What Is Breathwork? – Explanation Of Different Breathwork Techniques Vs. Pranayama

As there are so many different breathwork styles, I decided it was time for me to write an article that explains the most popular styles, that led me to create my own, and fast growing in popularity, breathwork practice called SOMA Breath.

This article will explain to you the difference various popular breathwork practices and their ancient counterpart, Pranayama.

You will learn:

  • The difference between some of the most popular breathwork today.
  • How breathwork directly influences your physiology.
  • What Pranayama is.
  • Some surprising information about our bodies’ oxygen and carbon dioxide needs.
  • How SOMA Breath sets itself apart from both breathwork and Pranayama, offering you something totally unique.

If you want to try the SOMA Breathwork technique I offer free sessions every Sunday where you can learn all about the technique and even experience a session online. Click here to join our next session.

The Most Popular Styles Of Breathwork That Exist Today

There are numerous styles of breathwork however here are the most popular breathwork styles with a description of how they work and what they are used for:

SOMA Breath

So while SOMA Breath techniques do fit into the category of breathwork, SOMA Breath also fits into the category of Pranayama. But it still doesn’t totally fit into either category. SOMA Breath is a complete holistic system of breathwork techniques. There is no one size fits all, and SOMA takes into account the fact that every single person is unique and may require different breathing techniques depending on their needs (especially if health related or medical).

SOMA Therapeutic Breathwork techniques are the core pranayama techniques that have the most scientific evidence to support their function.

The SOMA Awakening is inspired by the most revered Pranayama technique called Nishessha Rechaka Kumbhaka and the ancient ritual of Soma that appears more than 50,000 times in the ancient text, the Rig Veda. The Rig Veda is the basis of modern day Hinduism and the Vedic philosophy that Yoga originates from. 

The SOMA Awakening is also inspired by the core breathwork technique of the Wim Hof Method, the work of Dr Prakash Malshe an Indian doctor based near Rishikesh – the birthplace of Yoga – who uses Pranayama and Yoga to treat his patients, and by Swami Ambikananda Saraswati of the Traditional Yoga Association in the UK who has one of the most popular Yoga schools that teaches methods based on the earliest recorded traditional Yoga practices.

SOMA Breath techniques are designed to be practiced regularly, some on a daily basis, and lead to improvements in every area of your life.

How Does SOMA Breath Work?

SOMA Breath takes the fundamental Pranayama techniques listed above, puts them in the correct combination to use for the intended therapeutic function and makes them easy and accessible to anyone who would like to benefit from them.

These breathwork exercises become your toolbox of techniques that you can use to treat or prevent a range of issues that may arise in your body.

Think of SOMA Breath as a means to activate your “Inner Pharmacy” through the power of your breath.

Soma Therapeutic Breathwork

1. RELAX/REST: How to turn off stress and lower heart rate & blood pressure
2. ENERGY: How to raise core body temperature, heart rate and produce a controlled stress response to ward of illness and inflammatory diseases.
3. LONGEVITY: Benefits of intermittent hypoxia for more stamina, better circulation and even ability to move stem cells around the body for anti-aging, longevity and peak performance.
4. DETOX: How to clear toxins from your gut, remove nasal and sinus congestion and purify your blood.
5. CLEANSE: How to drink air to purify digestive system, suppress hunger, eliminate bad bacteria and promote growth of good bacteria.

The SOMA Awakening

The Awakening is a full 1.5hr breathwork ceremony featuring a series of ancient breathing techniques put into a sequence that combines rhythmical breathing to beat-driven music and includes vocal toning/humming, breath retention, meditation, visualisation techniques, and the activation and transmutation of sexual energy.

This can:

  • Awaken dormant functions of the brain.
  • Enhance creativity and problem solving.
  • Create heightened states of consciousness and inspiration.
  • Improve brain function and mind power.
  • Cleanse and purify the bloodstream and lymphatic system.
  • Stimulate self healing.
  • Reduce depression/anxiety.
  • Clear negative imprints and traumas from early life (0-7 years).
  • Reimprint your mind with more empowering beliefs and habits.
  • Set intentions and create the motivation and energy to complete important goals.
  • Self realisation: discover your true self and your deepest inner calling.

The Awakening is one of the most popular experiences that I facilitate at my various events and festivals around the world. It literally wakes people up to their full human potential!

Scientific Explanation Of SOMA Breath

When you breathe in, you inhale oxygen (and other molecules and gases), when you breathe out, you exhale co2 (and other molecules and gases). That’s respiration.

When you breathe in, your HR goes up a bit. When you breathe out, your heart rate goes down a bit (Lehrer, 2007). This is the basic principle of respiration, but it is also important for metabolism.

When you breathe in O₂, it binds to red blood cells from your lungs. Those blood cells transport oxygen to tissue and organ cells thanks to the pumping action of your heart. The oxygen is needed by the mitochondria in the cells of your body as a means of energy, like a fire (“Cellular Respiration”, n. d.)

Imagine you have a fire burning inside of you that produces all the energy you need to live.

Too little oxygen, and a fire cannot burn at all. Just like in our bodies: too little oxygen and we can’t survive. If a fire has too much oxygen, it will burn too much and potentially cause some damage. If our body has too much oxygen, it causes something called oxidative stress. Oxidative stress happens when there is an imbalance between free radicals and antioxidants in our body. It can lead to cell and tissue damage.

So it is clear that we need the right balance of oxygen; not too much and not too little.

O₂ + Glucose ⇨ ATP (energy) + CO₂+ H₂O

The oxygen you inhale is carried around your body by red blood cells and it combines with glucose in the mitochondria of your cells, which produces adenosine triphosphate (ATP) energy, carbon dioxide (CO₂), and water (H₂O). When you exhale, you breathe out the carbon dioxide and water. The ATP provides energy to your body, so it can function normally.

Inhalation stimulates your sympathetic nervous system, exhalation stimulates the parasympathetic nervous system. By changing the way you breathe you can make one of them more dominant than the other depending on what you want (Russo et al., 2017).

Rapid breathing and taking in more oxygen than normal breathing will energise your body. It will also cause contraction in the body as you breathe out carbon dioxide at a faster rate, stimulating the sympathetic nervous system.

Slowing down your breathing and extending your exhale to be longer than your inhale will have a relaxing effect on the body. It causes an increase in carbon dioxide levels and also stimulates the production of nitric oxide, which dilates blood vessels (vasodilation). Vasodilation reduces blood pressure and increases blood flow (Russo et al., 2017).

How Your Body Rusts

We’re not trained or taught how to breathe when we’re young. Over the years we experience stress, challenges, and activation of the sympathetic nervous system, and so on, so we don’t consciously breathe. Instead, we tend to breathe under control of the reptilian brain, which means our breathing can become erratic, fast, slow, or it can just pause without conscious control. That leads to incoherent heart rhythms, which leads to incoherent functions in the body.

When you expose metal to air for long periods of time, the oxygen in the atmosphere reacts with the metal through a process called oxidation that causes it to rust. The same rusting occurs in the body that can lead to inflammation and cell damage. This is why it is beneficial to consciously control the amount of oxygen that goes into the body.

Too much oxygen as a result of over-breathing leads to oxidative stress. Oxidative stress is like a rusting of your arteries and veins because the oxygen is unable to release itself from your red blood cells. It leads to inflammation, plaque, and corroding. If you exercise too much or do too much physically strenuous work, that can also cause oxidative stress. In fact, just being stressed out in general can cause oxidative stress because our breathing is erratic and inefficient.

Too much oxygen and inefficient oxygen use leads to oxidative stress, which leads to free radicals attacking your system. This leads to protein and DNA injury, tissue damage, inflammation, and cell death. Autoimmune conditions, neurodegenerative diseases, and cancer can occur as a result of oxidative stress (Uttara et al., 2009; Reuter et al., 2010; Bashir et al., 1993; Asmat et al., 2016).

Similarly, if you do not use oxygen efficiently, you can experience low moods, depression, low energy, and no motivation (Black et al., 2015).

By a process known as the Bohr effect, an increase in carbon dioxide results in a decrease of blood pH (more acidic), which makes the haemoglobin proteins release their oxygen. When the haemoglobin releases oxygen, it goes to the tissue cells of your body, to the mitochondria, to create ATP energy. You need a certain concentration of carbon dioxide in your body for this to happen.

When you are stressed or anxious, you over-breathe (hyperventilate). This causes you to have too little carbon dioxide in your body, so the haemoglobin is not prompted to release oxygen sufficiently. That means there is not enough oxygen going to our cells where it is needed to create ATP energy – which keeps us alive and functioning!

So disease can also be the result of over breathing or hyperventilation that happens when you are stressed or anxious which causes you to have too little carbon dioxide and too much oxygen bound to haemoglobin and not enough going into the cells where it is needed to create energy.

One of the aims of SOMA Breath is to help you create the optimum balance of oxygen and carbon dioxide for your body, so that you can experience a consistent flow of energy, increased productivity, better and more regulated moods, and be more resistant to stress. It can also help you stay physically healthy, and reduce your chances of getting diseases associated with excessive or a lack of oxygen.

Yoga may have been developed to help you become super efficient at burning oxygen, giving you the right amount of carbon dioxide in your body, so that you can survive with less oxygen, creating less oxidative stress on the body, promoting longer, disease free lives.

pH – The Most Important Factor For Life To Exist

For the important chemical processes in your body to function correctly, your blood needs to be at a pH of 7.4 – slightly alkaline. Therefore, your body automatically does its best to maintain this exact pH value. Oxygen increases the alkalinity of your blood (higher pH), while carbon dioxide makes it more acidic (lower pH) (“Acidosis and Alkalosis”, 2018).

A pulse oximeter measures something called SpO₂ (peripheral capillary oxygen saturation), which is an estimated measure of the amount of oxygen in the blood (Chan et al., 2013). It may surprise you to learn that we have a total abundance of oxygen in our bloodstream: most people have a 97-99% SpO₂ reading under normal conditions and it is not easy to significantly reduce this measurement (“What Does SpO₂ Mean?”, n. d.).

With such high SpO₂ levels to begin with, you can see how it is very easy to over-breathe and make your blood too alkaline under times of stress: you breathe in too much oxygen, and release too much carbon dioxide.

Your body can easily survive a low pH of around 6.8 without any lasting disturbances to your physiology. Intense exercise or long breath retentions can lower the pH of your blood, and you easily recover from it.

Respiratory alkalosis occurs when your blood pH level reaches 7.45 or above (Sampson, 2019). Your blood cells can quickly correct respiratory alkalosis by producing more acid. However, it is possible to have chronic respiratory alkalosis due to high stress levels or certain diseases that cause you to over-breathe. This is when your kidneys may also contribute to the balancing of your blood pH levels (this is called renal compensation) (Barker et al., 1957; Iftikhar, 2019).

Scientific Explanation Of Soma The Awakening Breathwork

The hardest imprints and traumas to clear are from your inner womb experience, to birth and then first 6/7 years of your life. Higher yoga practices were designed to clear this past traumas and negative conditioning so that you can become free and liberated.

The Awakening is a higher yoga ritual designed to clear negative imprints and help you break free from the past, so you can be more present, in the flow, liberated with the power to create your own reality.

The rhythmical breathing phase hyper-oxygenates the body, bringing in more oxygen and blowing out more carbon dioxide than normal. This alters the pH of the blood stream and creates a stronger electromagnetic field and current to flow through the body. The effect of this is an elevation of your vibrational and emotional energy. Through a higher vibration and emotional quality, negative emotions can be released and cleansed from the body, and the ability to attract and manifest your intentions is increased.

This type of breathing also moves the largest lymph gland in the body creating a powerful cleansing effect.

Before the breath retention phase you extend your exhale with deep vocal toning. This allows you to tap into the power of the vagus nerve, switch off stress and connect with your subconscious mind during the breath retention phase.

Life is a series of inhales and exhales, and when you pause your breath you press pause on life. Your quality of thought is also linked to breath. Erratic breathing leads to erratic thinking. Smooth consistent breathing leads to coherent thought – this has been shown by studies from Heart Math Institute.

When you pause your breath during the breath retention phase, you press pause on life. This allows you to go into the deepest meditative state possible where you can connect with your subconscious mind.

Using the power of affirmations, visualization techniques and self hypnosis you can program your subconscious operating system to influence your autonomic nervous system.

The activation of sexual energy throughout the process and the gradual progression of the experience through repetition of the routine over a 1hr duration creates a strong gamma wave stimulation and heightened ecstatic states of consciousness.

Powerful emotional releases can occur, negative imprints from the past can be cleared, and what we call ‘divine downloads’ that are moments of deep insight and moments of inspirations makes this experience truly unforgettable.

Holotropic Breathwork

This popular breathwork practice was founded by Dr Stanislav Grof and his wife in the 1970s. Dr Grof is a psychotherapist and the inventor of transpersonal therapy. He was one of the first people to use LSD as a psychotherapeutic tool. Holotropic breathwork is an “experiential method of self-exploration and psychotherapy” (Grof & Grof, 2010, p. 1).

How Does Holotropic Breathwork Work?

Holotropic breathwork is usually done in groups, using pair work where each person takes turns being the breather or the sitter. The process is guided by trained supervisors.

You breathe in with a powerful inhale through your nose, and then totally relax to release your exhale from your mouth without any force at all. There are no pauses or stops in the breathing – it’s a continuous cycle.

Holotropic breathwork incorporates a very dramatic music soundtrack that changes in mood quite frequently. This results in a very cathartic and sometimes psychedelic process where the participant may have dream-like visions, cry or laugh hysterically, experience tetany (severe muscle cramps), and have huge emotional release. There is also an element of bodywork involved, which Grof incorporates to help people release trapped energy and emotions in the body.

At the end of the session, participants are asked to draw or paint a mandala to visually represent any thoughts or ideas that came out of the experience.

Explanation Of Holotropic Breathwork

A possible explanation for the experiences participants report in holotropic breathwork is that it simulates a type of near-death experience, or out of body experience. This acts as a powerful trauma release. However some participants may leave the experience feeling more traumatised than before they did it. In various reports from Dr Grof’s own sessions, participants report sights of a white light at the end of the tunnel, or even communication with dead relatives. Grof reassures us that these experiences are harmless in the long term (Grof, 2015).

These effects may be down to a condition called respiratory alkalosis, which occurs due to hyper-oxygenation of the bloodstream as a result of exhaling too much carbon dioxide. Respiratory alkalosis is covered in detail later on.

It may also be that holotropic breathwork produces a stress response in the body which stimulates the reptilian and limbic parts of the brain. These areas deal with survival instincts and emotions.

If this part of the brain believes you are dying, it may reprogram the deeply hardwired instincts and imprints based around fear and survival, making you braver and more resilient. A similar “re-imprinting” effect is gained when you do something totally shocking and over-stimulating to the brain, such as jumping out of a plane at 30,000ft.

There has been plenty of research on the effects of holotropic breathwork over the years. Including using holotropic breathwork as an addition to psychotherapy (Rhinewine & Williams, 2007), effectiveness in helping recovery from addiction (Metcalf, 1995), and as a tool for personal and spiritual development (Cervelli, 2009).

Rebirthing Breathwork

Rebirthing breathwork was created by Leonard Orr, also in the 1970s and it is remarkably similar to holotropic breathwork in it’s effects, method and results.

Orr believes that through this breathing technique you simulate the feeling of being born from the womb and taking your first breath. This is supposed to help you overcome the most traumatic experience of your life – birth itself (“Discovery of Rebirthing Breathwork”, n. d.).

Orr was a student of Haidakhan Babaji, a satguru (supreme teacher) described in the book “Autobiography of a Yogi” as immortable and able to give gifts to anyone who can call his name sincerely (Yogananda, 2006). Orr considered himself one of those people, and believed he was given the gift of Rebirthing Breathwork. He believed it would be possible to become immortal in our physical bodies by using rebirthing breathwork. When his teacher Babaji died in the 1980s, immortality came under question (Dada, 2017).

How Does Rebirthing Breathwork Work?

Rebirthing breathwork is practically the same process to holotropic breathwork without the dramatic music. The emphasis is on the relaxed exhale. As humans we tend to force the exhale or breathe out with tension, but rebirthing tells us that the exhale should be as relaxed as possible to help release stress and tension from the body.

Explanation Of Rebirthing Breathwork

Leonard Orr has not spoken much about how his techniques work, or whether any health or psychological issues can be caused by frequently repeating the process in the long-term.

Equally, there is very little scientific research available on rebirthing breathwork. There is some research to suggest the activation of the autonomic nervous system during rebirthing breathwork (de-Wita et al., 2018). There is also research based on personal accounts of participants’ experiences (Carr, 2014).

As the techniques are so similar to those of holotropic breathwork, most of the same science could theoretically be applied to rebirthing.

Rebirthing breathwork has had negative media coverage after the death of a young girl. The unfortunate death was not a result of rebirthing breathwork, but of corrupt practice and abuse (Josefson, 2001).

Wim Hof Method

The Wim Hof Method has become incredibly popular in recent years. Wim Hof, AKA The Ice Man, created his breathwork methods after mastering Yoga and martial arts from a young age. His method was refined further as he cultivated his relationship with extremely cold conditions. Hof wanted to be able to stay longer in the freezing cold water as it had such a therapeutic effect on relieving his symptoms of depression.

The Wim Hof Method generates heat in the body and brings the mind to a place of stillness so that participants are able to control feelings of fear and stress that arise from being in such cold.

Hof has broken more than 20 World Records: several of them involving his ability to handle extreme weather conditions, proving scientifically that you can control your autonomic nervous system, by harnessing the power of breathwork and meditation (Kox et al., 2012).

What sets this method apart from Rebirthing and Holotropic Breathwork is that the Wim Hof Method is a daily practice, which takes 5-10 minutes to do.

How Does Wim Hof Method Breathwork Work?

The Wim Hof Method consists of 20-30 cycles of continuous connected breathing with no pauses between each inhale and exhale. Similarly to Holotropic and Rebirthing, the exhale should be very relaxed and participants should not exhale fully, but still leave some air in the lungs to breathe in more oxygen than you breathe out. Then, on the final exhale, participants empty their lungs completely and hold their breath for as long as possible.

Participants naturally feel an urge to breathe as carbon dioxide levels build up in the bloodstream, signalling to your brain that you need to breathe again. When the breath can be held no longer, participants inhale fully and hold their breath again for up to 30 seconds, squeezing the forehead muscles. The entire process is repeated for 2-3 rounds.

An important thing that differentiates the Wim Hof Method breathwork from Rebirthing and Holotropic breathwork is the breath retention phase where you hold your breath out for as long as possible, then hold it in for up to 30 seconds.

Explanation Of The Wim Hof Method

What sets Wim Hof apart from both Leonard Orr and Dr Stan Grof is his enthusiasm for trying to scientifically show exactly what is happening to the mind and body during the breathwork, as well as to explain why people get the health benefits they receive from daily practice.

Hof and his team are transparent in their research, and a lot of it is freely available on The Wim Hof Method website (“The Science Behind The Wim Hof Method”, n. d.).

Wim Hof has been criticised for over-stating the benefits of his breathwork methods and exaggerating the effects. Furthermore, critics who have tried to disprove his method have actually ended up becoming advocates of his breathwork techniques (“Testing The Ice Man”, n. d.).

His method has come under fire following the deaths of two people who practised the method and then submerged themselves in water (Caiola, 2017). It is strongly advised by the Wim Hof Method to never practise in water, nor to practice extreme methods without correct supervision.


Breathwork is different from Pranayama. No one really knows the true origins of Pranayama but it is at least 5,000 years old – perhaps even more than 10,000 years old depending on which historian you choose to listen to! However, the Yoga Sutras, from which Pranayama is based today, was first systemised and recorded by Patanjali around 200-300 BC.

In Sanskrit, Prana means energy and Yama means control, or restraint. Pranayama is a series of breathwork techniques, each with a different therapeutic purpose that is said to work through the control of energy in the body. Through Pranayama we learn how to become aware of this pranic energy and how to manipulate it in a way that is beneficial for cleansing and balancing the mind, body, and spirit.

There are many different types of Pranayama exercises, the SOMA Breath focuses on 7 exercises that have the most practical benefits for everyday life as well as evidence based research to support them. 

  1. Omkar: Chanting and extending the exhale with AUM mantra.
    For relaxation and cooling the body, preparing for Yoga asanas, and a useful exercise to help you get into flow state.
  2. Anulom Vilom/Nadi Shodhana: Alternate nostril breathing.
    To activate the whole brain, for relaxation, and preparing for Yoga asanas.
  3. Bhastrika: Bellow breathing.
    For energising the body and mind, cleansing the body, oxygenating the brain, and balancing the Ayurvedic Doshas (particularly Kapha).
  4. Kapalbhati: Rapid forced exhales while pulling in the abdomen.
    For getting rid of stale stomach gases, clearing the sinuses, increasing energy levels.
  5. Kumbhaka: Breath retention either on inhale (puraka/antar) or on exhale (rechaka/bahir).
    Promotes healing, deep meditation, builds CO₂ tolerance (when held on exhale).
  6. Ujjayi breath: constricting the throat to slow down and control airflow in and out of the lungs.
    For relaxing, relieving headaches, clearing sinuses, and cleansing the body of built up toxins.
  7. Kaki Mudra: Drinking Air
    For cleansing the bowels and promoting the growth of good bacteria, also reduces hunger pangs during a fast.

Nisshesha Rechaka Kumbhaka (nish-esh-ah – resh-ah-ka – kom-bah-kah) is an ancient Pranayamic technique. In Sanskrit, Kumbhaka (kom-bah-kah) means breath retention. Nisshesha Rechaka Kumbhaka means holding your breath (exhale) beyond the comfort zone. This is like the technique employed in the Wim Hof method, and it features in SOMA Breath techniques as well.

Explanation Of Pranayama

Pranayama techniques control air flow in and out of the body. Omkar, Anulom Vilom/Nadi Shodhana, Ujjayi, and Kumbhaka all create a slower rate of air flow, meaning CO₂ levels rise and O₂ levels drop. In the case of Kumbhaka, there is no air flow at all, resulting in a dramatic increase in CO₂ and decrease in O₂. Bhastrika and Kapalbhati are more energising, and create the opposite effects with a major increase in O₂ and decrease in CO₂.

The Pranayama techniques with the most significant health benefits and proven scientific research to back them up are Omkar, Anulom Vilom/Nadi Shodhana, and Kumbhaka. For example, there is research on the effects of Omkar on psychological, cardiovascular health, and also melatonin production (Harinath et al., 2004). Nadi Shodhana has been linked to pulmonary and cardiovascular health and to higher brain functions (Kinabalu, 2005) and shows positive results after 6 weeks of practice (Singh et al., 2011). Kumbhaka has a wealth of research behind it, including the effects of Kumbhaka on bronchial asthma (Murthy et al., 1984), improving sport performance (Hakked et al., 2017), sleep apnea (Chandra & Sharma, 2017), and more.

Bhastrika and Kumbhaka are used in the Wim Hof Method, which has a lot of research to evidence the health claims and benefits, as mentioned earlier.

Oxygen and Carbon Dioxide

The very fact they are focused on lowering O2 levels and rising CO₂ levels contradicts most of our modern ideas about the role and importance of oxygen to our health and wellbeing. This component of breathing and breathwork can come as a surprise to us. Our modern “common sense” understanding is that oxygen is good and CO₂ is bad. Ancient knowledge tells is that isn’t the case… at all. CO₂ seems to be central in unlocking our human potential.

How did we come to believe the opposite? Well, when we’re feeling stressed it feels good to sigh, doesn’t it? A deep breath helps us to relax. We also know that oxygen is essential to human life (so is CO₂, by the way). And let’s face it, holding your breath is not a comfortable experience. It sends your survival mechanisms into overdrive after just a few seconds.

If carbon dioxide is so good for us, then we should increase the CO₂ level in our bodies right now. Sounds simple enough, right? But it’s not that easy. 

Why do we struggle to get our CO₂ levels high enough to experience all of these benefits? Have we devolved somehow? Are we less resilient than our ancient ancestors?


Caiola, S. (2017). Breath-holding, meditation leads to two drowning deaths. Retrieved from http://www.capradio.org/articles/2017/07/28/breath-holding-meditation-leads-to-two-drowning-deaths/

Carr, E. M. (2014). Rebirthing: the transformation of personhood through embodiment and emotion (Doctoral dissertation).

Cervelli, R. L. (2009). An Intuitive Inquiry Into Experiences Arising Out of the Holotropic Breathwork Technique and Its Intergral Mandala Artwork: The Potential for Self-actualization(Doctoral dissertation, Institute of Transpersonal Psychology).

Chandra, A., & Sharma, M. (2017). Yogic Pranayama and PAP Therapy: Is There a Connection?. Journal of Clinical Sleep Medicine, 13(12), 1493-1493.

Dada, C. C. (n. d.). The physical immortalist and the guru who died: the relationship between Leonard Orr–originator of rebirthing–and his immortal guru Haidakhan Babaji.

de-Wita, P. A., Menezesb, C. B., Dias-de-Oliveirac, C. A., da Luz Costad, R. V., & Cruze, R. M. (2018). Rebirthing-Breathwork, activation ofthe autonomic nervous system, and psychophysiological defenses. Revista Brasileira de Psicoterapia, 20(2).

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Harinath, K., Malhotra, A. S., Pal, K., Prasad, R., Kumar, R., Kain, T. C., … & Sawhney, R. C. (2004). Effects of Hatha yoga and Omkar meditation on cardiorespiratory performance, psychologic profile, and melatonin secretion. The Journal of Alternative & Complementary Medicine, 10(2), 261-268.

Hakked, C. S., Balakrishnan, R., & Krishnamurthy, M. N. (2017). Yogic breathing practices improve lung functions of competitive young swimmers. Journal of Ayurveda and integrative medicine, 8(2), 99-104.

Josefson, D. (2001). Rebirthing therapy banned after girl died in 70 minute struggle. Bmj, 322(7293), 1014. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1174742/

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Murthy, K. J. R., Sahay, B. K., Sitaramaraju, P., Sunita, M., Yogi, M., Annapurna, N., … & Reddy, E. (1984). Effect of pranayama (rachaka, puraka and kumbhaka) on bronchial asthma. An open study. Lung India, 2(2), 187-91.

Rhinewine, J. P., & Williams, O. J. (2007). Holotropic breathwork: The potential role of a prolonged, voluntary hyperventilation procedure as an adjunct to psychotherapy. The Journal of Alternative and Complementary Medicine, 13(7), 771-776.

Singh, S., Gaurav, V., & Parkash, V. (2011). Effects of a 6-week nadi-shodhana pranayama training on cardio-pulmonary parameters. Journal of physical Education and Sport Management, 2(4), 44-47.

Testing The Ice Man. (n. d.). Retrieved from https://www.wimhofmethod.com/uploads/kcfinder/files/biology-now-chapter-22-Wim-Hof.pdf

The Science Behind The Wim Hof Method. (n. d.). Retrieved from https://www.wimhofmethod.com/science

Yogananda, P., (2006). Autobiography of a yogi. Los Angeles, Calif: Self-Realization Fellowship.