Tadeusz Śliwak divided his life into two phases. In the first, he was an athlete, the leading sprinter of the Second Polish Republic, and a Berlin Olympian. In the second, a pilot of a night fighter squadron and an interpreter.

He was born on 20 November 1908 in Buczacz, in present-day Ukraine. He completed his secondary school education in Stryj, and his sporting backbone was formed by the Sokol Gymnastic Association, first by the local branch, and then by the Lviv Sokol-Matrix, with which he was associated throughout the 1920s and the first half of the 1930s. There he began to specialise in the 400-metre run, a distance requiring speed and endurance.

In the mid-1930s, his name regularly appeared in tables and competition reports. He moves to Legia Warsaw, then to Syrena and Warszawianka. Regardless of his club colours, he is always the mainstay of the Polish one-lap relay. He is a five-time Polish record holder, and screws up his personal bests during the Olympic season of 1936: 10.8s in the 100m, 22.0 in the 200m and 49.6 in the 400m.

He becomes Polish vice-champion eight times: in the 100m, 200m and, above all, 400m. Seven times he puts on the jersey with the eagle in inter-state matches, recording a total of fifteen starts and two individual victories. He culminates at the Berlin Olympic Games. Sliwak runs in the 4×400m relay together with Kazimierz Kucharski, Klemens Biniakowski and Antoni Maszewski. The Poles are third in their preliminary run and drop out of the competition.

Three years later, the treadmill is replaced by war. After the 1939 campaign, he makes his way to Hungary, then reaches England via Italy and France. In the Polish Air Force he serves as a radio observer in the 307th Night Fighter Squadron, the famous "Lviv Puffers". He flies until 1944.

After the war, he does not return to Poland. First he ends up in England, where he tests radar apparatus, then in 1946 he moves to Argentina, but not as a sprinter or pilot, but as an interpreter. He is fluent in Spanish and English, so translating becomes a new profession. Professionally, he goes to Canada. In Toronto, he still trains at the Diesel Engine School, but eventually stays with languages: he works as a translator until his retirement.

He dies on 26 February 1991 in Winnipeg .