Muffetangen made his debut on the
Norwegian national team in 1989, and played 106 matches for the national team between 1989 and 1996. He participated at the
1993 World Men's Handball Championship. In 1999 he won the Norwegian championship and cup double with
Sandefjord TIF. He won the
DHB-Pokal in 2001 with
VfL Bad Schwartau. He was in 1989, 1992 and 1993 the top scorer in the Norwegian top division. In 1989 he was named player of the year in the division. He retired in 2004. Muffetangen was awarded the
Håndballstatuetten trophy from the
Norwegian Handball Federation in 2013. ==Personal life==