I am new to the forum but not new to running, I am starting a run group at work in April, I've been running for 16 yrs. I remember starting out and having issues with the "breathing" technique, I'm here to say stop focusing on your breathing and focus on your running technique, I breathe through my mouth when I run, I keep my shoulders back and arms swinging at waist, doing this keeps lungs open, lots start out with arms high up and slouched over this binds your lungs and it feels like your struggling to breathe, relax and just breathe. Hope this helps