Uladsimir Tschapelin ran his first race in the Junior European Cup at the beginning of the 2006/07 season. It was not until 2008 that he achieved results in the top ten for the first time. In 2007 he took part in his first Junior World Championships in Martell and reached 65th place in the sprint. A year later he was already competing in all races in Osrblie and was 35th in the individual, 39th in the sprint, 27th in the pursuit and eleventh with the Belarusian Season. Tschepelin had bigger successes at the Junior European Championships in Nové Město na Moravě . In the individual he reached rank 29, in the sprint he was 17th, 13th in the sprint and with the relay he missed a medal with Jauhen Abramenka , Ihar Tabola and Maksim Jelissejeu in fourth place by just one place. In the summer of 2008 he started at the Junior World Championships on roller skis and was 14th in the sprint in Haute-Maurienne , 13th in the pursuit and won the bronze medal in the mixed relay competition with Karina Sawosik, Vera Kalbianok and Wital Zwetau . In 2009 the Belarusian started for the third time in a Junior World Championship. In Canmore he finished 29th in the individual, 21st in the sprint, 16 in the pursuit and won the bronze medal with Sergej Ruzewitsch, Zwetau and Uladsimir Aljanischka with the relay. In the same line-up, he won the bronze medal with the Belarusian relay team at the European Junior Championships in Ufa shortly afterwards. He also won bronze in the sprint behind Tarjei Bø and Simon Schempp . In the pursuit he fell back to ninth place, in the individual Tschepelin was ninth. He also started again with the juniors at the 2009 Summer Biathlon World Championships in Oberhof . In the Crosslaf sprint he came in 16th place, in the roller ski competitions came sixth in the sprint, third in the pursuit behind Erik Lesser and Pawel Magasejew and a second place with Sowosik, Ala Talkach and Rutsewitsch in the mixed relay behind the Russian representation.
Tschepelin has started in the performance area since the 2009/10 season . He competed in his first race, a sprint, in Idre as part of the IBU Cup and finished there on 31st 2010. In 2010 he made his debut in the Biathlon World Cup in Antholz . In his first race, an individual, he finished 25th and immediately won his first World Cup points.