Kiernan was born in
Listowel,
County Kerry. He represented his native country at the
1984 Summer Olympics in
Los Angeles, California, where he finished in ninth place in the
men's marathon. Kiernan twice won the
Dublin Marathon, in 1982 and 1992, as well as in
Belfast in 1990 and in 1992. He also won the national cross country title in 1984. A former
Irish record holder over
3000 metres, Kiernan was a sub-
four-minute mile runner being the seventh Irish runner to break that barrier in June 1976. Kiernan represented Ireland 17 times between 1975 and 1993, competing seven times in world cross-country championships, and won five Irish titles, from the 1,500m to the marathon, and also national inter-club and inter-county cross-country titles. His running club in Dublin was
Clonliffe Harriers. Kiernan coached many athletes including
Ciara Mageean and trained regularly in the UCD campus. He was a regular part of
RTÉ's athletics television coverage. ==Achievements==