I get the damn colds, too, and they sometimes morph into bronchitis. I work outside, (yeah, I know it doesn't really get cold here), and I ride year-round, even when I'm sick.
Have been to different doctors, they are rarely any help. Usually they just tell me to wait and get over it, sometimes they will prescribe antibiotics.
I think doctors see so many people who are all effed up from smoking and obesity when they see someone my age (61) who is active and relatively healthy they don't get alarmed by a cold or respiritory infection.