Education
During the 2000 Summer Olympics in Sydney, he finished in eighth position in the mistral class.
During the 2000 Summer Olympics in Sydney, he finished in eighth position in the mistral class.
The gap between Miarczyński and fourth placed Joeri van Dijk was 24 points.
In 2001 he won a silver medal at the Junior and Senior World Championships. He became World Champion in 2003 and finished in fifth position during the 2004 Summer Olympics. In the Olympic season, he also became European Champion and a World Champion runner-up. Miarczyński won the bronze medal at the 2006 RS:X World Championships. He finished only one point behind world champion Casper Bouman and Tom Ashley who had as much points as Bouman. At the 2012 Summer Olympics, he won the bronze medal in the RS:X class.