At the 1952 Olympics in Helsinki Hietanen joined in double kayak along with Kurt Wires on. Over 10,000 meters won the two Finns with 0.4 seconds ahead of the defending champion Sweden Gunnar Åkerlund and Hans Wetterström. The next day drove Wires and Hietanen over 1000 meters at the same time with the Swedish world champions Lars Glasser and Ingemar Hedberg across the finish line, the Finns won gold after evaluation of the target photos.
Four years later, Hietanen appeared at the Olympic Games in Melbourne in 1956 with Simo Kuismanen over 10,000 meters of. With almost three minutes behind the two bronze occupied the seventh place.
Hietanen was later member of the board of the Finnish Canoe Federation.