Paul Ryan may have had trouble strong-arming his way through this week’s Vice Presidential debate against incumbent Joe Biden. But he made a solid attempt to flex his muscles, figuratively and literally. In those infamous photos pulled from TIME’s archives and published yesterday right here on our LightBox blog, Ryan shows off his dedication to fitness. David Letterman skewered the Wisconsin congressman in his daily Top Ten segment, wondering what was going through his mind as he posed for the pictures last year.