I.O.C. Moves Tokyo Games’ Marathon Site Because of Heat Concerns

Next year’s Olympic marathons in Japan will be moved from Tokyo to Sapporo because of expected extreme heat, the International Olympic Committee said Wednesday.

The walking races are also expected to be moved to Sapporo, which is 500 miles north of Tokyo. Temperatures there in late July and early August are expected to be about 10 to 12 degrees cooler than in Tokyo.

Heat has been the biggest concern for the Games. At its latitude, Tokyo is one of the hottest cities in the world during the summer months in which the Olympics will be held; over the past 10 Augusts, the average daily temperature was 82 degrees, with higher temperatures and humidity making for difficult conditions for sports competition. Hundreds of people die each summer from the extreme heat.

The 1964 Olympics in Tokyo were held in October because of that heat. But primarily because the I.O.C. wants to maximize its television audience and the money it can collect from media fees, especially in America, which pays the biggest broadcast rights fee, the 2020 Games were scheduled in the traditional summer window. Thomas Bach, the I.O.C. president, has said moving the games would create chaos in the international sport calendar and prevent top athletes from participating.

The Olympic committee has made several other moves to deal with the heat. The longer track races will be run in the evenings, when it is cooler. Morning rugby games will end before noon. There could be further changes, the committee said.

There are also plans for tents, water misters, fans and sun visors for spectators.

Before the decision to move the marathons, organizers were resurfacing the course with a material called Perfect Cool, which uses tiny ceramic beads to reflect heat. The races would also have started at dawn.

At a canoeing event in Tokyo in early September, organizers tried to cool spectators with shaved ice, but the experiment left fans soaked.

The men’s marathon typically comes on the last day of the Games and is considered a signature event, with the finish or medal ceremony often taking place in the Olympic Stadium. With the event taking place far to the north, its impact will be lessened, though the medal ceremony could potentially still take place before the closing ceremony, in accordance with tradition.

“Athletes’ health and well-being are always at the heart of our concerns,” Bach said Wednesday in a statement. “The new far-reaching proposals to move the marathon and racewalking events show how seriously we take such concerns.”