How cold weather will impact marathon runners this weekend

HOUSTON – Thousands of runners Friday will flock to GRB Stadium to pick up their race packets for Sunday's marathon. 

The big difference you can feel from last year to this year is the weather. In 2017, it was very hot, humid and muggy on race day. It caused a lot of athletes to visit the medical tents due to heat exhaustion. 

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This year, it will be the exact opposite.

It will be cool, crip and perfect for running conditions, according to Dr. John Cianca, the marathon's medical director. 

"With weather being probably in the 50s, low 50s and it being sunny, that's ideal -- it allows the body to dissipate heat," Cianca said. 

While heat exhaustion won't likely be a factor this year, flu season might be. 

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"If people have been ill lately, have had a fever, they need to back off their pace or maybe not even participate, depending on how close the illness has been," Cianca said.

Cianca advises athletes to wear warm clothes they can easily take off when their bodies warm up. Race officials said volunteers will be along the race route to collect those clothes and they will be donated to various charities in need.