More Muscle for the Bustle

The expression used to describe a woman with an exceptionally muscular butt. I similar phrase to "more cushion for the pushin" but instead of cushion (fat) she has hard muscle. Pain from thrusting during intercourse is implied. Serena Williams is the perfect example of this phenomenon.

Stan: Dang that female weightlifter has a big manly booty!

Dave: You know what they say, that's just more muscle for the bustle.

Stan: I bet her boyfriend can't feel his front half for a week after doggy style.