In addition to skiing, Holmlund also showed talent as a football player in her youth . She played for several years for Sundsvalls DFF in Division 1, Sweden's second highest league. In 2009 she decided to devote herself entirely to ski cross. She made her debut in the Freestyle World Cup on January 10, 2009 with 28th place in Les Contamines . Two months later, she improved to fifth place in Hasliberg .
Holmlund's final breakthrough came in the 2009/10 season . She celebrated her first World Cup victory on December 21, 2009 in San Candido and was able to repeat this success the following day. Before the 2010 Winter Olympics , she was one of the favorites. At the Olympic race in Cypress Mountain she reached the 6th place. At the end of the season she won two more World Cups. At the beginning of the 2010/11 season , Holmlund achieved two World Cup victories and a third place, which made her one of the favorites for the 2011 World Cup : In Deer Valley , she won the bronze medal. After the World Championships, Holmlund continued her winning streak with three more successes and won the ski cross discipline for the first time.
During the entire 2011/12 season, Holmlund had to take a break due to injury. In the following winter of 2012/13 , a second place was her best result, followed by two third places. She achieved another third place in the 2013/14 World Cup season . She won the bronze medal at the 2014 Winter Olympics in Sochi . In the 2014/15 season , Holmlund won three World Cup races and made it onto the podium four times. As a result, she secured victory in the discipline classification for the second time, while finishing second in the overall classification with a narrow gap. In contrast, the 2015 World Championships on Kreischberg were unsuccessful. In the 2015/16 season she successfully defended her title in the Skicross World Cup. She won five races, came second four times and third once; the worst result was a fifth place.
On December 19, 2016, Holmlund had a hard fall while training on the San Candido track. She suffered cerebral haemorrhage, had an operation in Bolzano and was in a coma until May 2017 . A return to skiing was ruled out at the time. She was able to leave the hospital and has been cared for by her father at home in Sundsvall ever since. At the end of October 2017 she appeared in public for the first time while sitting in a wheelchair.