Limiting the number of innings that young professional pitchers pitch doesn't reduce their risk of arm injuries, a new study says.
The study also found that gradually increasing the total number of innings pitched has no effect on the risk of future injury.
"Conventional wisdom among coaches and managers is that restricting innings for young starting pitchers, and slowly increasing the number of innings pitched over several years, gives pitchers' tissues sufficient time to adapt to the workload of a major league season," said lead investigator Thomas Karakolis, of the University of Waterloo in Canada.
"But all our data shows that these strategies really make no difference in preventing injury," he added in a university news release.
The researchers analyzed data collected between 2002 and 2007 from pitchers younger than 25 who had pitched at least one-third of an inning in Major League Baseball.
A year-to-year increase of 30 innings pitched is often used as the limit for a young starting pitcher. But the researchers found no consistent link between injuries and the number of innings pitched or the rate of yearly increases in innings pitched.
"Injury is the result of workload exceeding the capacity of the body's tissues, so while counting innings is a tempting way to measure workload, it's actually a very flawed method," Karakolis said.
"If coaches are looking for ways to prevent injury, simply limiting the number of innings is not the answer. They have to look at how hard a pitcher's body is working during each inning, each pitch," he added.
The study suggests that teams need to invest in "biomechanical assessments for each pitcher" to try to prevent injuries. And, coaches and trainers should consider strength and conditioning programs that focus on soft tissue, the researchers said, adding that younger pitchers have a better chance at tissue adaption than older pitchers.
Injuries have been a big problem for Major League Baseball in recent years, with more than 25 percent of pitchers winding up on the disabled list, the study authors said.
The study was published online recently in the Journal of Sports Medicine and Physical Fitness.
-- Robert Preidt