I did the longest running mountain bike race yesterday in the State of Michigan at Pando Winter Ski park. Check that, I did 20 min of a race, before a flat tire ended my day early. Lack of air really sucks. It took me about 45 min to walk my bike back out of the course.
That is a long time to think. Air is crazy important. I had been training correctly, my hydration and nutrition were in check, my bike was ready. No air.
This could be the same thing with our bodies. Your sleep is solid. Nutrition is top notch. You do the right exercises. Your programming is smart. You suck at breathing though. Pretty common.
The more I see people with anything that gives them pain or decreased performance the more I find that they don't really know how to use the diaphragm. They don't know how to get air. They can brace, but not breath. They can breath, but not brace.
They can breath and brace until they are tired. Then it all goes back to chest breathing and shoulders coming up like they are shrugging trying to breath.
Air is important. You won't go far without it.