Stereotypically old is probably what I'd consider if all I have to go by is looks. Like the kind of person I'd expect to be walking around with a cane. Except this old looking guy was probably in much better shape than I am.

I would have to plead ignorance on the other question although I would believe that the term came from the fact that older persons statistically have a greater chance of losing control of certain bodily functions that lead to the coined term "old fart". Although if anyone out there knows any better, prove me wrong.

Never underestimate those who are over 70, even if they look the age...