Honestly, I rode my bike about a year and a half ago to work. On the way home, about half way I didn't know if I was having a heart attack or if my lungs hurt more then me not being able to catch my breath.

I was at about 300 then, I just bought a bike about two months ago, it took me a year and a half to forget about that trip enough to start riding again. Needless to say, I am at 235 now, and its alot more enjoyable then that particular 300 pound trip, lol.