Born in Kiel, Nürnberg won four times the German Championship in the Lightweight class (1937, 1940, 1941, 1942) and took thrice the 2nd place (1939, 1943, 1944), won the International Tournament at Berlin 1937, won the International Meeting at Berlin 1938, and won twice the gold medal at the 1937 European Amateur Boxing Championships in Milan and the 1939 European Amateur Boxing Championships in Dublin.