Aasen Ouren, who starts for Øvrebø IL , ran his first race in the Continental Cup in Nybygda in January 2000 . There he finished 56th over 10 km classic. He made his debut in the World Cup in March 2000 in Oslo , which he finished in 45th place in the sprint. In November 2003 he got his first world cup points in Beitostølen with the 25th place over 15 km freestyle. In the 2004/05 season he was seventh and two in Veldre tenth overall in the Scandinavian Cup . In the following season he came in the points in all World Cup participations. He achieved five top ten placements and achieved his best individual result in the World Cup with fifth place in the 50 km mass start race in Oslo. He finished the season in 22nd place in the overall World Cup and 13th in the Distance World Cup. In the 2007/08 season he finished fifth with two second places and in the 2008/09 season with two third, one second and one first place, the second place in the overall ranking of the Scandinavian Cup. In January 2010 he won his second Scandinavian Cup win over 20 km freestyle in Åsarna . He ran his last World Cup race so far in November 2010 in Gällivare , which he finished in 13th place with the relay. He has been participating in the Worldloppet series races since 2011 . His best placement was fourth place at the Vasaloppet China in January 2016.