In 1995, Samuelsson accidentally broke the arm of Australian wrestler Nathan Jones during heats of the World’s Strongest Man contest in Nassau, Bahamas. The injury occurred because Jones employed the novice technique of side twisting. The action combined with Samuelsson’s own body strength resulted in a snapped humerus.

In 2001, Samuelsson became the overall champion of the Strongman Super Series. After competing in the IFSA Strongman World Championship in 2005, he returned to compete in the 2006 World’s Strongest Man but failed to make it past the qualifying rounds due to a back injury. A year later, Samuelsson reached the 2007 finals, eventually finishing in 5th place. However, after failing to make the finals in the 2008 World’s Strongest Man contest, Samuelsson announced his retirement from competition after 14 years competing in the sport. He achieved a 31 podium finish making him one of the all-time most successful strongman competitors. Samuelsson also remains one of only five men to have successfully closed the No. 4 Captains of Crush hand-gripper under official conditions.

In 2009 Samuelsson won the Swedish version of the television series Dancing with the Stars, beating songwriter Laila Bagge in the final.

Samuelsson is also an automobile racing enthusiast. In 2010 he competed in Rally Sweden, part of the World Rally Championship, finishing in 35th position out of 55.

Samuelsson plays Gunnar Nyberg, a detective in the 2011 Swedish crime thriller series Arne Dahl. It has also been aired in Germany and UK. The series are now available on Amazon Prime.