I'm convinced it's just genetic. I'm sure I could spend the next four years doing weighted calf raises every day, eating like a pig and maybe I'd get an extra inch or so around, but for all the various types of legwork I've done over the years, none of it's made a difference. There was a girl I used to work with who had monster calves, and the only exercise she did was yoga. I don't even bother working calves anymore, it's so discouraging spending months on them and seeing zero results. Can't help but be self-conscious when wearing shorts though.