Youth Baseball Pitch Counts Vastly Underestimate High-effort Throws Throughout a Season.

BACKGROUND: The primary purpose of this study was to compare the number of pitches thrown by youth baseball players under the official league guidelines versus the number of "high-effort" throws recorded by a validated digital sensor worn by the players during a season. METHODS: In total, 11 and 12-year-old youth baseball players from a single league were provided an elbow sleeve and sensor to wear each time they threw a baseball for an entire baseball season. The sensor tracked total throws and pitch-equivalent high-effort throws for the season. Official pitch counts were collected at each game from the official scorekeepers. RESULTS: A total of 19 players participated in the study. The sensor-determined mean total throw count (1666.2±642.2) and mean high-effort throw count (576.9±329.3) per player were both significantly higher, P<0.0001 and P=0.02, respectively, than the mean official pitch count (168.1±122.4). CONCLUSIONS: Our findings demonstrate that youth players make significantly more total throws and high-effort, or pitch-equivalent, throws, than what is recorded by the official pitch counts. Further research is needed to determine a safe annual "throw count" for young throwing athletes and to determine which types of throws, in addition to pitches, put youth throwers at risk for injury. LEVEL OF EVIDENCE: Level IV.

Batting performance of wood and metal baseball bats.

INTRODUCTION/PURPOSE: Although metal baseball bats are widely believed to outperform wood bats, there are few scientific studies which support this. In a batting cage study, Greenwald et al. found that baseballs hit with a metal bat traveled faster than those hit with a wood bat, but the factors responsible for this difference in bat performance remain unidentified. The purpose of this study was to determine the effects of swing speed, impact location, and elastic properties of the bat on batted ball speeds. METHODS: The pitched ball, batted ball, and swings of two wood and five metal baseball bats by 19 different players were tracked in three dimensions at 500 Hz using a passive infrared motion analysis system. RESULTS: Increases in the batted ball speeds of metal bats over those of wood bats resulted from faster swing speeds and higher elastic performance with an apparent increase in the ball-bat coefficient of restitution. The contribution of these variables to batted ball speed differed with metal bat model. The "sweet spot" associated with maximum batted ball speeds was located approximately the same distance from the tip of wood bats as it was from metal bats. CONCLUSIONS: The variables that correlated with differences between metal and wood bat performance, and most notably differences in the percentage of faster batted balls, were identified using a novel kinematic analysis of the ball and bat. These variables and their correlation with bat performance should be applicable to other players and bats, although more skilled players and higher performing bats would likely result in even faster batted ball speeds.

Reduced risk of sudden death from chest wall blows (commotio cordis) with safety baseballs.

OBJECTIVES: In an experimental model of sudden death from baseball chest wall impact (commotio cordis), we sought to determine if sudden death by baseball impact could be reduced with safety baseballs. BACKGROUND: Sudden cardiac death can occur after chest wall impact with a baseball (commotio cordis). Whether softer-than-standard (safety) baseballs reduce the risk of sudden death is unresolved from the available human data. In a juvenile swine model, ventricular fibrillation (VF) has been shown to be induced reproducibly by precordial impact with a 30-mph baseball 10 to 30 ms before the T-wave peak, and this likelihood was reduced with the softest safety baseballs (T-balls). To further test whether safety baseballs would reduce the risk of sudden death at velocities more relevant to youth sports competition, we used our swine model of commotio cordis to test baseballs propelled at the 40-mph velocity commonly attained in that sport. METHODS: Forty animals received up to 3 chest wall impacts at 40 mph during the vulnerable period of repolarization for VF with 1 of 3 different safety baseballs of varying hardness, and also by a standard baseball. RESULTS: Safety baseballs propelled at 40 mph significantly reduced the risk for VF. The softest safety baseballs triggered VF in only 11% of impacts, compared with 19% and 22% with safety baseballs of intermediate hardness, and 69% with standard baseballs. CONCLUSION: In this experimental model of low-energy chest wall impact, safety baseballs reduced (but did not abolish) the risk of sudden cardiac death. More universal use of these safety baseballs may decrease the risk of sudden death on the playing field for young athletes.

Sliding-associated injuries in college and professional baseball--1990-1991.

Softball and baseball are among the most frequent causes of sports-related emergency department visits in the United States, accounting for an estimated 321,000 injuries in 1989. Approximately 71% of softball-related injuries are caused by sliding. The use of breakaway bases substantially decreases the risk for or occurrence of sliding-related injuries among recreational softball league players. This report summarizes the findings of a study on the impact of breakaway base use on sliding injuries among college and professional minor league baseball players.