I have severe asthma, but feel exercise helps me control it. Like you I am a mouth-breather when I exercise, I just can't get enough air in through my nose. However, I am on Symbicort for my control inhaler, and what a difference it makes. It works much better than anything I have ever used. I still get the throat burning and tightening in the winter though. I agree it does suck, but I just power through it and eventually I can handle it. It is certainly an uncomfortable feeling though.