Martin was born on 29 April 1967 in Sydney, as the fourth of six children. Her older brothers Brett and Rodney also went on to be top professional players. Her parents, who had built the Engadine Squash Centre below their family home, introduced her to the game when she was three years old. She would often play squash with her family after school, and at the age of eight, she came second in the state under-13s championship. She moved with her family to Brisbane In 1980, and attended Everton Park State High School.