44-year-old British athlete Douglas Waymark died after trying to swim across the English channel, reports the BBC.
The race was part of the competition on extreme triathlon Enduroman arch.
The swimmer felt badly about 12 miles from Dover.
A coast guard helicopter delivered the athlete to the hospital William Harvey in Ashford, where he died shortly thereafter.
Enduroman arch — competitions in extreme triathlon. The race starts in London and ends in Paris.