In her youth competitive swimmer Ruth Kerr broke five Canadian records at one swim meet at the Kennedy Collegiate in Windsor, Ontario. Kerr also swam open-water races where she came second in the inaugural Canadian National Exhibition Marathon Swim. She was soon identified as one of the best swimmers in the country and was selected to represent Canada at the 1932 Los Angeles Olympics. She was still only 16-years-old when she swam at the Games, making her the youngest member of the Canadian Olympic team. Individually she swam in the 100 metres backstroke and the 400 metres freestyle, in addition to finishing fourth in the 4 × 100 metres freestyle relay. Kerr was posthumously inducted into the Essex Sports Hall of Fame in 1987 and the Ontario Aquatic Hall of Fame in 2013. Her brother Gordon swam for Canada at the 1936 Berlin Olympics.