Usually I find, when I breathe shallow, there are three reasons for this:
1) The muscles on the neck, shoulders, back and stomach are tense, thus constricting the inhalation and the work of the diaphragm. In some cases it needs a massage, but mostly just gentle stretching exercises like the ones integrated in the program (look quote below) suffice. Then I am able to breathe more freely and deeply.
PerfectCircle said:
Hi there!
Here is the link:
http://eiriu-eolas.org/online-version/
On first video after you choose a language, you click on Practice and then Stretches and that's it.
2) Having not done proper deep breathing with the diaphragm for a while, thus having had less training of that muscle, can also contribute to shallow breathing. So I think, by training in the way like Oxajil explained and quoted above, as well as with time, you may arrive at deeper breathing eventually.
3) Having fallen back into the habit of shallow breathing after EE (which we all have acquired more or less thanks to stressful events especially in early life, and which we automatically used as an opportunity to numb deeper and intense emotions as far as I know) while going around on daily business. This can be related to a lack of awareness, due to being consumed in the activities of everyday life. Thus I think, being aware of our breathing if possible - or better, making deeper diaphragm breathing a habit - can help in this regard.
Also the fact that we spend a lot of our current lifestyle on chairs and often not sitting straight might contribute to shallow breathing.
I am thinking about two Sott articles here. One is about the
Psoas muscle and how it relates to our breathing. It looks like shallow breathing can also be contributed to by a constricted Psoas muscle. Some quotes from the article:
[...] The psoas is the principal muscle associated with physical stability. It stretches from the legs to the spine and is the only muscle connecting the legs to the spinal column. The muscle flares out from the T12 vertebrae, follows down the five lumbar vertebrae, before attaching to the top of the thigh bone.
[...] In addition to connecting the legs and spine, the psoas is connected to the diaphragm. Breathing is modulated at the diaphragm, and it is also the location where many physical symptoms associated with fear and anxiety manifest. Koch believes that this is due to the direct link between the psoas and the most ancient part of our brain stem and spinal cord, called the reptilian brain. {Thinking about the vagal connection here}
[...]This lifelong chronic stress put on the psoas can lead to many problems like back, hip, or knee pain, and even digestive issues and dysfunctional breathing. It could also be a major cause why people suffer from chronic physical pain.
[...]Lengthening and releasing your psoas grounds you to the Earth, which is filled with healing and revitalizing energy, thus allowing you to balance your pranic energy and enabling you to feel more present in the moment. Proper structural stability attributed to a healthy psoas allows prana to flow, unimpeded, throughout the body, allowing for proper distribution of vital energy. In the physical sense, when the body can properly support itself, movement is less-restricted and requires less effort, thus leaving you more energetic. [...] {Deeper breathing can then be possible}
The second article I have in mind is about the
Science of Breathing. It is basically about Pranayama - breathing properly (which is something we all are re-learning) and with awareness. Maybe you can draw some useful information for yourself from there as well.
Just some thoughts and info - hope they help. In the end, I think, being gentle with yourself (in getting used to deeper breathing while not forcing the body) and patience will pay