The Pole, who specializes in sprint competitions, began his professional career in 1994 and ten years later won his only World Cup in the free technique sprint in Trondheim . In addition, he was placed in the top ten in the sprint ten more times, including a third place in 2005 in Reit im Winkl . In addition, he managed a single-digit placement in a sprint during the Tour de Ski 2006/07 with fourth place. In endurance races, he was only able to place himself in the top 10 in the World Cup at the 15 km classic race in Beitostølen in 2005.
Since 1995 Krężelok took part in the Nordic World Ski Championships for Poland. His best results here were a seventh place in the sprint in Oberstdorf 2005 as well as a fifth place in the team sprint with Maciej Kreczmer and a tenth place in the sprint in Sapporo 2007.
He also started at the Olympic Winter Games in Nagano, Salt Lake City and Turin. Here he achieved a seventh place in the team sprint (also with Kreczmer) in 2006 and a ninth place in the sprint in 2002.