'Sports Illustrated' Ranks LeBron As The Second Fittest Athlete in The World. See Who Beat Him Out For Number One

Guess who ranks ahead of LeBron James on SI's Fittest 50 list.

Sports Illustrated released their Fittest 50 earlier today, a project which aims to rank the fittest athletes on planet Earth. As for the criteria, the authors write that "athletes were assessed based on strength, speed, endurance, agility, flexibility and skill in his or her respective sport."

As expected, the Fittest50 is filled with freaks like Usain Bolt, Cristiano Ronaldo and Russell Westbrook. But ahead of all those names is none other than LeBron James, whom SI ranks as the second fittest male athlete in all of sports. "From his explosive energy on a breakaway, to his power on a strong drive to the basket and his ability to sprint and smoothly finish at the rim, King James reigns in all areas of fitness," the authors write.

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LeBron is a 6-foot-8, 250-pound freight train of unstoppable energy, so it is easy to understand why SI ranked him so high. His unbelievable pure athleticism allows him to excel in all facets of the game, and his elite conditioning makes him lethal in crunch time. Perhaps the biggest surprise of the Fittest50 is that LeBron is not ranked number one. Who the heck is more fit than King James?

According to SI, that man is Ashton Eaton. Although his name lacks the instant recognition and star power as LeBron's, there's no doubt Eaton is a freak. The 28-year-old American track & field athlete currently holds the world record in the decathlon. He was a five-time NCAA champion at the University of Oregon and won a gold medal at the 2012 Summer Olympics.

"Traditionally, the world record holder in the decathlon has been known as 'the world's greatest athlete,'" the authors write. "In Eaton's case, let's add 'world's fittest,' as well. With 10 very different events to prepare for, the current record holder—and 2012 Olympic champion—has to touch on every element of physical and mental conditioning every day. Pointing for a title defense in Rio, Eaton is hitting new heights in his routine."

The decathlon is an incredible test of athletic versatility. The winner must excel in everything from the 400-meter dash to the Discus Throw to the High Jump. The 6-foot-1, 185-pound Eaton does exactly that, making him worthy of the distinction of world's fittest athlete.

To get a better idea of how freakish Eaton really is, watch the highlights from his world record run:

Check out the full project (which also includes a list of the 50 fittest women in sports) on SI.com and check out Eaton's Instagram page to get a glimpse of the workouts that power the world's fittest athlete.

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