[2] Sturla Holm Lægreid grew up in the municipality of Bærum near Oslo as the second of three children (with an older brother and a younger sister) in a sports-oriented family.

[4] During this time, he participated in the 2015 European Youth Olympic Winter Festival in Bürserberg, Vorarlberg, where he won silver in the pursuit behind Sebastian Samuelsson and gold in the mixed relay alongside Mathea Tofte, Karoline Erdal, and Aleksander Fjeld Andersen.

However, upon returning to Norwegian Cup events at the end of 2019, he faced significant difficulties at the shooting range and subsequently began mental training and meditation.

Toward the season's end, Lægreid made his first four World Cup appearances in Nové Město na Moravě and Kontiolahti, hitting 59 of 60 shots[9] and finishing between tenth and fifteenth place in all four races.

At the first World Cup of the new season in Kontiolahti, he surprisingly won the season-opening 20 km individual race with clean shooting during just his fifth start in the series, taking the yellow bib as overall leader.

The relay, which also included Johannes Thingnes Bø and Vetle Sjåstad Christiansen, ultimately won the race, earning Lægreid an Olympic gold medal.

[14] At the start of the 2023–24 Biathlon World Cup season, Lægreid struggled for form during the Östersund races and repeatedly missed the top ten.

During the Lenzerheide World Cup in December 2023, Lægreid accidentally fired a shot in the team accommodation during dry-fire practice, having mistakenly loaded a full magazine instead of an empty one.