Despite his young age, Milosz is already a very successful athlete. He was the first Pole to qualify for the IM 70.3 World Championship in elite PRO category in 2016.
He also holds the Polish record at this distance: 3 hours, 45 minutes and 27 seconds. He represented Poland at the European Games in Baku in 2015. Milosz was also the Polish champion in the sprint in the U23 category, as well as a multiple medalist of the Polish Triathlon Championships at different distances.
In 2018 and start of 2019 Milosz had already very strong results in middle distance racing internationally and already qualified for 2019 Ironman 70.3 World Championship in Nice.