Athletics (Women's 400m Hurdles)
She crossed the line in Beijing to claim gold and a new Olympic record of 52.64 seconds.
Walker's 52.42 seconds to win gold at the 2009 World Championships in Berlin was the second fastest time in history.
Did you know?
She can run as fast as she likes, but most people will probably know her best for being unceremoniously dropped by Berlino the Bear the mascot after she jumped on his back for her lap of honour in Berlin.