Zumaya once reached the outer limit but his speed caught up with him

Physiology can only take us so far. Throwing a ball is not a normal motion that can be repeated infinitely. And once you're on the outer limits of just how fast that ball can be thrown, the body will react.

That seems a plausible explanation for the right arm of Joel Zumaya.

Zumaya in 2006 for the Detroit Tigers threw the fastest pitch ever recorded by a radar gun: 104.8 mph. He hasn't been the same since. He's had his elbow reconstructed twice and had myriad other injuries since then (one sustained, famously, playing "Guitar Hero"). He missed the entire 2011 season with a broken elbow, and was signed to an incentive-laden deal by the Minnesota Twins in the offseason.

After 13 pitches in the Twins camp on Saturday, he left with elbow pain. And an MRI showed he had a torn ulnar collateral ligament in the same elbow, ending his 2012 comeback before it even began.

While the human body finds ways to break records in track and field and swimming all the time, peak velocity seems to have been reached in baseball. A story in Slate back in 2005 quoted experts in biomechanics why.

"Why do sprinters keep getting faster while baseball pitchers seem to have maxed out? Because track athletes don't approach the limits of what human tendons and ligaments can handle. When you run the 100-meter dash, no single stride represents as violent a motion as the arm makes during a single overhand pitch. Sprinters can build up their muscles without worrying that the extra force will rip their ligaments apart."

Science 2.0 also has an interesting article on the science of how fast a human can throw a baseball.

Zumaya left camp without speaking on his injury, which might require Tommy John ligament transplant surgery if Zumaya wants to keep going.

"The kid's a really good kid," manager Ron Gardenhire said to the St. Paul Pioneer Press. "You get to know people from the other side, and he looks like some monster out there pitching against you. But you get him in your clubhouse, and you realize there are special people, and he's a special person, and it's a really sad day for him and his family and our baseball team, too. We were all hoping this guy would be able to get back on this thing and make it through. Unfortunately, it didn't work out."

Zumaya, 27, might be done as a major-league pitcher. Meanwhile, Jamie Moyer, 49, is still pitching in camp with the Rockies.

One threw the hardest; the other one of the softest.

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