In the 1990s, Aleksandersen started his coaching career in Norway with the Aukra VBK team, where he started competing in the Norwegian 1st League Division. In 2001, he went to the US for experience in the United States Professional Volleyball League and was successful with the Minnesota Chill when he won the league.[citation needed]
After Aleksandersen coached Arie Selinger for a few weeks in Japan, he landed at German Volleyball League club Schweriner SC. In 2006, he was a German Volleyball League and German Women's Volleyball Cup winner. In 2007, he came in second in Germany as the DVV Cup winner. After five years in Germany, Aleksandersen returned to Norway for family reasons, where he coached KFUM in 2009, and in 2010 with UiS Volley, he became the Norwegian champion, and then he looked for the Norwegian women's national team.[citation needed]
From January 2010, Aleksandersen was a trainer in Germany at Schweriner SC and was also the head coach of the Finland women's national volleyball team. In the 2010–11 season, he secured the German championship with Schweriner SC, then left the club to concentrate on his position as Finland women's national team coach.[1] From 2012 to 2017, he was a coach with the Polish first division teams Wrocław and then BKS Stal Bielsko-Biała.
Aleksandersen was a Norway national team coach again beginning in 2018, until the 2019–20 season, when he moved to train the Turkish club Nilüfer Belediyespor, and after one year he returned to Germany to take over Allianz MTV Stuttgart. The team finished in the second position in the 2021 season, the second season with Stuttgart.[2][3] The team finished the season as champions, and won the German Women's Volleyball Cup and reached the final of the CEV Cup in the same year.