Dempsey put together an illustrious track career at Georgia Tech and Alabama A&M. At Georgia Tech, Dempsey was a four-time All-ACC selection in the 100 and 400 meters, as well as a member of the 4x400-meter relay. She holds the ACC and Georgia Tech record in the 100 meters and the 4x400-meter relay in indoor and outdoor competition. She was a three-time NCAA qualifier in the 400-meter dash and the 4x400-meter relay. In 1992, Dempsey was a U.S. Olympic trials qualifier in the 100- and 400-meter hurdles. At Alabama A&M, she was a 1994 All-Cross Country selection and a two-time NCAA qualifier in the 55-meter hurdles and the 400-meter relay.

Dempsey was an assistant coach at Morehouse College from 1994-1994. She also had other coaching stints at Bob Jones High School and was head coach at Spelman College. She came to WVU in 1998, with her primary responsibility being to work with jumpers and hurdlers while also assisting with recruiting, travel coordination, and other administrative duties.