Lysdahl competed in her first FIS races in her home country from December 2011 . After several results among the top 10, she achieved her first success at this level in a giant slalom in December 2013 . In preparation for the 2014/15 season, she competed in a number of races in the Australian New Zealand Cup and achieved two placements among the top ten. On December 1, 2014, she made her debut in the European Cup at the Hemsedal slalom, finishing in 28th place where she immediately scored the first points in this racing series. Later in the winter she started in Hafjell at the Junior World Championships , where she achieved twelfth place in the downhill as her best result . At the end of the season at the Norwegian Championships she won bronze in the downhill behind Mina Fürst Holtmann and Maria Therese Tviberg .
In the following season, Lysdahl showed improvements, especially in downhill and giant slalom. In January 2016, she finished sixth in the giant slalom in Zinal , her first top ten finish in the European Cup, which she followed a month later with third place in the downhill from Davos with her first podium. At the Junior World Championships held in Sochi that same year , she won bronze with the team and was also sixth in slalom and eighth in downhill. On March 11, 2016, she celebrated her first victory in the European Cup at the same time as Christina Ager on the downhill run from Saalbach-Hinterglemm . The winter of 2016/17 began successfully for Lysdahl: she won the European Cup giant slalom in Trysil and achieved three more podium places in this racing series by mid-December.
On December 27, 2016, Lysdahl was used for the first time in the World Cup at the giant slalom on Semmering , but missed the qualification for the second round. A day later she won the first World Cup points in another giant slalom in the same place as 17th. At the 2017 World Championships in St. Moritz , she competed in four disciplines and achieved 17th place in the combination as the best result. At the end of the winter, she became the Norwegian combined champion in Narvik . She started the 2017/18 World Cup season with eighth place in Sölden . At the 2018 Winter Olympics in Pyeongchang , she won the bronze medal in the team competition.