The breath and the nervous system

Recently I have been doing a little anatomy and physiology teaching for yoga teachers in training. The one question that always comes up is how does the breath calm the nervous system.

Firstly, yoga teaches us to breathe with intention, to be present and focused on the simple flow of an inhale and exhale bringing mindfulness into play. We therefore calm ourselves down, our mind quietens, we become less reactive and more focused. But there is a physiological response to this internal shift.

Vagus Nerve.jpg

This is a picture of the vagus nerve, (vagus meaning wondering in latin). These two branches of sensory nerve cell bodies wonder down to the gut and connects the brain stem to the body.

The functions contribute to both sympathetic nervous system (SNS, fight or flight) and the parasympathetic nervous system (PNS, rest and digest). The vagus nerve is the communication platform between the brain and the gut, the diaphragm muscles and provides some level of control for our heart rate viability (beat to beat intervals) by releasing a transmitter substance (ACh) and reducing the production of stress hormones (cortisol and adrenaline).

The SNS facilitates a slight increase to our heart rate during an inhalation. Whereas during an exhalation, the PNS stimulates the vagus nerve to secrete ACh.

So if we breathe with intention, learning to use our primary respiratory muscles (the diaphragm) by deepening our inhale and lengthening our exhale, we are not only slowing down our breath, we are stimulating our bodies to take a more restorative response, reducing the heart rate and increasing digestion.

By controlling the time we are in the SNS, we are also reducing the amount of stress hormones released (cortisol and adrenaline), both of which are contributors to inflammatory diseases such as arthritis, diabetes and coronary heart disease.

The Navy uses breath work to ensure a calm and focused mind before entering the waters. The USA Defence Dept are now teaching Army Veterans who suffer with PTSD simple yogic breathing techniques and as a study from Stamford research department has shown, it has offered huge relief for a large proportion of sufferers. Women in labour are taught to breathe. In fact, the breath is deeply embedded into the english language as a method to calm, who hasn’t heard the term ‘take a deep breath’?

Breathing isn’t rocket science, it is something that we do up to 24,000 times a day, it is also the only system in our body which we can and have the ability to control. And just 5 minutes a day to tap into our breath can have huge benefits on our mental, emotional and physical wellbeing.

Belly breathing

Belly breathing is easy to do and very relaxing. Try this basic exercise

Sit or lie flat in a comfortable position.

Put one hand on your belly just below your ribs and the other hand on your chest.

Take a deep breath in through your nose, and let your belly push your hand out. Your chest should not move.

Breathe out through pursed lips as if you were whistling. Feel the hand on your belly go in, and use it to push all the air out.

Do this breathing 3 to 10 times. Take your time with each breath.

Notice how you feel at the end of the exercise.