Play video content EXCLUSIVE

He's a 4-time Mr. Olympia ... he's got 21-inch biceps -- so you'd have to be an IDIOT to challenge Jay Cutler to an arm-wrestling match on the street ... right?

Well, good news ... we've got that idiot!!!

All 275-pounds of Jay Cutler were out in NYC the other day ... when our TMZ Sports photog (who's been working out btw) decided to challenge the guy to an "Over the Top" style showdown.