Stepanov started training in the high jump in 1950, aged 17, and by 1954 had a personal best at 1.98 m. In parallel, he competed in the long jump, and in 1956 won a national competition with a decent result of 7.43 m. He was selected for the 1956 Olympics, but was replaced due to a leg injury. He was the gold medallist at both the 1957 World University Games and the World Festival of Youth and Students.WORLD STUDENT GAMES (PRE-UNIVERSIADE). GBR Athletics. Retrieved on 2014-11-08.World Student Games (UIE). GBR Athletics. Retrieved on 2014-11-08. He twice competed at the European Athletics Championships, finishing fifth in 1954 and sixth in 1958.
