Jungwirth started training seriously in 1949.[1] By 1951, he was already a quality runner, running the 1500 metres in 3:48.8;[1] Track and Field News ranked him No. 8 in the world that year.[2] In 1952, he won the Czechoslovak championship at both 800 and 1500 metres and was selected to run the latter distance at the Olympics in Helsinki,[1] where he survived the heats but went out in the semi-finals.[3] Late in October 1952, he set a new world record at 1000 metres in Stará Boleslav, running 2:21.2 to better Olle Åberg's time by 0.1 seconds. This record was broken less than ten months later by the United States' Mal Whitfield.[4]
Jungwirth continued improving and won his only international medal at the 1954 European Championships in Bern, where he was third behind Roger Bannister and Gunnar Nielsen with a time of 3:45.4.[1][5] At the 1956 Olympics in Melbourne he finished 6th in 3:42.6.[1][3][5]
On 12 July 1957 - again in Stará Boleslav - Jungwirth ran 1500 metres in 3:38.1, breaking the world record of 3:40.2 set just the previous day by Finland's Olavi Salsola and Olavi Salonen.[4][6] A week later in London, he was the first Czechoslovak to run a four-minute mile;[7] however, his time of 3:59.1 was only good enough for third place[5] while the winner, Derek Ibbotson, ran a new world record 3:57.2.[4][7]
Jungwirth suffered from health problems in 1958[1] and was 8th at the European Championships, even though his time of 3:44.4 was a second faster than his bronze medal performance in 1954.[5] He lost his world record on 28 August 1958, when Australia's Herb Elliott ran 3:36.0 in Gothenburg;[4] Jungwirth himself was second in that race in 3:39.0.[1] Jungwirth's health problems continued in 1959 and 1960 and he was unable to take part in the 1960 Summer Olympics in Rome. He retired from athletics as a result.[1]
Track and Field News ranked Jungwirth in the world's top 10 at 1500 metres seven times between 1951 and 1959, with a highest ranking of No. 3 in 1957. Jungwirth also made the top 10 at 800 metres in 1952 and 1953.[2]
Czechoslovakia
