ABSTRACT

INTRODUCTION. The autonomic nervous system (ANS) plays a central role in maintaining physiological homeostasis, with the vagus nerve serving as a primary mediator of parasympathetic activity. Heart rate variability (HRV) is widely recognized as a non-invasive biomarker of autonomic regulation and cardiovascular adaptability. Yoga, particularly its breathing component (pranayama), has been increasingly investigated for its potential to influence autonomic function.

AIM. To examine the neurophysiological mechanisms through which yogic breathing modulates vagal tone and HRV, and to evaluate the current clinical evidence supporting its effects on autonomic regulation.

MATERIALS AND METHODS. A narrative review of the literature was conducted using studies retrieved from biomedical databases, focusing on research investigating yoga, pranayama, HRV, and autonomic nervous system function. Both review articles and clinical studies were included to provide a comprehensive overview of mechanistic and applied evidence.

RESULTS AND DISCUSSION. Evidence suggests that slow, controlled breathing practices characteristic of pranayama are associated with increased parasympathetic activity, enhanced vagal tone, and improved HRV. Mechanistically, these effects are mediated through respiratory sinus arrhythmia and baroreflex sensitivity. Clinical studies generally report reductions in heart rate and stress markers, alongside improvements in autonomic balance. However, findings are not entirely consistent, with some studies reporting no significant changes in HRV, likely due to heterogeneity in study design, population, and intervention protocols.

CONCLUSION. Yogic breathing represents a promising non-pharmacological approach to modulating autonomic function via vagal pathways. While current evidence supports its beneficial role in enhancing HRV and parasympathetic activity, further standardized and large-scale studies are required to establish definitive clinical efficacy.

KEYWORDS: vagal tone, heart rate variability, pranayama, autonomic nervous system, yoga breathing

For citation: Es’haghi M., Safarov M.Sh. Yogic Breathing as a Modulator of Vagal Tone and Heart Rate Variability: A Narrative Review of Neurophysiological Mechanisms and Clinical Evidence. Comorbidity Neurology. 2026; 3 (2): 52–58. https://doi.org/10.62505/3034-185x-2026-3-2-52-58

*For correspondence: Mahdis Es’haghi, Faculty of Medicine, Tver State Medical University, Tver, Russia, e-mail: mahdis.eshaghi@mail.ru.

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ADDITIONAL INFORMATION

Mahdis Es’haghi, Faculty of Medicine, Tver State Medical University, Tver, Russia. E-mail: mahdis.eshaghi@mail.ru. ORCID: https://orcid.org/0009-0003-6853-9344.

Mirali Sh. Safarov, Рhthisiologist, Regional Tuberculosis Hospital, Kaluga, Russia. E-mail: miraliduhtur@mail.ru.

Author contributions. The author confirms their authorship according to the international criteria of the ICMJE.

Funding. This study was not supported by any external sources of funding.

Disclosure. The author declares no apparent or potential conflicts of interest related to the publication of this article.

The content is available under the Creative Commons Attribution 4.0 License.

©2026. Comorbidity Neurology