After good results in the junior division, Falk was nominated for a World Cup competition for the first time at the age of 18. In March 2007 she started in the sprint competition in her home Stockholm . However, as 49th, she clearly failed to qualify for the finals. At her first Junior World Championships in 2008 in Mals , she reached the semifinals in the sprint competition and finished eighth. Over the 5 km classic she was 27th and over the 10 km freestyle (mass start) 23rd. With the Swedish relay she won the silver medal behind Norway. In 2009 she reached the sprint final at the 2009 Junior World Championships in Le Praz-de-Lys-Sommand and just missed her first individual medal in fifth. After a 30th place over 5 kilometers freestyle, she was able to win the silver medal again with the Swedish team. At the beginning of the 2009/10 season , Falk was nominated for the sprint team of the Swedish World Cup team. On her first appearance in Kuusamo , Finland , she survived the qualification and narrowly missed the finals in her semifinals. With the seventh place she won world cup points for the first time in her career. A week later she started at the World Cup in Düsseldorf . There she reached the final run in her third World Cup start, where she surprisingly prevailed against Natalja Korosteljowa and Vesna Fabjan . After her first World Cup triumph, she was only beaten by the Italian team in the team sprint together with Ida Ingemarsdotter . In January 2010 she won the sprint in Otepää . At the 2010 Winter Olympics in Vancouver , she finished 29th in the sprint. At the end of the season she took 40th place in the World Cup finals in Falun and reached 20th place in the overall World Cup and fifth place in the Sprint World Cup. In the summer of 2010 she won the Rollerski World Cup sprint in Aure . In the 2010/11 season she came in World Cup sprints four times in the top ten, including second place in Otepää and reached tenth place in the sprint world cup at the end of the season. At the Nordic World Ski Championships 2011 in Oslo , she finished 11th in the sprint. In the 2011/12 season she was unable to continue her usual performance; in February, a bacterial infection was found to be the cause. In the following season she came in the points twice in the World Cup. Her best result was tenth place in the sprint in Québec .
In the 2013/14 season, Falk mainly started in the Scandinavian Cup . She got two victories and reached tenth place in the overall standings. In January 2014 she became the Swedish sprint champion. After 59th place at the Nordic Opening in Lillehammer at the beginning of the 2014/15 season, she came in the points in all World Cup participations. Her best placement was fifth in Davos . At the Nordic World Ski Championships in Falun in 2015 , she was disqualified in the sprint due to a false start and thus finished 94th. She finished the season in 31st place in the overall World Cup and eighth in the Sprint World Cup. In the 2015/16 season she took 17th place at the Nordic Opening in Ruka and 32nd place at the Ski Tour Canada . Her best placement of the season in the World Cup was fourth in the sprint in Stockholm . At the end of the season she came in 26th place in the overall World Cup and 11th in the Sprint World Cup. At the beginning of the 2016/17 season she finished 34th in the World Cup mini tour in Lillehammer. She was third in the sprint stage. She was also able to take third place in the sprint at the following World Cup in Davos. At the beginning of January 2017 she started in Lahti in the Scandinavian Cup. In doing so, she won the sprint and came second in the classic 10 km. This was followed by third place in the sprint at the World Cup in Toblach and second place with Ida Ingemarsdotter in the team sprint and third place with the relay in Ulricehamn . At the Nordic World Ski Championships 2017 in Lahti, she came in 15th place over 10 km classic and fourth in sprint. In March 2017 she achieved third place in the sprint in Drammen and third place in the sprint stage at the World Cup final in Québec , which she finished in 32nd place in the overall standings. She finished the season in 20th place in the overall World Cup and third in the Sprint World Cup. At the end of March 2017 she became Swedish champion in the team sprint together with Maria Nordström in Umeå . After finishing 26th in the Ruka Triple at the beginning of the 2017/18 season, she won the sprint in Dresden and also took second place in the team sprint with Stina Nilsson . In Lahti she was third in the sprint. At the 2018 Winter Olympics in Pyeongchang , she finished 21st in the 10 km freestyle and fifth in the sprint. At the World Cup finals in Falun, she came in 25th. She won the sprint stage and finished the season in 20th place in the overall World Cup and fourth in the Sprint World Cup.
In the 2018/19 season, Falk came in nine places in the points, 44th place in the overall World Cup and 20th place in the Sprint World Cup. At the World Cup in Lahti she finished third in the team sprint together with Evelina Settlin . In February 2019 she became Swedish sprint champion in Sundsvall and took 13th place in sprint at the season highlight, the Nordic World Ski Championships 2019 in Seefeld in Tyrol .
Sweden
Dusseldorf
Otepää
Meraaker
Lahti
