At the 1912 Summer Olympics in Stockholm, Sweden, Moore won a gold medal as a member of the first-place British women's team in the 4×100-metre freestyle relay, together with teammates Jennie Fletcher, Annie Speirs and Irene Steer. The British women set a new world record in the event of 5:52.8, beating the German and Austrian women's relay teams by a wide margin. Swedish King Gustav V presented Moore and her teammates with their gold medals and Olympic laurels.