The NFL rulebook says nothing about wetsuits, so Matt Barkley should be good.
Due to frigid temperatures in Chicago on Sunday, the Bears quarterback planned to wear the upper part of a two-piece wetsuit under his uniform against the Packers, according to NFL.com.
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Triathletes employ a similar trick "to keep their core warm when partaking in frigid conditions," according to the report.
Barkley, 26, was slated to make his fourth consecutive start for the Bears on Sunday in place of injured starter Jay Cutler.