Has Limiting Innings Now Gone Too Far?




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Given the modern approaches to pitching, Dwight Gooden's 1983 season at high Class A Lynchburg will never again be equaled.

As amazing as Dylan Bundy's pro debut has been, it doesn't begin to compare to what Gooden did in his first full pro season. The Mets 1982 first-round pick struck out a mind-boggling 300 batters in 191 innings at high Class A Lynchburg. He threw 10 complete games in 27 starts. He also walked a league-high 112 batters. When the Carolina League season ended, he was promoted to Triple-A Tidewater for the playoffs, where he struck out 19 more in the playoffs.

Pitch counts and innings limits were still something for the distant future at the time, as pitchers pitched until they couldn't pitch any more. While the pitch counts for Gooden's starts have been long forgotten, the combination of plenty of walks and strikeouts ensured he was going well beyond 100 pitches on a regular basis.

Breaking Down
Of the 103 high school pitchers selected in the first round since 1992, 48 missed a significant portion of at least one of their first six seasons. Here is the breakdown of the injuries and other reasons pitchers missed significant time.
Shoulder injury 19
Elbow injury 14
Elbow and
Shoulder injuries
5
Drugs 2
Released/Quit 2
Hand injury 1
Asthma attack
(death)
1
Car accident
(death)
1
Broken
non-throwing arm
1
Nerve problem 1
Mental health 1
It's hard to find any reputable expert these days willing to let a young pitcher throw 200-plus innings in his first full season, but there also is no real consensus on how many innings are too many. Orioles pitching coordinator Rick Peterson did cite an American Sports Medicine Institute study that found that amateur pitchers who threw more than 100 innings in a season were 3.5 times more likely to be injured than those who threw less than 100 innings, but that was a study of pitchers who were ages 9 to 14 at the beginning of the study. No similar study of professional pitchers has been made public.

To get a better sense of whether limiting innings helps ensure the long-term health of a pitcher, Baseball America studied every high school pitcher selected in the first round from 1992 to 2007. BA determined whether each pitcher made the big leagues, pitched more than 150 innings in the big leagues. BA also compiled whether those with 150-plus big league innings have an ERA+ in the big leagues of 90+ or threw more than 500 total big league innings.

Each pitcher's first six full pro seasons were logged to see if they missed a significant amount time in one season, or a combination of back-to-back seasons. This was done by logging any season where a pitcher threw less than 30 innings or back-to-back seasons with less than 40 innings pitched. If a pitcher missed significant time, the reason for the absence was also determined.

For the purposes of the study, Rockies pitcher Doug Million, who died of an asthma attack, and Padres pitcher Gerik Baxter, who died in a car accident, were excluded. Also pitchers who missed their first full pro season (Jeff Allison, Matt Roney and Jeff D'Amico) as well as those who pitched less than 40 innings their first season (Chris Withrow, Chris Gruler, Matt Wheatland, Tony McKnight and Andrew Yount) were excluded, since all were injured or otherwise sidelined before they pitched a full pro season. Pitchers drafted since 2007 were excluded since many haven't had a legitmate chance to make the majors yet, and they have also had less time to prove their durability.

The average innings pitched in the first full season for the remaining 76 pitchers was 110 innings. The standard deviation was 39 innings, so the groups were divided into pitchers who threw less than 71 innings (one standard deviation below), those that threw 71-149 innings and those that threw more than 149 innings (one standard deviation above).

What we found is that the pitchers who threw more innings during their first full season were significantly more likely to make the majors and less likely to be injured. On the other hand, those who threw less than 71 innings in their first full pro season were significantly more likely to be injured and less likely to reach the majors.

PLENTY OF INNINGS
In studying every high school pitcher signed in the first round since 1992, the five who threw the most innings pitched during their first full season form a pretty illustrious group.
Player Year Team IP
Roy Halladay 1996 HiA Dunedin 165
Adam Wainwright 2001 LoA Macon 165
Gavin Floyd 2002 LoA Lakewood 166
Jake Westbrook 1997 LoA Asheville 170
Brett Myers 2000 LoA Piedmont 175
There are some factors that would make the group of pitchers that threw at least 149 innings more likely to have long-term success. For one, those pitchers demonstrated both durability (all made at least 25 starts) and ability to work effectively in their first season—to log that many innings a pitcher had to average at least five innings per outing. Also, the fact that their team would let them throw that many innings generally indicates that there was a belief that the pitcher's frame and delivery was ready for a heavy workload.

But many pitchers with good frames and clean deliveries are currently limited to throwing significantly less innings in their first full season because of the belief that it will help them stay healthier over the long-term. In studying first round high school pitchers, the data doesn't appear to show any such benefits.

Success Rates By Innings Pitched
IP first
full season
No. of
Pitchers
Pct Making
Majors
Pct Injured
first 6 seasons
Pct 150+
MLB IP
Pct 150+ IP
with ERA 90+
Less than 71 12 42% 58% 25% 25%
71-149 47 55% 51% 40% 34%
149+ 15 93% 27% 60% 60%