Four friends in Sweden get drunk, and a new competitive sport is born.

The friends made a fun bet during a night of revelry, challenging each other to race from island to island, swimming and running and stopping at restaurants along the way. The last team to finish had to drink and pay for what the team ahead of it had ordered for them.

In 2006, a version of the race — minus the eating and drinking aspect — went commercial in Sweden, attracting 11 teams. Then it picked up steam. Four years ago the swimrun phenomenon spread to the United States.

Fit City writer Pam LeBlanc recently competed in SwimRun Georgia in Atlanta. Read more about her experience in a story on our premium website.