Breathwork: A Comprehensive Exploration

What is Breathwork? Breathwork refers to conscious breathing practices and techniques influencing physical, mental, and emotional states. These structured breathing exercises help regulate the nervous system, release stored tension, process emotions, and enhance overall well-being by changing breathing patterns to create specific physiological and psychological effects.

Harnessing the power of your breath represents one of the most accessible yet profound tools for transformation available. This ancient practice, now supported by modern science, offers a direct pathway to physiological and psychological change that addresses root causes rather than merely managing symptoms. The following exploration reveals how specific breathing patterns can permanently shift your nervous system, release deep-seated trauma, and create lasting well-being far beyond the practice.

Introduction to Breathwork: What is Breathwork?

Breathwork encompasses practices focused on intentional breathing patterns designed to create specific physiological and psychological effects. Unlike automatic breathing, breathwork introduces deliberate changes to breath rate, depth, and rhythm that can rapidly transform your internal state.

The history of breathwork spans thousands of years across diverse cultures. Ancient yogic traditions developed pranayama (breath control), Chinese medical traditions incorporated breath practices within qigong, and indigenous ceremonies worldwide featured rhythmic breathing. These ancestral practices recognized breath as a powerful tool for altering consciousness and promoting healing.

Modern breathwork emerged in the late 20th century when pioneers began systematizing these approaches. Leonard Orr developed Rebirthing Breathwork after experiencing profound healing through continuous breathing techniques. At the same time, psychiatrist Stanislav Grof created Holotropic Breathwork as a non-drug alternative for accessing non-ordinary states of consciousness.

Breathwork differs from ordinary breathing in that it involves conscious engagement with a process that typically operates automatically. This shift directly impacts physiological systems, usually beyond voluntary control, creating opportunities to address root causes rather than manage symptoms.

Physiological Aspects of Breathwork: Holistic Breathing Techniques

Understanding how breathwork affects the body reveals why it's so effective for creating lasting change. Conscious breathing's physiological impact extends beyond simple relaxation, influencing everything from nervous system regulation to biochemical processes affecting the entire being. Let's examine the key physical mechanisms that make breathwork such a powerful tool for transformation.

The Mechanics of Breathing: Breath Control Therapy

Effective breathing engages the diaphragm, a dome-shaped muscle separating the chest and abdominal cavities. When you inhale, the diaphragm contracts and flattens, creating negative pressure that draws air into your lungs. During exhalation, this muscle relaxes, and the elastic recoil of lung tissue pushes air outward.

Most adults utilize only 20-30% of their respiratory capacity, breathing primarily into the upper chest. This restricted breathing pattern keeps the body in a mild state of stress activation. Diaphragmatic breathing—foundational to effective breathwork—engages the lower lobes of the lungs, where the majority of oxygen exchange occurs.

The complete breathing cycle contains four phases: inhalation, retention after inhalation, exhalation, and retention after exhalation. Different breathwork methods emphasize or modify these phases for specific effects. Extending the exhale activates the parasympathetic response while emphasizing inhalation and retention, which produces stimulating effects.

Breathwork's Impact on the Nervous System

Your autonomic nervous system operates primarily through two branches: the sympathetic (activating "fight-or-flight") and the parasympathetic (promoting "rest-and-digest"). Your breathing pattern directly influences which branch dominates. Rapid, shallow breathing activates the sympathetic response, while slow, deep breathing stimulates parasympathetic activity.

This connection creates a bidirectional relationship between emotional state and breathing—anxiety produces rapid breathing, but rapid breathing also generates anxiety. Intentional breathing breaks this cycle by intentionally altering respiratory patterns, effectively "resetting" the autonomic nervous system and creating new pathways for regulation.

Neuroscientist Dr. Stephen Porges' Polyvagal Theory explains how specific breathing patterns stimulate the vagus nerve—the primary parasympathetic pathway.¹ Regular vagal nerve stimulation through breathwork strengthens vagal tone, improving emotional regulation and stress resilience. This represents a fundamental shift in nervous system function rather than temporary symptom suppression.

Cardiovascular Benefits of Breathwork

The respiratory and cardiovascular systems share intimate connections, with breathing patterns significantly influencing heart function. Research demonstrates that specific breathwork practices reduce blood pressure, with effects comparable to some pharmacological interventions when practiced consistently.

Heart rate variability (HRV)—the natural variation in time intervals between heartbeats—is a critical indicator of autonomic function and overall health. Low HRV correlates with increased disease risk and reduced emotional flexibility, while high HRV indicates robust regulatory capacity. The healing benefits of deep breathing include significantly improved HRV measures even with brief daily practice, suggesting profound changes in autonomic regulation that extend far beyond the practice.²

These cardiovascular changes stem from multiple mechanisms. Slow breathing at approximately 5-6 breaths per minute optimizes the natural synchronization between breath and heart rhythm. Additionally, deep breathing improves circulation, benefiting every system in the body and creating a foundation for comprehensive health.

Psychological and Mental Health Benefits

Breathwork has profound mental health benefits, as it can simultaneously create change at neurological and psychological levels. Unlike approaches that work solely through cognitive pathways, breathwork directly influences the physiological underpinnings of emotional states, creating conditions where new patterns can naturally emerge. The following sections explore specific ways breathwork transforms psychological well-being.

Reducing Anxiety and Depression: How to Use Breathwork for Mental Clarity

Breathwork offers powerful benefits for anxiety and mood disorders. It works through physiological pathways that complement cognitive approaches. Unlike strategies that address only thought patterns, breathwork creates tangible changes in the biological underpinnings of emotional distress.

Breath-focused practices consistently demonstrate efficacy for anxiety conditions. Multiple studies have found significant reductions in self-reported and physiological measures of anxiety through regular breathwork.³ The mechanisms include increased parasympathetic activity, improved emotional regulation, and enhanced prefrontal cortex function, which creates a foundation for lasting nervous system change rather than temporary symptom management.

Depression also responds well to breathwork interventions. Research comparing rhythmic breathing practices with both cognitive therapy and medication for depression has shown comparable results, with participants maintaining improvements at follow-up assessments. Notably, breathwork groups showed significant neurochemical changes that support mood regulation.

Breathwork distinguishes itself from conventional approaches because it simultaneously addresses emotional distress's somatic and cognitive aspects. By creating physiological conditions incompatible with anxiety and depression, breathwork helps break self-reinforcing cycles, opening space for new emotional experiences.

Enhancing Mental Clarity and Focus: Understanding Breathwork Techniques

Beyond alleviating distress, breathwork actively promotes optimal cognitive function. Research demonstrates substantial attention, executive function, and information processing improvements following specific breathing interventions.⁴

Controlled breathing enhances cognitive function through several mechanisms. It increases cerebral blood flow and oxygenation, providing neurons with essential nutrients. It reduces stress-related cognitive interference, allowing better allocation of mental resources. It also activates brain regions associated with attention control.

Perhaps most importantly, breathwork develops metacognitive awareness—the ability to observe one's thinking processes. This heightened awareness allows one to recognize when attention has wandered and consciously redirect it, building the fundamental skill underlying all forms of cognitive control. Unlike temporary cognitive enhancers, breathwork strengthens these core capacities over time.

Breathwork Techniques and Practices

The variety of breathwork approaches available today reflects different pathways to transformation, each with unique benefits and applications. Some techniques produce immediate calming effects, while others facilitate deeper emotional processing or expanded awareness. Understanding these different methods allows you to select approaches that align with your needs and goals. Each technique creates distinct physiological and psychological effects through simple yet powerful breathing patterns.

Popular Breathwork Techniques: What Are the Different Types of Breathwork?

The following techniques represent some of today's most effective and widely practiced breathwork methods. Each approach creates distinct effects through specific breathing patterns and contexts, allowing you to select strategies that align with your needs. While some techniques produce immediate calming effects, others facilitate deeper emotional processing or expanded awareness states.

Box Breathing

Box breathing employs a 4:4:4:4 pattern—inhaling for four counts, holding for 4, exhaling for 4, and holding for four before beginning again. This technique creates balanced autonomic activation, making it excellent for transitioning between states or stabilizing the nervous system during stress. Navy SEALs use this technique for combat readiness, demonstrating its effectiveness under extreme pressure.

Conscious Connected Breathwork

Circular breathing techniques involves continuous breathing without pauses between inhalation and exhalation. This technique creates a circular breath flow that helps bypass standard thought patterns and access deeper emotional material. Practitioners maintain an open mouth while inhaling and exhaling, breathing deeply into the lower abdomen slightly faster than normal breathing.

This method forms the foundation of several modern breathwork systems, including Rebirthing and Transformational Breath. The continuous breathing pattern can activate the sympathetic nervous system, sometimes leading to tingling sensations, emotional releases, or spontaneous body movements as energy moves through previously restricted pathways.

Sessions typically last 30-60 minutes in a supported environment. This technique is particularly effective for emotional processing, releasing energetic blockages, and accessing insight that may be inaccessible through cognitive approaches alone. Due to its potentially intense effects, beginning practitioners often benefit from working with an experienced breathwork practitioner who can create a safe container and expertly guide them through the transformative process.

Alternate Nostril Breathing

Alternate nostril breathing (Nadi Shodhana) involves using your fingers to breathe through the left and right nostrils in specific patterns. Begin by closing your right nostril with your right thumb and inhaling through your left nostril. Close both nostrils briefly, then release your right nostril while keeping the left closed and exhale. Reverse the pattern, continuing for several minutes. This technique balances sympathetic and parasympathetic activity while harmonizing the brain hemispheres.

4-7-8 Breathing

The 4-7-8 technique involves inhaling quietly through the nose for four counts, holding the breath for seven counts, and exhaling entirely through the mouth for eight counts. This pattern powerfully activates the parasympathetic nervous system due to the extended exhale phase. Developed by integrative medicine pioneer Dr. Andrew Weil, it's particularly effective for managing acute anxiety, preparing for sleep, or interrupting reactive patterns.

Coherent Breathing

Coherent breathing involves synchronizing breath and heart rhythms by maintaining a steady rate of about 5-6 breaths per minute—typically inhaling and exhaling for equal counts of 5 or 6. This pace optimizes heart rate variability and creates a psychophysiological coherence where multiple body systems operate harmoniously. Its simplicity makes it ideal for daily practice, gradually resetting autonomic balance over time.

Somatic Breathwork

Body-based breathwork integrates conscious breathing with awareness of bodily sensations, movement, and emotional release. Unlike techniques focusing primarily on breathing mechanics, somatic approaches emphasize the relationship between breath and physical experience. They use breath as a tool to access and release tension held in the body.

In practice, somatic breathwork often begins with a body scan to identify areas of constriction. Practitioners then direct breath awareness into these areas, allowing spontaneous movements or emotional expressions to emerge. This process helps release chronic tension patterns and access embodied memories that may be inaccessible through cognitive approaches alone.

The effectiveness of somatic breathwork stems from its recognition that psychological material is stored physically in the body—particularly in areas of chronic muscular tension. Combining breath, awareness, and permission for authentic expression creates conditions where the body can release held patterns, addressing trauma at its somatic source.

Holotropic Breathwork

Holotropic Breathwork involves continuous circular breathing—deep, rapid breaths without pauses between inhale and exhale—accompanied by evocative music in a supported setting. This intensive technique can induce non-ordinary states of consciousness that facilitate psychological processing and spiritual exploration. Some practitioners report experiences similar to those associated with breath-induced altered states, where intense breathing can trigger natural biochemical processes that create profound altered states without external substances.

Sessions typically last 2-3 hours and are led by certified facilitators. The technique occasionally produces experiences resembling birth trauma, emotional catharsis, or mystical states, with participants reporting meaningful insights and resolution of long-standing issues. Due to its intensity, Holotropic Breathwork requires screening for contraindications and professional facilitation.

Structuring a Breathwork Session

A breathwork session begins with creating an environment conducive to practice, minimizing distractions, and ensuring comfortable positioning. Start with a clear intention that aligns with your current needs, such as reducing anxiety, processing emotions, or cultivating presence.

You can start the session with a centering practice to establish present-moment awareness. For example, you could scan your body for sensations or observe your natural breathing pattern. This baseline awareness will help you recognize the changes during active practice.

The core breathwork component will vary based on your intention and experience level. Begin with manageable durations—even 5-10 minutes produces tangible benefits. As you develop capacity, sessions can extend to 20-30 minutes or longer for more intensive techniques.

Include an integration period after the active breathing phase to notice the effects without immediately returning to regular activity. This transition space helps consolidate the physiological and psychological shifts, making them more likely to persist beyond the session.

Regarding timing, morning practices often promote clarity for the day ahead, while evening sessions help release accumulated tension and prepare for sleep. You can experiment to discover what works best for your unique system.

Integration with Other Practices

Breathwork is a standalone practice and a powerful complement to other modalities, creating synergistic effects that enhance overall outcomes. The conscious breath is a bridge between different approaches, amplifying their benefits while providing a consistent foundation for transformation. These integrative combinations often create results more significant than the sum of their parts, simultaneously addressing multiple dimensions of well-being.

Yoga and Breathwork: Somatic Breath Practices

Yoga and breathwork share a synergistic relationship dating back thousands of years. In traditional yoga, physical postures were mainly developed to prepare the body for breathwork and meditation, creating an integrated system for transformation.

Yoga postures help release tension in the diaphragm, intercostal muscles, and surrounding fascia, creating optimal conditions for adequate breathing. Specific poses target different aspects of respiratory function—backbends expand chest capacity, forward folds encourage abdominal breathing, and twists improve intercostal flexibility.

Conversely, breathwork amplifies yoga's benefits by directing energy through newly opened channels in the body. This combination creates a positive feedback loop: postures improve breathing capacity, while conscious breathing enhances the energetic effects of the postures.

Match breathing techniques with appropriate activities for optimal integration. Energizing breathwork complements active practices while calming techniques enhance restorative work. Regardless of the specific approach, bringing conscious awareness to breathing during movement transforms mechanical exercise into mindful practice.

Meditation and Breathwork: The Power of Breathwork

Meditation and breathwork represent complementary aspects of contemplative practice. Traditional meditation systems often use natural breath awareness as an anchor for attention, while breathwork modifies breathing patterns to create specific states that facilitate meditation.

This complementary relationship works through several mechanisms. Breathwork creates physiological conditions conducive to meditation by calming the nervous system and reducing mental chatter. This preparation helps overcome everyday obstacles, such as restlessness, that often challenge beginning meditators.

Conversely, meditation develops sustained attention and present-moment awareness that enhances breathwork effectiveness. The capacity to notice subtle respiratory sensations and maintain focus during breathwork comes directly from meditation skills.

The two approaches can be combined effectively in various sequences. Beginning with active breathwork before transitioning to meditation creates an ideal progression from doing to being. Alternatively, brief meditation periods between rounds of intensive breathwork provide integration spaces that enhance overall effectiveness.

Long-Term Benefits and Considerations: How Does Breathwork Work?

The true power of breathwork emerges through consistent practice over time, as temporary shifts gradually become lasting changes in your baseline functioning. Unlike approaches that create dependency on external intervention, breathwork progressively builds internal resources and self-regulatory capacity. This section explores how regular practice creates cumulative benefits beyond individual sessions, transforming your relationship with challenging experiences and building resilience from within.

Consistent breathwork practice creates cumulative benefits that extend far beyond individual sessions. Research indicates regular practitioners experience lasting improvements in baseline physiological function, emotional regulation, and cognitive performance.⁵, Unlike approaches that require ongoing external intervention, breathwork creates progressive autonomic shifts that become your new baseline.

Psychologically, long-term practitioners report enhanced emotional resilience—the capacity to respond flexibly to challenges rather than react automatically. This resilience stems from improved interoception (awareness of internal bodily sensations) and the development of regulatory skills that become increasingly accessible with practice.

Most significantly, regular breathwork gradually changes one's relationship with difficult experiences. Rather than avoiding discomfort, practitioners develop the capacity to stay present with challenging sensations and emotions while maintaining physiological regulation. This fundamental shift—from reactivity to responsive presence—transforms how one navigates all aspects of life.

For optimal long-term results, consistency matters more than intensity. Daily practice creates more substantial benefits than occasional longer sessions, as it repeatedly reinforces neural pathways related to self-regulation.

Trauma & Emotional Release From Breathwork: Best Breathwork Techniques for Stress Relief

Traumatic experiences create distinctive body and nervous system patterns that often resist conventional treatment approaches. Breathwork provides a direct pathway to these stored patterns, offering possibilities for release and integration not available through purely cognitive methods. Its effectiveness stems from breathwork's ability to create physiological conditions where trauma processing can occur naturally without forcing or retraumatizing the system.

How Does Breathwork Help You Overcome Past Trauma?

Trauma creates distinctive patterns in both the body and nervous system that persist long after the traumatic event has passed. While cognitive approaches address the narrative aspects of trauma, they often cannot reach the somatic imprints where trauma memory resides. Breathwork for trauma recovery provides direct access to these physiological patterns that talk therapy alone cannot address.

Trauma fundamentally disrupts the nervous system's natural regulation, often leaving individuals stuck in states of hyperarousal or hyperarousal. Breathwork directly influences these autonomic states, creating a physiological environment where processing can occur within a window of tolerance—neither overwhelmed nor dissociated.

When traumatic experiences occur, the body's natural defensive responses are often interrupted, leaving activation energy trapped in the system. Specific trauma-informed breathwork techniques help complete these interrupted response cycles, allowing the discharge of bound energy and return to regulation.

The body stores trauma in patterns of muscular tension, restricted breathing, and altered posture. Breathwork combined with somatic awareness helps identify and release these patterns, restoring natural movement and vitality to areas previously constricted by trauma responses.

Most importantly, breathwork restores a sense of agency often compromised by traumatic experiences. The simple act of consciously changing one's breathing pattern demonstrates to the nervous system that one now has choice and control—fundamental aspects of safety that trauma undermines.

How Does Breathwork Release Trauma? How Breathwork Impacts the Nervous System

The process of releasing trauma through breathwork involves several distinct physiological and psychological mechanisms. Slow, deep breathing with extended exhalation activates the parasympathetic nervous system, creating safety conditions necessary for trauma processing.

Focused breathwork increases interoceptive awareness and the ability to sense internal bodily signals. Trauma often involves disconnection from bodily sensation as a protective mechanism. Breathwork gradually restores this connection, allowing access to somatic information containing the trauma's imprint and the key to its resolution.

Certain breathwork techniques temporarily alter consciousness by changing blood chemistry and brainwave patterns. These altered states bypass chronic defense mechanisms, allowing access to material typically held outside awareness.

The emotional release that sometimes accompanies breathwork represents the discharge of survival energy that remains bound in the nervous system after traumatic experiences. This isn't simply emotional catharsis but the completion of interrupted biological processes essential for returning to regulation.

Importantly, effective trauma release through breathwork doesn't require re-experiencing traumatic events in detail. Rather than focusing on narrative content, breathwork emphasizes the physiological completion of interrupted responses. This somatic approach often avoids retraumatization while still facilitating deep resolution.

Is Breathwork Safe? Science-Backed Benefits of Breathwork

While breathwork offers profound benefits, approaching these practices with appropriate knowledge and preparation maximizes safety and effectiveness. Most basic techniques present minimal risk when practiced correctly, but understanding potential contraindications and proper progression helps ensure positive experiences. This section addresses essential safety considerations and guides approaching breathwork responsibly, whether practicing independently or with facilitation.

When approached appropriately, most basic breathwork techniques present minimal risk. However, certain practices—particularly those involving hyperventilation or extended breath retention—require proper understanding and supervision.

Medical conditions that may require modification or contraindicate certain breathwork practices include uncontrolled hypertension, cardiovascular conditions, epilepsy, glaucoma, significant psychiatric conditions, recent surgery, and pregnancy. If you have these or other significant health concerns, consult healthcare providers before beginning intensive breathwork.

Even for those without medical contraindications, it's essential to approach breathwork progressively. Begin with gentle techniques and gradually build capacity as your system adapts. Common transient responses to breathwork include lightheadedness, tingling in the extremities, muscle tension, and emotional releases. While generally normal and self-limiting, severe discomfort indicates a need to modify your approach.

The psychological material that emerges during breathwork can sometimes surprise practitioners with its intensity. Appropriate support—whether a qualified facilitator, therapist, or knowledgeable community—helps constructively integrate these experiences.

Breathwork Certification

As breathwork continues to gain recognition within the healthcare and wellness fields, questions about qualifications and standards become increasingly relevant. Understanding what constitutes quality training helps prospective practitioners choose a certification path and individuals seeking qualified facilitators. The field currently encompasses diverse lineages and approaches, each with its training standards and emphases in the absence of universal regulation.

As breathwork gains recognition within healthcare and wellness, questions about qualifications and standards become increasingly important. Professional breathwork coaching requires proper training, as no regulatory body oversees all breathwork approaches. This results in varied training requirements across different lineages and schools.

Reputable accredited breathwork certification programs typically include several essential components: comprehensive instruction in respiratory physiology, extensive personal practice, supervised teaching opportunities, and ethics training. Training depth varies significantly across programs, from weekend certifications covering basic techniques to multi-year commitments involving hundreds of training hours.

When looking for a breathwork practitioner or considering pursuing a certified breathwork facilitator program, you can review the program's comprehensiveness, faculty qualifications, ethical guidelines, and recognition within professional communities. The International Breathwork Foundation (IBF) and Global Professional Breathwork Alliance (GPBA) provide standards and directories, though many qualified practitioners also train through independent lineages with deep expertise in specific modalities.

Beyond formal credentials, an effective breathwork practice requires qualities no certificate guarantees: presence, intuition, ethical boundaries, and extensive personal practice. The most skilled practitioners combine technical knowledge with these less tangible qualities, which they have developed through their transformation work.

Conclusion

Breathwork stands apart in its elegant simplicity and profound potential—accessible enough that anyone can begin immediately, yet sophisticated enough to facilitate lasting transformation. The breath offers a direct pathway to systems typically beyond conscious control, opening possibilities for change that many approaches cannot access.

Research supporting breathwork continues expanding, with studies documenting benefits from improved cardiovascular health to enhanced emotional regulation and cognitive performance. This growing evidence base validates traditional wisdom while illuminating the physiological mechanisms underlying breathwork's effectiveness.

Breathwork distinguishes itself from many therapeutic approaches by emphasizing self-regulation rather than external intervention. The breath remains continuously available as a tool for transformation, requiring no special equipment or circumstances—only your awareness and intention. This accessibility creates genuine autonomy, empowering you to address challenges directly.

As with any practice, consistent engagement rather than sporadic intensity is the most significant benefit. Even five minutes of conscious breathing daily creates cumulative effects that gradually shift baseline functioning. You can begin with what you think is manageable in your current circumstances, trusting that your capacity will naturally expand with regular practice.

Whether addressing specific conditions, enhancing performance, or deepening self-understanding, breathwork offers pathways to the changes you seek—not through force or control but by creating conditions where natural healing and integration emerge.

Frequently Asked Questions

How long does it take to see results from breathwork? Many people experience immediate benefits like reduced anxiety and increased calm after just one session. However, lasting transformation typically develops over 4-6 weeks of consistent practice. Even 5-10 minutes daily creates cumulative effects that gradually reset your nervous system's baseline functioning.

Can breathwork help with chronic pain? Breathwork can significantly reduce chronic pain by addressing physiological and psychological components. It decreases muscle tension, increases oxygen flow to tissues, reduces inflammation, and modifies pain perception by activating parasympathetic responses. Regular practice helps break the pain-stress cycle at its source.

Is breathwork dangerous during pregnancy? Gentle breathwork techniques like diaphragmatic breathing are safe and beneficial during pregnancy. However, intensive practices involving hyperventilation, breath retention, or pressure on the abdomen should be avoided. Always consult with your healthcare provider and work with instructors experienced in prenatal modifications.

How does breathwork differ from meditation? While meditation often involves passive breath observation, breathwork actively manipulates breathing patterns to create specific physiological effects. Meditation cultivates non-reactive awareness, while breathwork directly shifts your nervous system state. They work synergistically—breathwork creates conditions conducive to meditation, while meditation enhances awareness of subtle breathing sensations.

Do I need a facilitator for breathwork, or can I practice alone? Basic techniques like box breathing and 4-7-8 breathing can be safely practiced independently. However, more profound practices like conscious connected breathwork benefit from professional guidance, especially initially. A skilled facilitator provides safety, proper technique instruction, and integration support for emotional material that may arise.

References

¹ Porges SW. The polyvagal perspective. Biol Psychol. 2007;74(2):116-143. doi:10.1016/j.biopsycho.2006.06.009

² McCraty R, Zayas MA. Cardiac coherence, self-regulation, autonomic stability, and psychosocial well-being. Front Psychol. 2014;5:1090. doi:10.3389/fpsyg.2014.01090

³ Zaccaro A, Piarulli A, Laurino M, et al. How Breath-Control Can Change Your Life: A Systematic Review on Psycho-Physiological Correlates of Slow Breathing. Front Hum Neurosci. 2018;12:353. doi:10.3389/fnhum.2018.00353

⁴ Novaes MM, Palhano-Fontes F, Onias H, et al. Effects of Yoga Respiratory Practice (Bhastrika pranayama) on Anxiety, Affect, and Brain Functional Connectivity and Activity: A Randomized Controlled Trial. Front Psychiatry. 2020;11:467. doi:10.3389/fpsyt.2020.00467

⁵ Pal GK, Velkumary S, Madanmohan. Effect of short-term practice of breathing exercises on autonomic functions in normal human volunteers. Indian J Med Res. 2004;120(2):115-121