The International Triathlon Union (ITU) has released a document called "Beat the Heat" in a bid to prepare athletes for high temperatures.
It comes as part of the build-up to Tokyo 2020 where races are expected to take place in warm weather.
Organizers have already moved the start of the men's and women's events to 6.30am in the hope of cooler conditions.
However, the temperature was nearly 30 degrees by 6am at the Olympic test event in August, according to the Japan Times.
France's Cassandre Beaugrand was treated in hospital for heatstroke and the run section of the women's race was halved from 10 kilometers to five.
Fears over heat prompted a decision to move the Tokyo 2020 marathons to Sapporo, 800 kilometers to the north of the capital.
Triathlon, however, is remaining in the city with a course around Odaiba Marine Park.