When Matt Kenseth was invited by Jimmie Johnson to go for a casual bike ride in Iowa on Thursday, he should have known that it was going to be anything but that.

Kenseth joined Johnson for RAGBRAI Iowa, a seven-day bicycle ride across the state held each year. Johnson's group of riders also included former professional cyclist Lance Armstrong.

But, a "chill Thursday ride" turned into a grueling 103-mile journey for Kenseth.

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