When I did my first Meditation Made Simple course™, I also learned some breathing techniques. Now I had to conciously focus on my breathing, and something that without thinking (unconciously) went relatively smoothly, suddenly was really hard.
The breathing rhythm my body was used to, was not the rhythm I had to do in the exercise. My God, I could hardly catch my breath. This wasn't relaxing, this was pure stress!!!
After living for years in fifth gear (which was the whole reason I wanted to learn to meditate), my breathing apparently was also in fifth gear. Abdominal breathing, something you see every baby do and what is your natural way of breathing, didn't feel natural to me anymore. After every 3 abdominal breaths, I quickly did a high breath where I pulled up my shoulders and expanded my chest. Pffff....air!!! This exercise felt so unnatural, it was like learning to write left-handed when you are a right-handed person.
The breathing of most of us is too shallow and too fast. Our lungs do not fill with enough oxygen and we do not eliminate enough carbon dioxide. The result is that our cells don't get enough oxygen and we build up a toxic load in our lungs. The energy we feel in our body is caused by the vitality of our cells. Also a high and shallow breathing means that we don't use the full capacity of our lungs, which causes them to lose some of their ability. In the long run it causes us to lose more of our vitality/energy. Animals that breath the slowest, live the longest. A great example is the elephant.
Modern science argees with the yogi's concerning shallow breathing. An article in the "Journal of the Royal Society of Medicine" states that quick and shallow breathing can cause fatigue, sleeping problems, anxiety, stomach problems, heartburn, bloating, muscle aches, dizzyness, visual problems, chest pain and heart palpitations.
That doen't sound all too great. Thankfully we can do something about that...breathing slower and deeper!
Nowadays stress mostly lives in our mind.
The technic I like best is the "Diaphragm Breathing". The Diaphragm is a C-shaped structure of muscle and fibrous tissue that separates your lungs from your abdominal. When you breathe out, it is shaped as a dome and when you breathe in, it pulls your lungs full with air pushing against your intestines and causing them to push your belly out. This breathing costs the least energy because you only use one muscle compared to the high and shallow breathing, where you use your intermediate rib-, schoulder- and sometimes your neck-muscles. People with neck cramps now know what type of breathing they do...
With this breathing technic you concentrate on your diaphragm. You push this muscle as much down as you can. (When you have no idea how to do this, sit up straight and push your belly out. Feel the muscle you're doing it with...that's your diaphragm muscle). If you can't push it any lower, breath out by pulling your belly in and your diaphragm pushes the air (carbon dioxide) out of your lungs. At the end you push a little bit more like there is no more air in your lungs (in a relaxed way, not like you got pushed in the gut). When you repeat this a couple of times, you'll feel your body relax and your focus will leave your mind and be on your body/breathing. The more you'll practise this, the more you'll notice that your shoulders and neck will be relaxed and less cramped.
Just like learning to walk, which in the beginning you do fully conscious until it becomes a habit, abdominal breathing became a habit for me after I practised it often enough. Which kept my blood pressure low and me feeling relaxed. But with 3 kids my life is not always calm and there are times when I do end up in a "fight-or-flight" situation. My adrenal glands produce cortisol and adrenaline which cause my bloodpressure to go up and my breathing to become shallow. And sometimes that is necessary, there is a reason nature built us like this. But nowadays stress mostly lives in our minds. My kids are no sabertoothed tigers... And in these situations, I focus on my diaphragm breathing and calm down.
And like with everything: the more you do it, the easier it gets. Look, we don't have to become an elephant, but the breathing and power of that animal seems kind of great.