Parker was a member of the Essex Ladies Athletics club (now
Woodford Green with Essex Ladies). In 1983, she won the AAAs National Under 17 title in the 400 m hurdles, running 62.37. Her senior breakthrough came in 1990 when she finished second at the
AAA Championships in 57.43, behind
Gowry Retchakan's 57.14. This performance earned her selection for the
European Championships in Split, where she ran 56.84 in her heat to reach the semi-finals. In her semi-final she ran 57.06, failing to reach the final. Parker won her first senior national title in June 1991, winning the
UK Championship title in 57.64. On 24 July, she finished fourth in the final at the
1991 Universiade in Sheffield, in 56.93. Three days later, she again finished second to Gowry Retchakan at the AAAs Championships, running a lifetime best of 56.15 secs to earn World Championship selection. At the
1991 World Championships in Tokyo, she was eliminated in the heats in a disappointing 57.81. She began the 1992 season by finishing third at the UK Championships behind Retchakan and Louise Fraser, running 56.99. She then narrowly missed Olympic selection by finishing fourth at the AAAs Championships, which incorporated the Olympic trials. With
Sally Gunnell (who won the sprint hurdles at the trials) already assured selection, there were two places available in the 400 m hurdles. The race was won by Gowry Retchakan in 55.04, with Australian Gail Luke second in 56.25. The final Olympic place went to Louise Fraser, as she edged out Parker 56.30 - 56.35. Parker was named as an Olympic reserve. Parker finished second at the 1993 UK Championships in 57.14, behind Gowry Retchakan. She then won the AAAs title with a time of 58.14, earning selection for her second World Championships. At the
1993 World Championships in Stuttgart, she ran 56.93 in her heat to reach the semi-finals, where she was eliminated running 56.68. She then finished second at the 1994 AAAs Championships, once again behind Retchakan, 57.14 - 57.31, to earn selection for the
1994 European Championships in Helsinki. At the Europeans, she was eliminated in the heats with 57.83. A few weeks later, she reached the final at the
Commonwealth Games in Victoria, finishing sixth in 56.72. ==Competition record==