100% serious, he did. Repeated it several times as a kind of running "laugh" throughout the seminar to...like at the end of a totally unrelated question / answer he would add "...and a Doctor who's a Bodybuilder" at the end...lol.
He also discussed his blood work while off and on cycle etc and how his health markers varied depending on what he was using at the time. No details as such but did say that he was healthiest in the weeks prior to a show??
Cheers,
G