|Representing Russia and Kazakhstan|
|2001 Fukuoka||25 km open water|
|2003 Barcelona||25 km open water|
|2007 Melbourne||25 km open water|
|2002 Berlin||25 km open water|
In 2007 he narrowly missed the world record for the fastest swim across the English Channel when he was beaten by Petar Stoychev. His time of 7 h 06 min remains one of the fastest swims ever recorded, but was not enough to beat Stoychev's 6 h 57 min set on the same day (24 August 2007).
Earlier in the year (25 March 2007), Kudinov beat Stoychev in the 25 km at the Open Water World Championships, a race which he won in a time of 5 h 16 min 45 s, with Stoychev coming in 6th with a time of 5 h 22 min 55 s.