After a Twitter prank, U.S. 1,500-meter runner Kyle Merber spurred a debate over what LeBron James can run for 400-meters.

What started off as a silly prank to fetch retweets spurred a Twitter debate as to what LeBron James could run for a 400-meter dash.

While preparing for the 1,500-meter final at the 2015 Pan American Games in Toronto, U.S. 1,500-meter runner Kyle Merber tweeted, "If this gets 1000 RTs @KingJames said he'll race the 400m."

James is not even competing for men's national team at the Pan American Games, yet fans believed the agreement between Merber and James took place.

Among those with a significant amount of Twitter followers that helped spur the successful push for 1,000 retweets were SportsCenter anchor Jay Crawford and Olympians Andrew Wheating and Jesse Williams. The goal was reached on Wednesday morning before Merber admitted, "So just for the record, @KingJames and I never actually spoke about this 400...I was lying."

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The prank opened the floor for predictions as to what James could run for the quarter-mile distance. ESPN's Jay Crawford, whose son Corey jumps for Rutgers, predicts an optimistic sub-50 second lap.

ProPublica writer and The Sports Gene author David Epstein predicts a sub-60 second performance if James lost weight, but also left the door open for a slower time.

Other notable personalities in track and field and sports medicine followed up:

One thing is certain, James would have to train hard to match Robert Griffin III's personal records from his days as a hurdler for Baylor and as a 400-meter high school runner.

- Christopher Chavez