Russian archer Svetlana Gomboeva fainted in the heat and had to be taken out of the arena on a stretcher during a qualifying Olympic round on Friday.
Svetlana Gomboeva, 23, collapsed as she checked her final scores and needed help from staff and team-mates who put bags of ice on her head to cool her down.
The Russian quickly regained consciousness after collapsing but needed to be stretchered out of the arena by medical officers.
Archery - Tokyo 2020 - Olympic Highlights
The heatwave in Tokyo forced coaches and staff to huddle under trees for shade.
Gomboeva’s coach Stanislav Popov told reporters: "We hope that she will be okay.
"It turns out that she couldn’t stand a whole day out in the heat. This is the first time I remember this happening.
“In Vladivostok, where we were training before this, the weather was similar. But humidity played a role here."
Gomboeva’s team-mate Ksenia Perova said she was recovering well and would be able to resume competition.
She said: "Everything is fine with Sveta now.”
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With temperatures peaking around 33 degrees Celsius (91 Fahrenheit) in the archery dome on the first day of competition, athletes had challenges with hydration and staying cool.
South Korea's Kang Chaeyoung, who came third in the individual ranking rounds, said she had not experienced anything like Tokyo's heatwave conditions in other recent events.
Australia's Alice Ingley had some advice for her fellow competitors on how to beat the heat.
"Cooling vest, slushies, fans, umbrellas, just all that, just try to keep out of the heat as much as possible," she told Reuters.
"And drink water as much as possible."
The archery competition is taking place until July 31st.
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