Norway 's swimming federation did not give a cause of the cardiac arrest . American swimmer Swimmer dies suddenly at the age of 26 . Dale Oen was on at a training camp in Arizona , Arizona when he collapsed . Dale Oen was the world 100-meter breaststroke champion and Swimmer silver medalist .
American swimmer Swimmer dies suddenly at the age of 26 . Dale Oen was on at a training camp in Arizona , Arizona when he collapsed . Dale Oen was the world 100-meter breaststroke champion and Swimmer silver medalist .