In 1955, Chromik won the 5.000 metres, ahead of Sándor Iharos, József Kovács, Emil Zátopek, and Zdzisław Krzyszkowiak, at the International Youth Festival in Warsaw. In 1955 and 1958, he won the 3000m in the Kusocinski Memorial in Warsaw.
In 1955, Chromik won the 5000 meters race at the International Youth Festival in Warsaw, defeating Sándor Iharos, József Kovács, Emil Zátopek, and Zdzisław Krzyszkowiak. He also won the 3000m event at the Kusocinski Memorial in Warsaw in both 1955 and 1958.