Trask had at the Olympic Games in 1980 can not participate because of the Olympic boycott. The World Rowing Championships 1983 in Duisburg, the New Zealand coxed four in the cast Leslie O'Connell, Keith Trask, Gregory Johnston, Conrad Robertson and helmsman Brett Hollister won the title before the boats from the GDR and the USSR. At the Olympic Games in 1984 O'Connell, Robertson and Trask came along with Shane O'Brien as a coxless four. In the absence of the boats from the Eastern Bloc, the New Zealander won before the U.S. boat and the Danes. The World Rowing Championships 1985 in Belgium Ross Tong sat for Robertson in the four who finished fourth behind the boats from Germany, the USSR and the GDR.
The 1.90 m wide Trask rowed for the North Shore Rowing Club in Auckland.