I have been a moderate runner (usually 2-3 miles about 3 times a week) for several years now. I frequently experience difficulty breathing when I run, in the form of chest tightness and mild wheezing that persists for 30 minutes or more after exercise. This occurs both indoors and outdoors, in warm and cold weather, and whether I've run the day before or not run for a week or more (although I have figured out that I'm more susceptible to breathing problems when it's cold, and when I have NOT run the day prior).
There's a lot of inconsistency - sometimes I run quite easily with no problems breathing whatsoever, and sometimes it feels as though my lungs still aren't warmed up after 30 minutes! Occasionally I can "force" myself to stay it out, try to yawn as I run, and keep going, but sometimes I just can't.
Is this asthma? What can I do?