Gould grew up around the water in Fiji and Australia. At age 15 she competed in the 1972 Olympic Games in Munich, West Germany; swimming 11 races in eight days, she captured gold medals in the 200-metre individual medley, 200-metre freestyle, and 400-metre freestyle, all in world record times. She also won a silver in the 800-metre freestyle and a bronze in the 100-metre freestyle, dominating the women's swimming field. In 1973 her time in the 1,500-metre freestyle was clocked at 16 min 56.9 sec, setting a world record and making her the first woman to break the 17-minute mark in that event.

Gould's stroke—two shallow kicks for each cycle of the arms—had long been utilized by distance swimmers but never before by a sprinter. Though named the "Australian of the Year" in 1972, Gould ended her three-year career and retired from competition at age 16. Dropping out of the public eye, she resurfaced in the 1990s as a swimming mentor and competitor at the masters level. Her autobiography, Tumble Turns, was published in 1999.