Estenstad, who competed for the Idrettslaget Leik from Hølonda, won fourth place at the Holmenkollen Ski Festival over 50 km in 1949 and 1950 . At the Nordic World Ski Championships in Lake Placid in 1950 , he finished 16th over 18 km and seventh over 50 km. The following year he was third at the Holmenkollen Ski Festival over 50 km. At the Olympic Winter Games in Oslo in 1952 , he won the bronze medal over 50 km and the silver medal with the relay. He came 11th in the 18 km run. In the same year he won the 50 km run at the Holmenkollen Ski Festival and received the Holmenkollen Medal for it the following year . At the Norwegian championships he won five times over 50 km (1948, 1949, 1952-1954) and once over 30 km (1950) and with the relay of IL Leik (1954). In addition, in 1953 he took second place over 30 km.