Hi Peter,
Yes breathing is an important part ! There are 2 schools of thought 1) that you synchronize your movements with your breathing, using your breath as the guide and 2) that you do the movement and over time your breathing adapts to the correct pattern.
They both end up the same !
There are also different types of breathing and types of exhalation
I would suggest a gradual process that can be developed at your own pace.
First take a deep breath and notice which part of your body expands.
You want the belly (diaphragm) to expand and to be relaxed. This is always the case to start with. If you follow the breath with the mind you are leading the qi down to the dantien (between 2/4 below the navel and inside the body).
Then breath out and pull the belly in and slightly tighten the abdomen and perineum. This is qigong 'natural' or 'Buddhist' breathing. It helps the internal organs, the heart and depending on the amount of tightening, the stomach muscles. You could even tighten the whole body on the out breath but be aware that it is a little dangerous and raises the blood pressure.
This is not the breathing you want for playing ilc
But it helps to get the mind and breath to the dantien and is the crux of many styles of qigong and 'external' kung fu. Do this breathing intentionally twice a day for at least 20 mins and you'll have optimum health (that's a liable claim
).
Next is 'reverse-breathing' and again there are variations. In ilc this is emphasized in the 'tu-na breathing', it is so important that it is one of the 15 and the first movement of both the forms !
It is the same in breath as before. The out breath is different in that rather than tightening, you stay relaxed and 'drop' the breath so that you feel a sinking from the sternum to the dantien and the lower belly expands a little more. At the same time there is a sensation of expansion up the back, the lats and out to the fingers. Yin down the front and yang up the back.
I practice both. To me the first is collecting and storing the qi and the second is moving it around the body, the yin and yang of breathing
I use the first for running and cycling so I can get enough air into my lungs and it seems to make them both more meditative and qigong.
As to food and sleep, well I was vegetarian for a few years but now eat meat and I seem to need 7-8 hours of sleep to stay well. There is so much conflicting advise that i try just to not eat too much and eat a varied diet ???
???
stay well, train hard
Steve