Canadian runner Daundre Barnaby died after drowning during a team training camp in St Kitts on Friday.
Barnaby, who represented Canada at the London Olympics, drowned after a strong current took him out during down time he was enjoying with team-mates.
The 24-year-old's team-mates tried to save him before he was found four-and-a-half hours later by local search and rescue.
"It is with heavy hearts that Athletics Canada announces the passing of national team athlete Daundre Barnaby of Brampton, Ontario, during the East Hub training camp in St Kitts," an Athletics Canada statement read.
Athletics Canada chief executive Rob Guy said: "This is such a sad and profound loss, Daundre was an outstanding athlete and an even better young man.
"On behalf of Athletics Canada I offer my sincere sympathies and condolences to Daundre's family and team-mates.
"Athletics Canada will do whatever is necessary to support the athletics family through this tragedy."
Born in Jamaica, Barnaby became a Canadian citizen in 2012 and the specialist 400-metre runner represented the nation in London.
Barnaby also competed at the 2014 Commonwealth Games.