Marguerite Ruygrok was born on June 3, 1947, in Amsterdam, the Netherlands. She migrated with her family to Australia at a young age.
She began swimming at an early age and showed considerable talent for the sport, particularly in breaststroke events.
Ruygrok first came to national attention when she won a silver medal in the 200m breaststroke event at the 1962 Australian National Championships. This success earned her a place on the Australian swimming team for the 1962 British Empire and Commonwealth Games held in Perth, where she won a bronze medal in the same event.
In 1964, Ruygrok represented Australia at the Summer Olympics held in Tokyo, Japan. She competed in two events, the 100m breaststroke and the 200m breaststroke, but did not progress past the heats in either event.
Despite this disappointment, Ruygrok continued to compete at a high level in swimming for several more years. She won several more medals at the Australian National Championships and represented Australia in international competitions, including the 1966 British Empire and Commonwealth Games in Kingston, Jamaica, where she won a bronze medal in the 200m breaststroke event.
After retiring from competitive swimming, Ruygrok continued to be involved in the sport as a coach and administrator. She was the assistant coach for the Australian swimming team at the 1984 Summer Olympics held in Los Angeles, USA, and also served as the head coach for the Western Australian Institute of Sport swimming program.
Overall, Marguerite Ruygrok’s contributions to Australian swimming have been significant, both as a successful competitor in her own right and as a coach and administrator who helped to develop and support the next generation of Australian swimmers.