF/HF ratio increased during AVP and remained higher post-AVP also. Similarly, Alpha, Beta and Gamma wave power increased significantly during AVP as compared to pre-AVP and post-AVP. The lungs-heart-brain act as coupled oscillators, the analysed data show an increased arousal, attentive and focused state with a negligible change in the heart rate. An overall increased variability in HRV was recorded.