Chumak won a bronze medal at the 2005 European Championships in Zalaegerszeg after being defeated 13–15 in the semi-finals by Poland's Tomasz Motyka. Along with Dmytro Karyuchenko, Maksym Khvorost and Bohdan Nikishyn, he earned the bronze medal in the épée team event of the 2006 World Fencing Championships after beating Hungary in the bronze medal match.