When he was 17-years-old Jørgen Frantzen served as the coxswain for the Danish coxed pairs team at the 1952 Helsinki Olympics. Along with Svend Pedersen and Poul Svendsen, Frantzen helped the Danish crew to finish second in their heat to advance to the semi-finals. They then faced stiff competition from the German and French teams, resulting in Denmark finishing in third place, but having a second chance in the repêchage round. After beating Poland in their heat they advanced to the final where they once again came up against France and Germany, who won gold and silver, respectively. Frantzen, Pedersen, and Svendsen finished third to win bronze. On their return home to the town of Frederiksværk the crew were met by a crowd of more than 2,000 people to celebrate their success.