Higher expectations for MLB pitchers’ ‘stuff’ leading to pre-season injuries: report

New York — Pitchers traditionally report to Major League Baseball spring training camps by mid-February to ramp up throwing programs. Now a recent MLB report shows that overwork during the offseason is making today’s pitchers more likely to get injured before the regular season even starts.

The report resulted from analysis of pitcher placements on the injured list as well as interviews with more than 200 experts, including former professional pitchers, orthopedic surgeons and athletic trainers.

Findings show that, from 2010 to 2024, more than 1 out of 4 pitcher IL placements were related to elbow injuries that occurred in March – the highest of any month. March also saw the peak of other throwing-arm injuries, at around 1 out of 5 IL placements.

Pitcher placements on the IL have climbed sharply overall, from just more than 200 in 2005 to around 500 in 2024.

Numerous factors may play a role, including the rising velocity of fastballs and pitchers’ ongoing objective to refine their “stuff” – a term for how pitches spin and move.

As this push frequently takes place during the offseason, “the arm has less time to rest and recover from the previous season,” the study authors write.

“When is the time for pitch design and the time to tinker? The offseason,” one former MLB pitcher said in the report. “They say in golf that you practice on the range and you play on the course. You can’t try new swings on the course. In the season, your slider is your slider, unless the anatomy of that pitch really takes a dive. But during the offseason, if you’re not designing and refining, then guys are passing you by.”

Expert consensus shows that “creating a system where pitchers are encouraged or required to moderate their activity and throw at sub-maximum effort to go deeper into games may be better for pitcher health.”

Glenn Fleisig, director of biomechanics research at the American Sports Medicine Institute and injury research adviser to MLB, said in a press release that the report represents an “encouraging” first step toward improving pitcher health.

“Major League Baseball is investing the time and personpower to do this,” Fleisig said. “MLB is trying to understand and prevent the injury epidemic. I think this helps to point out that we are serious about this.”