At the 2008 Olympics in Beijing, China, she advanced to the semifinals of the women's 100-meter butterfly, and finished seventh in the final of the women's 200-meter butterfly.
She earned a silver medal by swimming for the second-place U.S.
team in the preliminary heats of the women's 4×100-meter medley relay.Breeden attended Stanford University, and swam for the Stanford Cardinal women's swimming and diving team in National Collegiate Athletic Association (NCAA) competition from 2007 to 2010.
As a college swimmer, she was a three-time NCAA national champion in the 200-yard butterfly (2007, 2009, 2010), as well as the NCAA champion in the 100-yard butterfly (2010).