How to breathe, even if you've been doing it a long time

My guess is that you've been breathing your whole life. (Correct me if I'm wrong.) Another guess is that you've likely been breathing incorrectly your whole life. (I'd bet on that.)

Chances are that you're not using all your lung capacity, and probably never have. 

If your chest rises when you begin taking a breath, that's a sure sign of shallow, inefficient breathing. Another sign is if you easily run out of breath when you play.

If you're breathing correctly, your stomach pushes out, but your chest rises only when you've gotten near your maximum lung capacity. When both happen, that's correct breathing (which helps boost blood oxygen levels, by the way). If the only thing that happens is that your chest rises, it's not.

For almost all people, correct breathing is learned, not "natural". Most people never learn to breathe efficiently. It's a thing we have to practice until it's a habit. (I can't remember ever having a beginning student who breathed correctly at the start, and observing intermediate and many advanced players, correct breathing is usually rare. I've almost always had to teach students how to breathe.)

To develop correct breathing:

• Breathe from your stomach first so that your stomach distends, then "top off" higher up on your chest only if you need to.
  
  Do this all the time, even when you're not playing, until it becomes a habit.

• Especially if you're not clear about what "stomach breathing" is, lay on your back, put a book on your stomach, and breathe so that the book goes up and down as you breathe. (I suggest not using the A-E volume of the unabridged large-print Oxford English Dictionary.)
  
  Remember what it feels like, remember what your stomach does, and breathe the same way all the time, especially when you're in your normal playing position.

I have never known anyone who breathes correctly run out of breath playing most musical phrases! Yes, some medical conditions may decrease lung capacity, but people in decent health--preteen through advanced age--will not likely have a problem if they breathe efficiently.

There was a study done in the late '60s comparing the chest measurements of longtime wind players to those of non-players. The chest measurements for the wind players were several inches greater than for non-players, and though I'm not aware that the study was explicit about it, I'm pretty sure this is directly related to how longtime wind players breathe. 

Also, holding your breath will increase your lung capacity (but doesn't do much for you if you're not breathing efficiently).

<exhale>

B.