Starting his sporting career only in his late thirties at the 1968 Olympic Games in Grenoble, Krienbühl mostly skated at the back of the field. However, in 1974, he introduced the one-piece skin suit into speed skating. In spite of the fact that he improved his times dramatically, he was initially laughed at. However, when other skaters also showed improvement, the top skaters quickly switched to the suits as well. Krienbühl also introduced minor improvements for skates.
Krienbühls best athletic achievement was an 8th position at the 1976 Olympic 10000 m. He stopped speed skating internationally at age 48 the next season, though he continued to skate competitively until 1986.