Bergdølmo began his senior career at Lillestrøm in 1991, before transferring to Rosenborg for a fee of 700,000 kr ahead of the 1997 season.
Upon retiring at the end of the 2008 season, Bergdølmo had won the League Championship seven times with three clubs, and earned 63 caps for the Norway national football team.
Bergdølmo started his playing career in Skjetten, and went from there to Lillestrøm in 1991, where he gradually became known as one of the best defenders in Norway.
Bergdølmo won four league titles with Rosenborg, and was ever-present for Norway at the Euro 2000.
He retired at the end of the 2008 season, but would continue playing sporadically for Sørum on the eighth tier of Norwegian football.