Lavreniuk was born in Zhytomyr. In February 2023, he won two silver medals at the OMEGA Youth Series Competition in men's skeleton event.[3]
He competed at the OMEGA Youth Series Competition, held in Innsbruck and Pyongyang in November 2023, where he received silver and bronze medals in men's skeleton event.[4][5] At this competition he qualified at the 2024 Winter Youth Olympics.[6]
At the 2024 IBSF World Junior Championships, held in Lillehammer, Norway, Yaroslav won a bronze medal in men's skeleton event.[7]
Then he represented Ukraine at the 2024 Winter Youth Olympics, held in Gangwon, South Korea and won a silver medal in men's skeleton event.[8] That is the second medal and a first silver medal in Ukrainian national team at this Winter Youth Olympics.[9] He was also a country's flagbearer with Ukrainian biathlete Valeriia Sheihas during the opening ceremony.[10]
In January 2025, at the next IBSF Junior World Championships in Saint Moritz he won a gold medal in men's skeleton and became a U20 world champion.[11] On 31 January, Lavreniuk won a bronze medal in men's skeleton at the European U20 Championships in Sigulda.[12][13]
