ZenS - having difficulty breathing while riding may be "normal" for you, but it IS NOT NORMAL. Trust me on this, I've been there. I went undiagnosed most of my life. I always knew I couldn't run and breathe at the same time. People just told me I was out of shape. No, I was out of air. It really angers me how I got poo-pooed. It wasn't until I was bike riding on the levee, in my 40s with some folks that actually cared and had a really hard time breathing - I mean struggling to breathe at 12 mph - resting, then riding back to the office, with an escort, at 10 mph, which was all I could manage without my breathing getting out of control.

Breathing like a freight train is not normal.

Fortunately I had a doctor that took me seriously AND exercise was important to him. Not moving was not an option as far as Dr. R was concerned. I take an inhaler twice daily and another one before I ride, or any form of hard exercise.

Do you hurt around your sternum or upper chest? I wasn't prepared for how much asthma attacks HURT.

Please, see a doctor. Find one that takes you seriously. There is a breathing stress test they can do to you. I have normal resting lung capacity, not so normal under stress.