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Differential effects of unilateral forced nostril breathing on baroreflex sensitivity and cardiovascular parameters
Madhavan Chandran1, Vivek K Sharma2, R Aruna1
1Department of Physiology, All India Institute of Medical Sciences, Kalyani, West Bengal, India.
Background:
Baroreflex sensitivity (BRS) is a crucial marker of autonomic cardiovascular control, and it is also a predictor of cardiovascular risk. Unilateral forced nostril breathing (UFNB) is one of the many types of pranayama, which are breathing techniques in Yoga. This type of breathing can influence autonomic function through hemispheric activation, yet its direct impact on BRS remains unexplored. To assess the immediate effects of left and right UFNB on BRS and cardiovascular parameters in healthy young adult men.
Materials And Methods:
It is a cross-section study, which included 55 healthy adult men (mean age 25.67 ± 5.89 years). The participants underwent the standardized protocols for measuring BRS, blood pressure, and heart rate during baseline and the 2-minute interventions of left and right UFNB. BRS was measured using the sequence method with Finapres technology. Paired t-tests were used to compare the baseline and the postintervention values.
Results:
Performing left UFNB significantly increased BRS by 19.6% (P < 0.001, d = 3.63), whereas the blood pressure and heart rate decreased (all P < 0.001), probably indicating profound activation of parasympathetic system. On the other hand, performing the right UFNB decreased BRS by 5.6% (P = 0.012, d = 0.35) and also increased blood pressure and heart rate (all P < 0.01), probably suggesting a sympathetic activation. Waist circumference correlated negatively with the baseline BRS values (r = -0.513, P < 0.001).
Conclusion:
Left UFNB produces substantial immediate improvements in BRS with parasympathetic enhancement, whereas right UFNB induces sympathetic activation. These findings suggest a potential therapeutic application for the use of UFNB in cardiovascular health management as a nonpharmacological intervention.
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