Researchers tracked 259 elite rugby players in the 2010 Super 14 Rugby Tournament. The 16 weeks of games took place in Australia, South Africa and New Zealand.

 

On average, there were 21 illnesses per thousand player-days. But players in their home countries endured only 15 illnesses per thousand days. And when a team traveled more than five time zones in either direction, illnesses rates more than doubled. The number dropped back to 10 after they flew back home. The illnesses were primarily infections, such as respiratory or intestinal illnesses.

 

A weakened immune system does not appear to be a factor. The researchers suggest that differences in temperature, pollution, allergens and different foods and local microbes are the likeliest culprits. One more element that might give European Olympians a home field advantage.

 

Thanks for the minute for scientific American sixty seconds science. I'm Cynthia Graber. 

 

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