Running for the University of Wisconsin, Favor became the first athlete of either sex to win the NCAA outdoor 1,500-meter/1-mile championship four times, from 1988 through 1991. She was also the 800-meter champion in 1990.

At NCAA indoor meets, Favor won the 1-mile in 1987 and 1989, the 1-mile and 3,000-meter in 1990.

The 5-foot-3, 110-pound Favor won the 1990 Honda Broderick Cup as the nation's outstanding female collegiate athlete. She was named the Big Ten Conference's female athlete of the year three consecutive times, 1988 through 1990, and the conference's female athlete of the decade 1981-1991.

As a collegian, Favor won 54 of 56 races, including 40 consecutive finals. She also won national championships in the outdoor 1,500-meter in 1990, 1991, 1998, and 2003 and the indoor 1-mile in 1991, 1998, and 1999.

She has been on three Olympic teams. After missing most of the 1999 outdoor season with an Achilles tendon injury, she had an outstanding year in 2000, running the world's fastest time of the year in the 1500-meter. Favor was leading with about 200 meters to go in the Olympic finals when she collapsed to the track because of a hamstring injury and dehydration from anti-inflammatory medication. She managed to get up but could finish only twelfth.

Favor had hoped to make the Olympic team for a fourth time in 2004, but she was forced to withdraw from the U. S. trials because of a torn hamstring.