Miętus, who starts for AZS Zakopane , began his international career at the age of 14 in the lower-class FIS Cup . In 2008 he started in his home town Zakopane for the first time in the Ski Jumping Continental Cup .
At the Junior World Championships in 2009 in Štrbské Pleso , he won bronze with the team in the team competition and took 20th place in the individual competition. His first appearance in the Summer Grand Prix took place on October 3rd, not only setting up his personal best distance in Klingenthal with 137.5 m, but also winning his first Grand Prix points in 28th place. A week later he was at the Polish Championships in Zakopane behind Adam Małysz and Łukasz Rutkowski third in the competition on the large hill.
On 20 December 2009 he was in Estonian Otepää on Tehvandi ski jump win his first Continental Cup jumping. On January 22nd, 2010 he qualified for a World Cup for the first time in his hometown Zakopane . With rank 48 it was not enough for the jump into the points. He achieved his best result on February 6, 2010 at the World Cup competition in Willingen , where he finished in 20th place.
In July 2016, Miętus announced the end of his career.
Poland
Otepää