Runge's biggest success was his gold medal at the 1936 Summer Olympics in Berlin. He also won three medals at the European Amateur Boxing Championships (silver in 1934 and 1937 and bronze in 1939). In addition to that, he is an eight-time German amateur champion (1935–1939, 1941–1943), as well as two-time runner-up to Hein ten Hoff in 1940 and 1944.