Volleyball players aren't always big, but they are definitely strong. For big and shapely that look strong the first I can think of is Ryoko Murakami. To me she never disappoints in the thick thighs genre.
Oh I got one.. she's only been in a few films and stopped but I was instantly intrigued by her thicknicity when she came out last year.. used to be a competitive swimmer. Maybe she went back *sigh*