2017—2020: European Championship medals and first World Cup victory Ida Lien made her international debut at the
2017 Junior European Championships in
Nové Město na Moravě,
Czech Republic. However, those races remained her only appearances at the junior level. Two years later, she participated in her next international competitions at the
2019 European Championships in
Minsk. There, she stood out with a ninth place in the sprint and seventh in the pursuit, securing two Top-10 finishes right away. For the remainder of the
2018/19 season, she competed in the
IBU Cup, achieving another Top-10 result with a seventh place in the sprint in Otepää. In the following season, Lien started the IBU Cup from the beginning. After two more Top-10 finishes in the sprint races in
Sjusjøen and
Osrblie, she achieved her first podium finish in the mixed relay in Osrblie, teaming up with Sindre Pettersen, Håvard Bogetveit, and
Emilie Kalkenberg to take third place. Following three consecutive ninth-place finishes, she claimed her first IBU Cup victory in the Mass Start 60 in
Martell. At the
2020 European Championships, Lien won a bronze medal in the mixed relay alongside Åsne Skrede,
Sivert Bakken, and
Aleksander Fjeld Andersen. She also earned a silver medal in the sprint, finishing behind
Elisabeth Högberg after a flawless shooting performance. She capped off the competition with a tenth-place finish in the pursuit. On 5 March 2020, she competed in her first World Cup race in Nové Město na Moravě. In the sprint, four shooting misses and a time deficit of over three minutes kept her well out of the points and the pursuit qualification. Two days later, she substituted for ill world champions
Synnøve Solemdal and
Marte Olsbu Røiseland in the relay race. Partnering with
Karoline Offigstad Knotten,
Ingrid Landmark Tandrevold, and
Tiril Eckhoff, she achieved a victory on her debut.
2020—2022: Breakthrough season and continued success At the start of the
2020/21 season, which Ida Lien competed entirely in the World Cup, she scored her first World Cup points by finishing 30th in the individual race in
Kontiolahti. Shortly after, she came close to the Top 10 with a 12th place in the sprint in
Hochfilzen. Lien had a particularly successful debut at the
World Championships. She achieved Top-17 finishes in the individual, sprint, and pursuit races, qualifying for her first mass start. Running third in the women’s relay, she kept the team in the lead, ultimately securing the gold medal alongside Ingrid Landmark Tandrevold, Tiril Eckhoff, and Marte Olsbu Røiseland. Throughout the season, Lien consistently earned World Cup points and, in March 2021, achieved her first Top-10 individual result with a ninth-place finish in the
Östersund sprint. She ended the season ranked 29th in the overall standings, the fifth-best Norwegian athlete. In the
2021/22 season, Lien's performances peaked in December, highlighted by a fourth-place finish in the Hochfilzen sprint, where she narrowly missed her first podium by just over two seconds. After a series of average results, she impressed in
Antholz, bringing the Norwegian women’s relay team from a significant deficit to the lead with flawless standing shooting, contributing to their eventual victory. Lien also participated in the
2022 Beijing Olympics but struggled in individual races, finishing outside the Top 30. In the relay, she placed fourth after Tiril Eckhoff incurred two penalty loops. The season concluded with another relay win in Kontiolahti and Lien ranking 36th overall in the World Cup standings.
2023—2024: Inconsistent performances and two European Championship victories in
Oberhof During the
2022/23 winter season, Lien achieved just one result in the Top Ten. Due to several shooting errors, she missed points in several races but remained part of the national team. At the
World Championships in
Oberhof, her best result was 17th place in the individual event, while the relay team finished sixth after a total of four penalty loops by Lien and Ingrid Landmark Tandrevold. At the end of the season, she celebrated her fifth victory with the women’s relay in Östersund. Together with Frida Dokken and Tuva Aas Stræte, she also won the Norwegian national title in the relay event. In preparation for the following season, Lien struggled with back issues throughout the second half of the year and missed almost the entire month of December. She returned to competition with the IBU Cup races in
Sjusjøen, where she immediately achieved two podium finishes. After more strong results in
Ridnaun, Lien made her World Cup comeback in Antholz, where she impressed with a strong performance and a ninth-place finish in the shortened individual race. She then competed at the
2024 European Championships in Osrblie, where she became the European champion in both the sprint and the mixed relay, thanks to flawless shooting in both events. Despite a significant improvement in her back pain during the summer period, she, like the other members of the elite team, arrives in a relative poor form for the selection races in Sjusjøen in mid-November. Far from her usual performance on skis and too imprecise at the shooting range, she finishes 38th in the sprint and 14th in the mass start, and sees
Maren Kirkeeide,
Emilie Kalkenberg, and
Gro Randby chosen to start the season in the
World Cup. However, just fifteen days later, she manages to achieve a promising sprint-pursuit double victory in the IBU Cup at the first stage in
Idre Fjäll. ==Biathlon results==