Whenever we use the term deep breathing, it indicates a way of breathing that leads to relaxation. Deep breathing techniques are usually a quick way ofrelaxing by focusing the attention on the breath, along with increasing the length of inhalation and exhalation.
There are two main deep breathing techniques. The most important one is diaphragmatic breathing, also called belly breathing. Here, we concentrate on the movement of the abdominal wall, which moves outward with inhalation, and moves inward with exhalation. We can benefit greatly by slowly increasing the length of inhalation and exhalation, which leads to the decrease in respiratory rate. This not only reduces the workload of the heart and lungs, but also results in mental relaxation. Most of us are predominately chest breathers, leading to strain on our body systems, especially the heart.
The second type of deep breathing is called total breath, also known as yogic breathing. This consists of all three types of breathing-Diaphragmatic, Chest and Apical breathing. This form of breathing needs to be worked on, in order to increase the length of exhalation. Most of us have a much shorter duration of exhalation in comparison to inhalation, when the ideal ratio between inhalation and exhalation is actually 1:2.
Deep breathing techniques result in a much better ventilation perfusion ratio, leading to better oxygenation at the cellular level, as well as better removal of toxins from the body in the form of Carbon Dioxide. They are also responsible for physical and mental relaxation, because they contribute to the predominance of the parasympathetic nervous system.
Thus deep breathing techniques help in better oxygenation, efficient removal of toxins and deep relaxation.