The heat is on the world's best soccer players, who will start competing in Brazil for the 2014 World Cup next week. But in case the heat is more than figurative, some teams are relying on new technologies to physically cool their bodies before they play.
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New ice vests from Adidas, for example, were so popular with the German team during testing that the company outfitted all of their teams with the "precooling" vests and sleeves.
The garments, which hover near freezing temperatures for up to 20 minutes, focus on the lower arms and upper back, which the company says it's found to be the most efficient areas of the body to cool. Intended to be worn during warmup and half-time, the vest and sleeves are soaked in water, squeezed out, and then placed in a freezer before the next use.
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Although it's winter in Brazil, temperatures are still often in the 80s with high humidity. Acclimating to such conditions can take a couple of weeks, so some teams have been moved their training camps to warmer locations. The Italians have been training in saunas, running on treadmills in rooms heated to 91 degrees with 70 percent humidity. Others have donned extra layers of clothing.
"We've tried to reproduce the environmental conditions that we will likely find, above all in Manaus, but also in Recife and Natal," team physician Enrico Castellacci told Fox News. "Players work on a specific program and then we evaluate their resistance to the fatigue, by monitoring their heartbeat and weight before and after the exercises."
World Cup rules have changed since 1994 to allow for additional water breaks.