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Health Risks at the Rio Olympics, by a Doctor Who Was There

Bert R. Mandelbaum, MD, DHL (Hon)


August 18, 2016

Competing When the Weather Is Hot

Another concern about the Games, Rio's water pollution, has also not emerged as a major problem. So far, only one athlete has reported any ill effects out of the 11,000 who are attending.[4]

Because it is winter in Brazil now, heat has not affected the athletes as severely as it might in summer. Temperatures in Manaus, the largest city on the Amazon, in the north-central part of the country, were forecasted to reach the 90s this week, but most venues, including those in Rio, on the southeastern coast, have seen temperatures in the 80s or lower.

That's still warm, and we took a number of precautions.

For soccer we have instituted a policy of cooling breaks. If the WetBulb globe temperature (WBGT)—which accounts for temperature, humidity, wind speed, sun angle, and cloud cover—reaches 32º C (89.7º F), we stop for 3 minutes at the 30th and 70th minutes to cool down. We pass out towels soaked in ice water, which drops the athletes' core temperature.

We instituted the first such cooling break in 2014 during the World Cup in Brazil, when Mexico was playing Holland. I was the person behind the scenes pulling it off.

Soccer is a very traditional game; you can't affect its integrity. We had to work with the media and the officials to optimize the game and the players' performance. In the beginning there was a lot of resistance, but ultimately we saw almost complete acceptance.

Strategies for Coping With Heat

Strategies for coping with heat vary from one sport to another. If you're working with a marathon runner or cyclist, you might schedule the event early in the day before temperatures rise. In soccer, you might hold the event later in the day when the WBGT sinks.

Some aspects of human physiology are simply adaptive techniques. We are built to adapt to heat better than many animals and primates do; our skin can lose heat, our sweating systems work, and we're not covered with hair like a dog or an ape.

This evolutionary adaptation goes back to a time when our ancestors practiced pursuit hunting. Running at a slow, steady pace, some early hominids could catch impalas and antelopes, which didn't have the capacity to regulate their temperatures as well and would overheat.

After chasing an animal for 2-3 hours, the only way our ancestors made it back to camp was to rehydrate by drinking the blood of their prey. This hypertonic fluid, high in salt, was the optimum drink.

In intense environments, if we try to rehydrate with just water, we can become hyponatremic. That's why I recommend sports drinks that contain a full complement of electrolytes to athletes competing during high temperatures.

I also recommend a comprehensive diet to maintain liver glycogen levels. People who eat a balanced diet and wish to avoid the carbohydrates in sports drinks may want to combine their water with a salt pill of the sort that American football teams have used for years.


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