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Pranayama, the art of breath regulation (or breath control), is a well-established practice in the yogic tradition. More recently, modern research has become interested in the measurable effects of various types of pranayama and the positive impact on physical and mental health.
In this paper, I will explore the positive impact of specific pranayama practices on pulmonary function by highlighting two main pranayama techniques: Bhastrika and Nadi Shodhana. I will discuss their impact on key respiratory parameters like tidal volume (TV), inspiratory and expiratory reserve volumes (IRV & ERV), forced vital capacity (FVC) and vital capacity (VC), therefore demonstrating the following Unit 12 objective: Identify and determine respiratory volumes.
Before discussing the research, it is important to understand the respiratory volumes listed above. Tidal volume (TV) refers to the amount of air inhaled or exhaled during a normal breath (“quiet breathing”). Expiratory reserve volume (ERV) is the amount of air that can be forcefully exhaled past a normal tidal expiration, whereas the inspiratory reserve volume (IRV) is the extra volume that can be brought into the lungs during a forced inspiration. Vital capacity (VC) is the total amount of air that can be exhaled after a full inhalation and is calculated by adding TV, IRV, and ERV. Additionally, forced vital capacity (FVC) is the volume of air exhaled after maximum inhalation. These volumes are indicators of lung function and can be influenced by various factors, including physical activity, health status, and, as this project explores, breath control techniques such as pranayama (Betts, 2022).
First, let’s discuss the research on Bhastrika pranayama. Known as “bellows breath,” this pranayama is an energizing practice characterized by rapid, forceful inhalations and exhalations (imagine a bellows used to stoke a fire). According to Chetry et al., Bhastrika significantly increases VC and ERV as well as positively impacting other measures of pulmonary health including peak expiratory flow rate (PEFR) and forced expiratory volume in the first second (FEV1) (2023). Their systematic review of 17 studies confirmed that both short- and long-term practice leads to improved oxygen uptake, reduced airway resistance, and enhanced respiratory muscle strength (Chetry et al., 2023). This is likely due to the activation and training of both the diaphragm and accessory breathing muscles (Chetry et al., 2023)
A 2019 comparative study looked at the effects of Bhastrika pranayama versus aerobic running in healthy individuals. The study found that Bhastrika produced comparable, and in some cases superior, improvements in key lung function measures such as FVC, FEV1, and PEFR (Budhi et al., 2019). Participants practicing Bhastrika showed greater parasympathetic activation post-intervention than those who ran, indicating a dual benefit of respiratory efficiency and nervous system regulation (Budhi et al., 2019).
The second pranayama we’ll discuss is Nadi Shodhana, or alternate nostril breathing. This breath practice provides a more calming and balancing effect and been used extensively for relaxation as well as therapeutics by many practitioners (Saisupriya et al., 2020). A 2024 case series documented the therapeutic effects of Nadi Shodhana in individuals with impaired pulmonary function. The practice led to measurable increases in FVC and FEV1 over time, suggesting that Nadi Shodhana may support the rehabilitation of lung function in clinical populations (Khatri et al., 2024).. The authors proposed that this effect results from improved vagal tone and greater oxygen delivery through more rhythmic, conscious breathing (Khatri et al., 2024).
In a related 2020 study, Saisupriya et al. examined the clinical applications of Nadi Shodhana when practiced with a 1:3:2 breath ratio (inhaling for 6 seconds, holding for 18 seconds, and exhaling for 12 seconds). In their study, healthy participants practiced the ratio for just five minutes, yet still demonstrated significant changes in both respiratory rate and heart rate variability (Saisupriya et al., 2020). These results point to an immediate modulation of the autonomic nervous system and improved respiratory control (Saisupriya et al., 2020). The lengthened exhalation phase appears to target the ERV and stimulates the parasympathetic nervous system, leading to a calmer physiological state and enhanced breath efficiency for both those with impaired pulmonary function and healthy individuals alike (Saisupriya et al., 2020).
Research consistently shows that pranayama practices not only improve standard pulmonary measures, but also enhances voluntary breath control, oxygen exchange, and nervous system regulation. Unlike traditional clinical respiratory training, which often relies on forced breathing tasks, pranayama offers a sustainable, mind-body approach that integrates physical and mental well-being. Both stimulating and calming techniques have been found to strengthen respiratory muscles, improve neuromuscular coordination, and support overall respiratory function.
For the creative element of my STEAM project, I will teach a brief pranayama practice that includes Bhastrika and Nadi Shodhana, incorporating a 1:3:2 breath ratio during the latter. Participants will be guided to observe how their breath feels before, during, and after the practice, bringing awareness to changes in breath capacity and quality. This experience is designed to integrate scientific learning with somatic exploration, highlighting the connection between respiratory physiology and intentional breath awareness.
You can view my STEAM video submission here: www.fairbanksyoga.com/biol112
References
Betts, J. G., Desaix, P., Johnson, E., Johnson, J. E., Korol, O., Kruse, D., … Young, K. A. (2022). Anatomy and physiology. Houston, TX: OpenStax , Rice University. Retrieved from https://openstax.org/books/anatomy-and-physiology-2e/pages/22-3-the-process-of-breathing
Budhi, R., Payghan, S., & Deepeshwar, S. (2019). Changes in lung function measures following Bhastrika Pranayama (bellows breath) and running in healthy individuals. International Journal of Yoga, 12(3), 233. https://doi.org/10.4103/ijoy.ijoy_43_18
Chetry, D., Chhetri, A., & Yadav, K. (2023). Effects of bhastrika pranayama (yoga bellows-type breathing) on pulmonary, cardiovascular, and psychological variables: A systematic review. Yoga Mimamsa, 55(1), 67–76. https://doi.org/10.4103/ym.ym_9_23
Khatri, M., & C Mangal, P. (2024). The therapeutic effects of Nadi Shodhana Pranayama on pulmonary functions: A case series. International Journal of Science and Research (IJSR), 13(9), 758–761. https://doi.org/10.21275/sr24912221701
Saisupriya, K., Chandrappa, S. H., Shetty, S. K., Shetty, P., Honnegowda, T. M., & Hiremath, L. (2020). Analysis of immediate effect of Nadishodhana Pranayama in the ratio of 1:3:2 on autonomic and respiratory variables in healthy individuals. Yoga Mimamsa, 52(1), 20–24. https://doi.org/10.4103/ym.ym_21_19