Lopez began gymnastics at the age of seven in 1984. By 1987, she was competing in international meets as a junior, including the 1987 Puerto Rico Cup, where she won a bronze medal on the floor exercise. In 1990, Lopez nearly swept the Mexican national championships, placing second in the all-around and winning the titles on the balance beam, floor exercise and vault. She represented Mexico at the 1991 World Artistic Gymnastics Championships, but placed well out of the medals on every event.