Swimrun: How drunken bet became worldwide sport
Swimruns started in Sweden in 2006 after a drunken bet between friends to run and swim between islands.
Since then it's become a serious sport, with more than 500 events around the world.
The latest was held in south Devon where the Vivobarefoot competition saw about 100 entrants compete across 10km and 25km routes.
We followed author and podcaster Dr Rangan Chatterjee taking his first steps in the sport.
Video Journalist: Jonathan Morris