Whitewater slalom singles appeared for the first time at the Olympics at the 1972 München Olympics, where canoe slalom events were held on the canoe slalom course of Augsburg (and for the last time until 1992). West Germany’s Reinhold Kauder was the reigning C-1 World Champion, but East German Reinhard Eiben, however, was in first after run one, with Kauder in second and only 0.39 points behind, and another East German, Jochen Förster in third. Eiben recorded an even better score in the second run to earn a well-deserved gold medal, while Kauder failed to improve upon his point total and was forced to settle for silver. Eiben claimed the World Championships in 1973. He also was World Team Champion in 1977, and earned silvers in 1973 and 1975.
Eiben was East German champion in 1972 and 1975, and with SC DHfK Leipzig also won team titles in 1972, 1973, 1975, and 1976. He trained as an industrial blacksmith and was employed by the region Leipzig until reunification. He then moved to Schleswig Holstein in the former West Germany where he ran a petrol station in Wankendorf. He was inducted into the German Canoe Slalom Hall of Fame.