Breathing is important because it allows our body to move and function on every level. The diaphragm, a sheet of muscles across the bottom of the chest, is important as it expands and contracts the lungs to pull in and expel out air.
Breathing is part of the autonomic nervous system which predominately controls vital functions such as the heart, and digestion. This is mainly done unconsciously. However, breathing is one part of this system that we can actually control at will. As a result, it can be used to reduce stress especially through many aspects of Yoga, in particular, meditation, relaxation and breath control (pranayama).
Our breathing works in tandem with our heart and when our breathing pattern changes, our heart’s activity does too. For example, it will slow down when we practice deep breathing, which triggers the rest and repair response in the nervous system.
Furthermore, slow deep Yoga breathing brings back online the part of the brain associated with rationality, focus, concentration, emotional control, and hence the ability to create a relaxed mental state.
Those who suffer from being in a constant stressed state are not in rest, digest, and repair mode. This repair mode is important because it affects the wear and tear of our bodies, and is essential in protecting us from heart disease, high blood pressure, depression, and anxiety.
Stress is associated with creating large imbalances in the brain’s chemical messaging system associated with relaxation, sleep, and muscle function. Too much stress triggers inflammation in the nervous and immune system and is the cause of many auto-immune diseases such as MS, arthritis, and IBS.
In relation to our stress response, the Vagus Nerve, important in helping to make our nervous system function, has been linked to health conditions from low mood to chronic disease. Good vagal tone is linked to physical and psychological well-being and is regulated by many Yogic practices.
The more important point to make, is that stress often begins in the mind: “Every mental state creates a corresponding state in the body, and every action in the body has its corresponding action on the mind” (Swami Vivekananda).
Therefore, the ultimate goal of Yoga is to settle mental disturbances (Yogah chitta-vrtti-nirodhah, The Yoga Sutras 1:2) and this can be done by regulating the breath consciously, which helps to quiet the mind by cultivating present moment Mindful attention.