I found this a strange subject, because, (1) most BBs have trouble with calves being too small, and (2) for me, a large gastroc in women is beautiful (too many women have ugly, scrawny calves, which is a real problem with light women BBers--'course, that's just me, and not the average judge).
I disagree with an earlier poster. I think fast cadence cycling 50+ miles a week can actually reduce the circumference of the calf.