Basel resident Ernst Kolb made his first appearance at the Swiss Greco-Roman wrestling championships in 1940 at Lausanne, coming in second place in the middleweight class, behind reigning champion Ernest Gogel. After finishing second once again in 1942, Kolb won the national title in his weight class in 1948, which led to his selection to the Swiss Olympic wrestling team to compete later that year in London. Competing in the middleweight Greco-Roman event, he lost to Kaare Larsen of Norway in the third round.