Mahringer earned silver medals in the FIS Alpine Skiing World Championships 1950 at Aspen (slalom and downhill), and in the giant slalom she finished fourth. She was a six time Austrian Champion (downhill 1948, 1951, 1952; slalom 1951; giant slalom 1951; Alpine Combined 1951). Mahringer was born in Linz. She wed fellow skier Ernst Spiess in 1954. Together they founded the Mayrhofen Ski School. In 1955, they opened "Riki’s Skikindergarten", the world's first children's ski school. Riki and Ernst are the parents of Uli Spiess and Nicola Spiess who became Alpine ski racers like their parents.