Keijo Koivumäki competed most of his career with his older brother Eero and together they became the top Finnish double scullers at the start of 1950s. But their only international appearance at the 1952 Olympics, held at their homeground in Helsinki was not so successful, as they were last at both their round one heat and round one repêchage and did not advance to the semi-finals. Eero and Keijo Koivumäki were Finnish double sculls champions 1952-54, coxless pairs champions in 1950 and coxed eights champions in 1947-48. After finishing his sporting career, Keijo Koivumäki became a well known Finnish sports and government official. He was the general secretary of the Finnish Rowing Federation from 1955-57 and 1960-66 and was treasurer of the Finnish Rowing Federation from 1948-51 and again beginning in 2001. He was also chief editor of Airo Lehti, a monthly Finnish rowing magazine, in 1960. From 1969-71 and 1979-81 Koivumäki was general secretary of Nordic Post and Telegraph Agency and from 1966-89 was general secretary of Finnish Post and Telegraph Agency. From 1975-80 he was a member of the board of directors of Finnish Ministries and Central Agencies Sport’s Association. He has received the Finnish Rowing Federation Golden Badge in 1980, the Finnish Sports silver Cross of Merit in 1981, the Order of the Lion of Finland Cross of Merit in 1983, and the Finnish Post and Telegraph Agency Golden Badge in 1986.