, Hassell N , Andrews JR . Prevention of elbow injuries in youth baseball pitchers . Curr Sports Med Rep . 2009 ; 8 ( 5 ): 250 – 254 . PubMed doi:10.1249/JSR.0b013e3181b7ee5f 10.1249/JSR.0b013e3181b7ee5f 19741352 2. Lyman S , Fleisig GS , Waterbor JW
Noah X. Tocci, David R. Howell, Dai Sugimoto, Corey Dawkins, Amy Whited and Donald Bae
Dong-Rour Lee and Laurentius Jongsoon Kim
Many studies have explored closed kinetic chain (CKC) shoulder exercises (SEs) with a sling because they are safer and more effective than open-chain exercises, especially in early stages of treatment. However, the application of CKC SE in youth baseball players has rarely been attempted, although teenage baseball players also experience shoulder pain.
To investigate the effects of CKC SE on the peak torque of shoulder internal rotation (IR) and external rotation (ER) in youth baseball players.
Single-group pretest, posttest.
23 Little League Baseball players with subacromial impingement syndrome.
The CKC SE with a sling was CKC shoulder-flexion exercise, extension exercise, IR exercise, and ER exercise. This exercise regimen was conducted 2 or 3 times/wk for 8 wk.
Main Outcome Measures:
The peak torque of shoulder IR and ER was measured using an isokinetic dynamometer. Concentric shoulder rotation was performed, with 5 repetitions at an angular velocity of 60°/s and 15 at 180°/s.
The IR and ER peak torque significantly increased at each angular velocity after the exercise program. In particular, the increase in IR and ER peak torque values was statistically significant at an angular velocity of 180°/s.
CKC SE was effective in increasing shoulder IR and ER strength, demonstrating its potential benefits in the prevention and treatment of shoulder injury. In addition, increased IR peak torque appears to improve throwing velocity in baseball players.
Joseph J. Crisco, Michael J. Rainbow, Joel B. Schwartz and Bethany J. Wilcox
The purpose of this study was to examine the batting cage performance of wood and nonwood baseball bats used at the youth level. Three wood and ten nonwood bats were swung by 22 male players (13 to 18 years old) in a batting cage equipped with a 3-dimensional motion capture (300 Hz) system. Batted ball speeds were compared using a one-way ANOVA and bat swing speeds were analyzed as a function of bat moment of inertia by linear regression. Batted ball speeds were significantly faster for three nonwood bat models (P < .001), significantly slower for one nonwood model, and not different for six nonwood bats when compared with wood bats. Bat impact speed significantly (P < .05) decreased with increasing bat moment of inertia for the 13-, 14-, and 15-year-old groups, but not for the other age groups. Ball-bat coefficients of restitution (BBCOR) for all nonwood were greater than for wood, but this factor alone did not correlate with bat performance. Our findings indicate that increases in BBCOR and swing speed were not associated with faster batted ball speeds for the bats studied whose moment of inertia was substantially less than that of a wood bat of similar length.
Jess C. Dixon, Laura Chittle and Sean Horton
The relative age effect (RAE) has become a well-studied consequence of organizations utilizing a cutoff date to establish age cohorts. Within this case study, students will explore and learn how to perform various statistical analyses (i.e., chi-square, effect sizes, standardized residuals) to determine whether the RAE exists among those who competed in the 2011 and 2012 Little League World Series (LLWS). Students will learn about the mission and history of Little League Baseball (LLB) and discuss potential changes and/or strategies that could be used by the organization to make the LLWS more inclusive. Furthermore, students can use the knowledge gained from this case study to critically analyze the current status of various other sport organizations to help develop potential strategies to ensure fairness and equality for all participating athletes.
Leonardo Ruiz, Judy L. Van Raalte, Thaddeus France and Al Petitpas
steroids manufactured for horses and cattle from veterinarians ( Bouchet et al., 2013 ; Storms, 2008 ). Once amateur youth baseball players sign a professional contract, they are assigned to the MLB’s affiliated baseball academies, where they receive immediate benefits. The academies offer equipment
Joseph J. Crisco, Nikolas J. Osvalds and Michael J. Rainbow
study was to compute the forces and moments required to swing baseball bats. We selected 3 baseball bat models with a range of bat MOIs that had been previously used in a study of youth baseball bat performance. 7 Given this range of MOIs, we also sought to determine if the peak forces and moments
Nick B. Murray, Georgia M. Black, Rod J. Whiteley, Peter Gahan, Michael H. Cole, Andy Utting and Tim J. Gabbett
Throwing loads are known to be closely related to injury risk. However, for logistic reasons, typically only pitchers have their throws counted, and then only during innings. Accordingly, all other throws made are not counted, so estimates of throws made by players may be inaccurately recorded and underreported. A potential solution to this is the use of wearable microtechnology to automatically detect, quantify, and report pitch counts in baseball. This study investigated the accuracy of detection of baseball pitching and throwing in both practice and competition using a commercially available wearable microtechnology unit.
Seventeen elite youth baseball players (mean ± SD age 16.5 ± 0.8 y, height 184.1 ± 5.5 cm, mass 78.3 ± 7.7 kg) participated in this study. Participants performed pitching, fielding, and throwing during practice and competition while wearing a microtechnology unit. Sensitivity and specificity of a pitching and throwing algorithm were determined by comparing automatic measures (ie, microtechnology unit) with direct measures (ie, manually recorded pitching counts).
The pitching and throwing algorithm was sensitive during both practice (100%) and competition (100%). Specificity was poorer during both practice (79.8%) and competition (74.4%).
These findings demonstrate that the microtechnology unit is sensitive to detect pitching and throwing events, but further development of the pitching algorithm is required to accurately and consistently quantify throwing loads using microtechnology.
Rafael F. Escamilla, Glenn S. Fleisig, Coop DeRenne, Marcus K. Taylor, Claude T. Moorman III, Rodney Imamura, Edward Barakatt and James R. Andrews
We propose that learning proper hitting kinematics should be encouraged at a young age during youth baseball because this may help reinforce proper hitting kinematics as a player progresses to higher levels of baseball in their adult years. To enhance our understanding between youth and adult baseball hitting, kinematic and temporal analyses of baseball hitting were evaluated with a high-speed motion analysis system between 12 skilled youth and 12 skilled adult baseball players. There were only a small number of temporal differences between youth and adult hitters, with adult hitters taking significantly greater time than youth hitters during the stride phase and during the swing. Compared with youth hitters, adult hitters a) had significantly greater (p < .01) lead knee flexion when the hands started to move forward; b) flexed the lead knee over a greater range of motion during the transition phase (31° versus 13°); c) extended the lead knee over a greater range of motion during the bat acceleration phase (59° versus 32°); d) maintained a more open pelvis position at lead foot off ground; and e) maintained a more open upper torso position when the hands started to move forward and a more closed upper torso position at bat-ball contact. Moreover, adult hitters had greater peak upper torso angular velocity (857°/s versus 717°/s), peak left elbow extension angular velocity (752°/s versus 598°/s), peak left knee extension angular velocity (386°/s versus 303°/s), and bat linear velocity at bat-ball contact (30 m/s versus 25 m/s). The numerous differences in kinematic and temporal parameters between youth and adult hitters suggest that hitting mechanics are different between these two groups.
Baseball. In the fourth chapter, The Eternal and Ever-Changing Game , the author sheds light on how the current state of youth sport in general, and youth baseball in particular, may be negatively affecting the way Major League Baseball is consumed by young people and how young ballplayers might be
Rafael F. Escamilla, Jonathan S. Slowik, Alek Z. Diffendaffer and Glenn S. Fleisig
stretch in professional baseball pitchers . Am J Sports Med . 2008 ; 36 ( 1 ): 137 – 141 . PubMed ID: 17986632 doi:10.1177/0363546507308938 10.1177/0363546507308938 17986632 14. Dun S , Loftice J , Fleisig GS , Kingsley D , Andrews JR . A biomechanical comparison of youth baseball pitches