Honestly? A lifetime of propaganda (a lot of it from jewish movies/tv) saying stuff like:
>study hard, be nice, learn to play piano (no joke), etc. and you will get a great wife & family someday
>going to the gym before you're 18 will damage your bones permanently
>"you don't want to be a meathead jock, be smart/educated and you'll be successful"
etc. etc. from movies, parents, relatives, basically everyone except chad, who probably would've told me the truth if I had thought to ask.
I still did a lot of cardio, but girls don't give a shit about cardio.