Breathing is the involuntary process of moving air in and out of the body. When you breathe in (inhalation), your diaphragm contracts (tightens) and moves downward. This increases the space in your chest, into which your lungs can expand. The intercostal muscles between your ribs also help enlarge the chest cavity. They contract to pull your rib cage both upward and outward when you inhale. When you breathe out (exhalation), your diaphragm relaxes and moves upward into the chest. The intercostal muscles between the ribs also relax to reduce the space in the chest cavity. This process is automatically controlled by a respiratory control center at the base of your brain.
It is thought that 70-80%+ of people breathe using their chest. Chest breathing tends to be very shallow. Deeper, fuller “stomach breathing” is more beneficial for the entire body: It opens the blood vessels deep in the lungs to allow more space for oxygen to enter into the blood, and essentially increases the maximum amount of oxygen you can inhale. It also eases pressure on the neck and chest muscles which would otherwise assume an increased share of the work of breathing. This can leave the diaphragm weakened and flattened, causing it to work less efficiently.
So we could say that “correct” breathing is stomach breathing; that is to say diaphragmatic breathing, as the diaphragm – not the stomach – is doing the work. With diaphragmatic breathing, the chest hardly moves at all. Instead, the stomach appears to be doing all the work. As mentioned above, with the increase in the amount of oxygen inhaled during diaphragmatic breathing, it is a great tool to have during physical exertion as more oxygen reaches your tiring muscles. When running for example, it may help relive runners stitch (reference 1).
To learn to diaphragmatic breathe can take some work. First we need to learn the skill in a non-exertion situation, before introducing it to your activity. The simplest, most common form of practice is lying on you back with a book on your stomach.
- Lie down on your back.
- Keep your upper chest and shoulders still.
- Focus on raising your belly as you inhale, seeing the book rise.
- Lower your belly as you exhale, the book falling.
- Inhale and exhale through both your nose and mouth.
Reference 1. Lore of Running 4th Edition, Tim Noakes MD
N.B. There are no ‘one size fits all’ style quick fixes in most injury scenarios, so these article shouldn’t be seen as such. They are merely guides to a better understanding of how our bodies work.