Happens here and there. I usually get "I wouldn't wanna mess with you" or "you could play for the Cowboys" or "did you play football in college".
Older I get the less people care about that stuff. Most people are more concerned with where you work, what you do, how much you make, how long you've been married, how many kids you have, where you went to school and what you can potentially do for them.
People that want to get their bodies noticed tend to talk it up a bit on their own to get people going.
"I'm doin P90X". "I'm doin a Tough Mudder". "I train at Gold's." "Started my half marathon training last week."
Most folks are oblivious to such things.
For the majority, if you have only 12" arms, but have slight definition around the biceps you're "huge".