Serena is no more muscled than the female sprinters. Have you really looked at the way she is built? Don't understand how there can be ANY question - she has a big chest and a big butt. She was totally dominant. The rest of the women on the tour better step up their games or hope this is just a phase and Serena comes back to earth soon. I don't think she can keep up this level of play indefinitely. Personally, I hope is lasts through the US Open.