Christchurch-based French triathlete Laurent Vidal has suffered a heart attack while training in France.
Vidal felt pain in his chest while training at a pool in Sete, in the south of France, and went into cardiac arrest, French media reports say.
The 30-year-old was revived by firefighters and transported by helicopter to a hospital in nearby Montpellier.
Vidal is the fiance of New Zealand's top female triathlete, Andrea Hewitt, is based in Hewitt's hometown of Christchurch and raced in the New Plymouth ITU World Cup race last month.
Hewitt is travelling to France to be with him but tweeted: ''Thank you everyone for your kind words for Laurent. Your support means so much. Shocked and so worried!''
Vidal, who was fifth at the 2012 London Olympics, was expected to be in an induced coma for about 48 hours, reports said.
What do you think of the sentence handed down to former Olympic and Paralympic sprinter Oscar Pistorius?Related story: (See story)