PLEASE CORRECT: It's not only Russians, but also a Ukrainian, and Belorusian name. Maybe even in other slavic countries. It's correctly "O-LEGH". NOT "Ah-lek". Also it means -- SAINT.
Oleg Yuriyovych Vernyayev is a Ukrainian artistic gymnast. He is the 2016 Olympic parallel bars champion and individual all-around silver medalist. Vernyayev is also the 2015 European individual all-around champion and the 2014 World parallel bars champion.
https://pl.m.wikipedia.org/wiki/Oleg
https://pl.m.wiktionary.org/wiki/Oleg
https://en.m.wiktionary.org/wiki/Oleg#Polish
https://www.behindthename.com/name/oleg/top/poland
https://dane.gov.pl/pl/dataset/1667,lista-imion-wystepujacych-w-rejestrze-pesel-osoby-zyjace/resource/54115/table?page=1&per_page=20&q=Oleg&sort=