Pitch counts are a measure used in baseball, at all levels, to help gauge when a pitcher has done too much work and is at risk for an injury. The thought is that the greater the pitch count the more at risk a pitcher is. This is accepted in Little League all the way through the major leagues. In the August issue of the Journal of Strength and Conditioning Research, Karakolis et al argue this concept by attempting to see if work measures predict injuries in Major League Baseball pitchers.
To perform this study, the authors collected pitching statistics for the 2002-2007 baseball seasons and compared that with injury data. The results are very interesting:
- When looking at the number of innings pitched, the percentage of pitchers who were injured and who pitched between 41 and 120 innings for the season is in the low to mid 30%. The percentage of pitchers who were injured and who pitched 121-220 innings is in the 35% to 45% range.
- When looking at the total number of pitches thrown in a season, the number of pitchers injured are in the 20-30 percentages (these are pitchers who threw either less than 1801 pitches per season or who threw more than 2400 pitches per season), except for pitchers who pitched between 1801-2400 pitches per season, which are in the low 40%.
- When looking at number of pitchers thrown per game, from 21 to 120 the percentage of pitchers injured basically increases as the number of pitches thrown per game does. This is from around 20% at 21-30 pitches/game to 40% at 111-120 pitches/game.
According to the authors, when all the above data is thrown into a regression equation none of the variables is a statically strong predictor on injuries. In other words, in terms of statistics the trends are interesting but they are not significant. However, the fact that the percentage of players getting injured increases as they throw more pitches in a game would seem to be very important and would seem to reinforce the importance of using the pitch count to monitor throwing load.
There is another interesting statistic that stands out to me. Regardless of how much they pitch, 20-40% of Major League Baseball pitchers are going to get injured. This reinforces the importance of good mechanics and conditioning. It also reinforces the need for the strength coach and the pitching coach to be working together so that the player’s pitching volume is taken into account when implementing a conditioning program.
Karakolis, T., Bhan, S., and Crotin, R.L. (2013). An inferential and descriptive statistical examination of the relationship between cumulative work metrics and injury in Major League Baseball pitchers. Journal of Strength and Conditioning Research, 27(8): 2113-2118.
