How we breathe influences Oxygen (O²) transfer from our blood to our muscles and organs. Haemoglobin is the protein molecule in red blood cells (erythrocytes) that carries O² from the lungs to the body’s tissues and organs and returns Carbon Dioxide (CO²) from the tissues back to the lungs
The air we breathe contains 21% O². The bloods’ O² saturation (SpO²) is a percentage measure of the Haemoglobin carrying O². In healthy individuals, the SPO² is between 95 and 99%. This percentage can easily be measured with a simple Pulse Oximeter. Some Pulse Oximeters are also able to measure the Haemoglobin in the blood.
Of importance is to ensure that the O² is delivered to the muscle and organs. Endurance athletes rely heavily on O² to produce energy through the aerobic (with O²) energy system. Therefore, the more efficient the O² transfer to the muscle, the better the athlete can harness this energy.
Carbon Dioxide (CO²) generally considered a waste gas, is a vital ingredient for efficient O² transfer. CO², together with heat and 2,3-DPG, regulates haemoglobin’s affinity for O². This is known as the BOHR effect and demonstrated by the Oxyhaemoglobin dissociation curve.
The slightest change in these vital ingredients has a significant effect on O² release. A lack of adequate CO² in the blood, caused by hyperventilation, is considered a breathing pattern disorder. One such disorder can be as simple as chronic hidden hyperventilation or over breathing, reducing the CO² in the bloodstream.
Dysfunctional breathing patterns in individuals is measured using several tests. One such test being a Voluntary Breath Hold Test (BOLT) that is thought to provide an indirect index of sensitivity to CO² build-up. Holding of the breath until the first definite desire to breathe is not influenced by physical training or behavioural characteristics. Instead it can be deduced to be a more objective measurement of breathlessness. (Nishino, 2009).
Slowing and minimising breathing as well as breath hold exercises reduces the sensitivity to CO² and breathlessness. We can breathe less and achieve better oxygenation.
The Biochemistry of the body is targeted through these exercises to evoke adjustments of breathing patterns. Functioning of the Autonomic Nervous System comprising the Parasympathetic and Sympathetic Systems, is improved. The Vagus Nerve controls the functioning of both systems. It is part of a circuit that links the neck, heart, lungs, and the abdomen to the brain. The Sympathetic (Fight or Flight) response is instinctive and reduces blood flow to organs not required for this purpose. The Parasympathetic (Rest and Digest) response is responsible for improved blood flow to vital digestive organs and the brain.
Both the Sympathetic and Parasympathetic Nervous Systems have a role. However, slow nasal and diaphragmatic breathing triggers the Parasympathetic System thereby downregulating the body after intense exercise or a fight or flight response.