When asked if the noises she makes on the courts, also known as her grunts, distracts quieter opponents, Serena Williams responds that she's always been curious about that as well.

"I'm thinking like we were playing just recently in the finals and Venus and I were grunting really loud in the doubles and the other girls weren't doing anything," she added. "And after the point, I was thinking, 'Wow, that was pretty loud. Was that distracting for them?"' -Serena Williams quoted by The Canadian Press

Serena draws much of her inspiration from one of her tennis idols, Monica Seles. She states that when she used to watch Seles play, she was one of the first to have a loud and hard grunt on the courts. Williams also told Letterman that she models her grunt after Seles'.