Document Type : Original Article

Authors

• . Varun Malhotra ¹
• . Ragini Srivastava ¹
• . Poovarasan Parasuraman ¹
• . Danish Javed ²
• . Santosh Wakode ¹
• . Avinash Thakare ¹
• . Ananyan Sampath ³
• . Ankita Kumari ³

¹ Department of Physiology, AIIMS, Bhopal, India

² AYUSH, AIIMS, Bhopal, India

³ Undergraduate MBBS Students, AIIMS, Bhopal, India

Abstract

BACKGROUND: The ancient Indian science of Yoga makes use of voluntary regulation of breathing
to make respiration rhythmic and calm the mind. This practice is called pranayama. Nadisuddhi
pranayama means “purification of subtle energy paths,” inhalation and exhalation are through
alternative nostrils for successive respiratory cycles. Surya Anuloma‑Viloma pranayama means “heat
generating breathing particle” when the respiratory cycle of inhalation and exhalation is completed
through the right nostril exclusively. When completed through the left nostril alone, the practice is
called “Chandra Anuloma‑Viloma pranayama,” which means a heat‑dissipating or cooling liberating
practice. We compared the effect of right nostril breathing (RNA) and left nostril breathing (LNB)
pranayama on heart rate variability.
MATERIALS AND METHODS: The study was conducted at the Department of Physiology at an institute
of national importance, after obtaining necessary ethical approvals from the Institutional Ethics Committee.
Twenty healthy kriya yogi volunteers (mean age: 44 years), who are regular practitioners for the last
10–20 years, were inducted into the study. RNB pranayama starts with closing the right nostril with the
thumb of the left hand followed by exhalation through the right nostril and inhaling slowly through the
same nostril. This forms one round of RNB pranayama. In contrast, inhalation through the left nostril and
exhalation through the right nostril exclusively is called chandrabhedana pranayama (chandrabhedana
means moon‑piercing breath in Sanskrit) with a similar variation called Chandra Anuloma‑Viloma
pranayama in which inhalation, as well as exhalation, is performed through the left nostril exclusively. The
recording of electrocardiogram (ECG) for heart rate variability (HRV) analysis was taken by heart rate
variability (Dinamika HRV‑Advanced Heart Rate Variability Test System, Moscow, Russia). The resting
and during readings of heart rate variability parameters were compared and post hoc analysis was done
using Bonferroni and Holm multiple comparisons for repeated measures.
RESULTS: Time domain parameters: Standard deviation of normal to normal RR intervals (SDNN)
and root mean square of successive NN interval differences (RMSSD) were increased at a high level
of statistical significance during both pranayama maneuvres. Frequency domain parameters: LF, LF/
HF ratio increased significantly. Parasympathetic activity is represented by LF when the respiration
rate is lower than 7 breaths per min or during taking a deep breath. Thus, when the subject is in a
state of relaxation with slow and even breathing in both RNB—right nostril and Chandra—LNB, the
LF values can be very high, indicating an increase in parasympathetic activity rather than an increase
in sympathetic regulation.
CONCLUSION: Our study is an acute study, where changes in HRV were seen after 5 min of RNB
and LNB. However, statistically, there is not much difference in the immediate effects of the two
pranayamas on heart rate variability in regular yoga practitioners.

Keywords

• Heart rate variability
• left nostril breathing
• pranayama
• right nostril breathing