Paul Ryan's campaign walked back comments the VP nominee made about running a marathon.

"I had a two hour and fifty-something" marathon, Ryan said last week an interview. "I hurt a disc in my back, so I don’t run marathons anymore."

But the Ryan campaign confirmed to Runner's World that he has only run one marathon, the 1990 Grandma’s Marathon in Duluth, Minnesota, which he finished in just over 4 hours.

"The race was more than 20 years ago, but my brother Tobin—who ran Boston last year—reminds me that he is the owner of the fastest marathon in the family and has never himself ran a sub-three," Ryan said in a prepared statement. "If I were to do any rounding, it would certainly be to four hours, not three. He gave me a good ribbing over this at dinner tonight."

The admission comes after wide speculation that Ryan had exaggerated his marathon time. Running a sub-3 hour marathon means averaging under 7 minutes per mile for the entire race, a possible but extremely impressive feat. As the New Yorker's Nicholas Thompson put it, "It’s the difference between racing and running."

This isn't the first time Ryan has come under fire this week for stretching the truth. His RNC speech was chastised for misleading claims about Medicare and the 2008 closing of a Wisconsin plant.

The running fib "sounds trivial," wrote the New York Times' Paul Krugman. "But I remember the 2000 campaign, when Al Gore was constantly hounded by claims of fibbing on trivial issues — claims that, by the way, were all, as far as I could tell, fabricated. These alleged fibs supposedly showed some deep defect in his character. So if Ryan is making false claims about his physical prowess, this is absolutely fair game."

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