Most of my early training was for track, and not bodybuilding. Years later I got back into the gym and liked the feeling of more mass, and the way it looked. The big guys in the gym were also a motivating factor - I wanted to look like them - life is too short to be small!
I took my first roids at 29. (Now 32). I wish I had started earlier! In my early twenties I had no contacts for getting gear and nobody to talk to about it - it was a taboo word in track (even though most of the best guys were juicing). Thank god for the internet and forums like this one.
While track was fun, if I could do it again, I would definitely choose bodybuilding instead.