What's your lung capacity? I'm not taking Vo2 max or your O2 saturation's. Do you breath deep? Do you fill your lungs up at lest a few times a day. Inhale deep let that chest expand, then blow it all out.
Why, because it's good to breath deep. It allows you to see how shallow your breathing the rest of the time. Breathing deeply helps you remember how your core should feel and move. It can also teach you how to stay tight when you squat or lift, slam and Jerk!
Try on some oxygen!

Crossfit Total.

Back squat 185#

Press 95#(PR)

Deadlift 255#(but ugly for sure)