Olympic athletes risk the hottest weather in more than a century at the 2020 Tokyo Games as high summer temperatures in the capital highlight concern about holding global sporting events in extreme conditions.

Tokyo is set to host its second Summer Olympics in July and August, the hottest months in the city, where temperatures soared to 38 degrees last month. FIFA, soccer’s global ruling body, will meet next month to discuss switching the 2022 World Cup to Qatar’s winter amid concerns the summer heat would be unsafe for players and fans.

A temperature of 38 degrees or higher during the men’s marathon at the Tokyo Olympics would make it the hottest in at least 120 years. The warmest marathon in the history of the Olympics took place in 1900 in Paris, when more than half the runners had to withdraw due to exhaustion as temperatures were estimated at between 35 and 39 degrees, according to the Journal of Sports Sciences.

“It is unwise to plan an event in such extreme conditions,” said George Havenith, a professor of environmental physiology and ergonomics at Britain’s Loughborough University who has visited Tokyo several times in the summer. “There also is an increased risk for the spectators.”

In addition, the higher humidity in Tokyo makes summer temperatures feel even hotter than in such climates such as Athens, where there’s less moisture in the air, according to Tadayuki Iwaya, a Tokyo-based meteorologist at Weather Caster Network.

The temperature would feel like 63 degrees should the mercury hit 38 degrees in combination with Tokyo’s average 71 percent humidity, according to the U.S. National Weather Service’s Heat Index calculator. By comparison, the average daily high of 33.2 degrees and 45.3 percent humidity in Athens when it held the marathon in August 2004 would feel like 35 degrees, according to the index.

When Tokyo staged the Olympic Games in 1964, it was October, when the mean daily high was 19.6 degrees, data from the Meteorological Agency show. Tokyo’s mean highs were 31.4 degrees in July and 33.2 last month.

Hisao Shuto, a spokesman for the Tokyo 2020 Bid Committee, said an organizing committee will be set up in February to hammer out the details of Tokyo’s event.

Japan proposed that the Olympic Games be held from July 24 to Aug. 9, 2020, according to its plan for the event. Istanbul suggested Aug. 7 to Aug. 23, and Madrid the same dates, according to an International Olympic Committee report on the rival bids.

The dates for the Tokyo Games were proposed to correspond with the international sports calendar, specifically between July 15 and Aug. 31, said Andrew Mitchell, media relations manager for the IOC.

“The health of the athletes is clearly a top priority for the IOC, but at this stage it is too early to comment on any specific measures, such as holding the marathon in the morning at Beijing 2008,” Mitchell said.

Other countries have held the Olympics at later dates. Sydney hosted the event from late September to early October in 2000, as did Seoul in 1988, while Mexico held the games in October 1968.

FIFA President Sepp Blatter faces opposition to rescheduling the 2022 World Cup from Europe’s biggest soccer leagues, clubs and broadcasting rights owner, which are all concerned changing the dates would disrupt national leagues and clash with other sporting events. FIFA may have “made a mistake” in awarding the World Cup to Qatar in the summer, Blatter told Inside World Football.

U.S. Soccer President Sunil Gulati said last week FIFA officials should have held more discussions about Qatar’s summer climate before the Middle Eastern country was awarded hosting rights in December 2010.

The combination of humidity and heat in Japan could be debilitating as athletes seek to compete at the highest level. More than a dozen people in the nation died of heatstroke and thousands were hospitalized last month when the mercury in Tokyo climbed to 38 degrees.

“The longer the event, typically the higher the risk of accumulation of heat in the body, with possible symptoms of heat exhaustion or even heatstroke in the worst case,” said Loughborough University’s Havenith. The 10-km race and the marathon would be among those posing the biggest risk, he said.

The Texas-based University Interscholastic League, created by the University of Texas to provide guidance to athletic teachers, has produced manuals with recommendations to coaches on how much exercise to do during summer months, including limits on how many hours and how frequently student athletes can practice.

“The maximum length of any single practice session is three hours,” said Kate Hector, a spokeswoman for UIL. “All of these rules were created to help prevent heat illness or heat-related injuries.”

At the Athens Olympics women’s marathon in 2004, eight of the 66 women who finished the course took more than three hours, according to Marathon Guide. Temperatures reached 35 degrees during the race.

“Running a marathon would be especially difficult,” Weather Caster’s Iwaya said. “Even regular exercise is difficult in that heat.”

At least six athletes died during a 2011 heat wave in the U.S. South, according to a report from ABC News.

Tokyo’s August high and humidity this year generated a heat index of 44 degrees, according to the U.S. National Weather Service, which designates that level as a “danger” zone for prolonged exposure or strenuous activity.

“Tokyo could try changing the times of events to cooler periods,” Iwaya said. “But it’s already 30 degrees Celsius in the morning.”

KEYWORDS 2020 Olympics