Written by Sylvie Le

The most important thing I learned in the first yoga classes I ever took was not how to work with the body or even the mind, but the power of a good, long, deep breath.

I now know why working effectively with the breath – whether that’s just improving how you breathe on a day-to-day basis, or using specific breathing techniques – is literally transformative. It affects important systems in the body that influence us physically, emotionally and psychologically.

In yoga, pranayama, Sanskrit for ‘breath control’, is the name given to a range of breathing practices. It’s mentioned in key yoga texts, from the Bhagavad Gita to Patanjali’s Yoga Sutras, and traditionally pranayama was a much more central part of yoga than the physical asana. Consciously working with the breath to influence the body and mind has been practiced by yogis for thousands of years, but in the past decade or so there has been a rise in medical and scientific research which explores how breathing can improve health.

This interest in the breath has definitely trickled down to mainstream media. Nearly every day I read something along the lines of how scientists are rebranding traditional pranayama techniques, how navy SEALS use specific breathing patterns for stress reduction and clarity, or how iceman Wim Hof has popularized certain pranayama practices.

But you don’t need fancy techniques, or even need to know the science of why influencing the breath has such a big impact on our physical, psychological and cognitive functioning. Before I was aware of this research (or I was even interested in it) I knew, from experience, that breathing with awareness was powerful.

In that vein, this post has two parts. The first part covers some of the science of breathing, and the second part is a very simple and accessible breathing technique. Feel free to skip to the last section and practice this breathing technique, it takes less than three minutes. But if you would like to know more about what’s happening in the body, read on!

The Nervous System: Stress and Relaxation

Meditation Deep Breathing

The nervous system is one of the body’s primary communication systems. When it comes to the breath there is one specific branch of the nervous system that is important to understand: the autonomic nervous system (ANS).

The ANS controls the internal bodily processes and organs that we have no or very little conscious control over, such as heart rate, digestion, temperature, the need to go to the bathroom, and breathing.

The ANS has two key divisions: the sympathetic nervous system (SNS) and the parasympathetic nervous system (PSNS). You might know these already as the fight-or-flight response (SNS) and the rest-and-digest mode (PSNS).

Fight-or-Flight vs Rest-and-Digest

When we are in a stressful situation the SNS kicks in – heart and breath rate increases, we are more alert, and our muscles start to activate, whilst unnecessary energy-consuming bodily functions, such as digestion, are suppressed.

This is helpful for genuinely life-threatening situations, but we are not primed to spend large amounts of time in this heightened state. Many of us operate at a low level of chronic stress a majority of the time which is detrimental to our physical, emotional and psychological wellbeing.

We should, instead, be spending most of our time the PSNS, which governs the body in regular states, ensuring good digestive function, quality sleep, and in general greater wellbeing.

So how can we reduce stress, and make sure our PSNS is dominant? I think we all know that telling ourselves to ‘relax’ doesn’t work. We need to find a way to communicate directly with our nervous system, but we can’t just instruct the heart to slow down or our gut to digest properly. But we do have one ANS function we can easily access and influence: the breath.

Due to the structure of the nervous system, largely due to an important nerve called the vagus nerve, if we influence the breath we can activate our rest-and-digest state.

The Vagus Nerve

Meditation Deep Breathing

Research into the vagus nerve is on the rise, ever since vagus nerve stimulation was found to effectively treat a number of neurological disorders, including treatment-resistant epilepsy and depression. However, the influence of the vagus nerve extends far beyond the brain and has a much broader impact on the body.

What is the Vagus Nerve and Where is it Located?

The vagus nerve is the longest cranial nerve (CN X) in the body, which is where it gets its rather wonderful name from. Vagus, is the Latin word for ‘wandering’, because the vagus nerve wanders through the body:

It starts in the head and then meanders down through the chest, innervating the heart and lungs, before heading down into the abdomen and innervating many of the digestive organs. An influential paper on the gut-brain connection outlines how stimulating the vagus is an effective treatment for both psychological and gut-related disorders, as well as inflammation more generally.

Not only does the vagus nerve connect our head, heart and gut, but it is the main nerve of the parasympathetic nervous system.

Stimulating the Vagus Nerve

Stimulating the vagus nerve is a way to activate the parasympathetic nervous system. Although some of the research I have cited uses specific medical devices to stimulate the vagus nerve, we all have our own inbuilt stimulator available to us at all times: the breath!

There has been extensive research, outlined in this 2018 review paper, on how different contemplative wellbeing practices, including yoga and Qigong, that have an emphasis on the breath lead to stimulation of the vagus nerve. The paper documents physical benefits from heart health to decreasing inflammation, mental health benefits, as well as cognitive improvements from attention to creativity.

Diaphragmatic breathing: Stimulate the Vagus Nerve Using the Breath

Meditation Deep Breathing

A method of breathing, sometimes called diaphragmatic breathing, is a way we can stimulate the vagus nerve using the breath. All breathing is technically diaphragmatic, but what this term refers to is a conscious lengthening, slowing down, and deepening of the breath.

The vagus nerve is stimulated both when the breath rate slows down (i.e. you take fewer breaths per minute), and also on the exhale. This is why you might work with a breathing ratio in your yoga class, perhaps inhaling for a count of four and exhaling for a count of eight.

Although the intention of diaphragmatic breathing is to breathe as deeply as possible, the breath should not be forced. If you modulate the breath in a way that feels uncomfortable or restricted, you are likely to trigger a stress response in the body. Just the act of simply bringing awareness to the breath can modulate it enough to activate the PSNS.

Diaphragmatic Breathing Exercise:

Meditation Deep Breathing

Have a go at this simple breathing exercise right now.

  1. Check you are sitting comfortably, shoulders soft and spine long.
  2. If you like, place your hands on the belly.
  3. Become aware of the breath. You can inhale and exhale through the nose, or inhale through the nose and exhale through the mouth. Whichever you prefer.
  4. See if you can get the breath to expand into the belly, without forcing it. If this feels challenging in any way, just focus on finding a tiny bit more space in the torso by using the breath, it doesn’t need to reach the belly.
  5. Perhaps the breath expands into the sides of the body and the lower back too. Maybe you can comfortably fill the belly and keep expanding the breath into the ribcage, all the way up to the collarbones.
  6. Notice the very end of your exhales. Is the exhalation as complete as possible, or are you holding on to some of your inhale? Let your inhales be long and deep, and your exhales be slow and complete.
  7. Take five breaths like this.

I hope this was helpful (and relaxing)!

You might want to start a dedicated daily breathing practice, it can easily be integrated with a meditation or yoga practice. You can do this breathing exercise standing––perhaps before your sun salutations, seated––at the start of meditation, or lying down–– for extra relaxation.

I often recommend doing this exercise lying down, with a pillow underneath the knees. Not only is it extra relaxing, but it ensures the spine is in good alignment. It can also be nice to place something slightly weighted on the belly, like an eye bag or a light book. If you have insomnia I also really recommend this practice. You won’t always fall back asleep, but you will still be encouraging the body’s natural resting state.

Although it’s nice to have a designated time and space to really let yourself soften fully into the breath, you can do a version of this literally anywhere! Next time you have road rage, try taking just one big inhale and sighing the exhale out. In an exam or work presentation, just notice how you are breathing and consciously slow it down for a few breaths –– nobody will know what you are doing, but it could help with both calm and clarity.

There are a lot of fancy breathing exercises and ratios you can explore, but when it comes to the breath I have always found that simplicity is key.

Sylvie Le, DPT, PYTC