His first international races were at the 2016 Junior World Championships in Cheile Grădiştei, Romania . In the individual competition he was initially 42nd in the sprint strong 7th with only one shooting error. In February, Štvrtecký started at the 2016 Winter Youth Olympic Games in Lillehammer . In his three individual starts and in the relay he was always among the top 20. In the IBU Junior Cup 2016/17 he was always able to achieve good results. At the home European championships in 2017 in Nové Město na Moravě he was 19th (sprint), 8th (pursuit) and 64th (individual). At the subsequent Junior World Championships 2017 in Brezno - Osrblie , Jakub Štvrtecký once again only managed to place in the top 20. Jakub Štvrtecký made his World Cup debut on March 15, 2018 in the sprint of the Oslo World Cup. With three shooting errors, he finally turned 80. Štvrtecký won his first medals at the 2018 Junior Summer Biathlon World Championships . First in the mixed relay with Petra Suchá , Tereza Voborníková , him and Vítězslav Hornig . The quartet won gold. Just one day later, he triumphed in the 10 km sprint. The competitions took place again in Nové Město na Moravě . At the beginning of the 2018/19 season, Štvrtecký started in the IBU Cup , but was called up to the Czech national team for the World Cup races in Hochfilzen and Nové Město na Moravě . He also started in the World Cup at the subsequent competitions in Oberhof and Ruhpolding. At the 2019 Junior World Championships , he finished tenth in the sprint and pursuit races, among other things. Štvrtecký's first world championship was the 2019 world championships in Östersund, where he was used in the sprint and finished 65th after three shooting errors.
With the start of the 2019/20 World Cup , Jakub Štvrtecký started regularly in the World Cup and was able to celebrate his best World Cup result so far at the third World Cup station in Annecy, France, with a 16th place. Two weeks earlier he was able to achieve World Cup points for the first time at the season opener in Östersund .
World Cup placements
The table shows all placements (depending on the year, including the Olympic Games and World Championships).
1st - 3rd Place: Number of podium placements
Top 10: Number of placements in the top ten (including podium)
Points ranks: Number of placements within the point ranks (including podium and top 10)
Starts: Number of races run in the respective discipline