A 1932 graduate of the Central Institute of Physical Education in Warsaw, that same year Pławczyk became the European champion in the high jump with a height of 1.96m, having already been a three-time national record holder in the event. He won a bronze medal in the decathlon event at the 1934 European Athletics Championships in Turin, and placed sixth in the same event at the 1938 European Athletics Championships in Vienna. He was a national champion on numerous occasions in the 1930s. In 1938, he moved to France and joined the army in 1940. From 1943 through 1948 he worked as a sports instructor in Vichy, Paris, and Rome, later working as a salesman and teacher, before returning to Poland.