Walker is a past student of the
St. Jago High School. Competing for the
Texas Longhorns women's track and field team, Walker won the
2005 NCAA Division I Outdoor Track and Field Championships in the
4 × 400 m relay. She won Gold at the
2008 Beijing Olympics in a new Olympic record time of 52.64 seconds. Walker won the Jamaica national championships in 54.70 seconds, narrowly beating newcomer
Kaliese Spencer and qualifying for her first
World Championships in Athletics. On 20 August 2009, she set the second fastest time in history of 52.42 seconds to win the women's 400 m hurdles final at the
2009 World Championships in Berlin. She leapt on the back of the mascot
Berlino the Bear to do a victory lap but Berlino crashed into a cart of hurdles and dropped her. ==Achievements==