A Comparison of Throwing Arm Kinetics and Ball Velocity in High School Pitchers With Overall Fast and Overall Slow Cumulative Joint and Segment Velocities.

BACKGROUND: Individual maximum joint and segment angular velocities have shown positive associations with throwing arm kinetics and ball velocity in baseball pitchers. PURPOSE: To observe how cumulative maximum joint and segment angular velocities, irrespective of sequence, affect ball velocity and throwing arm kinetics in high school pitchers. STUDY DESIGN: Descriptive laboratory study. METHODS: High school (n = 55) pitchers threw 8 to 12 fastball pitches while being evaluated with 3-dimensional motion capture (480 Hz). Maximum joint and segment angular velocities (lead knee extension, pelvis rotation, trunk rotation, shoulder internal rotation, and forearm pronation) were calculated for each pitcher. Pitchers were classified as overall fast, overall slow, or high velocity for each joint or segment velocity subcategory, or as population, with any pitcher eligible to be included in multiple subcategories. Kinematic and kinetic parameters were compared among the various subgroups using t tests with post hoc regressions and multivariable regression models created to predict throwing arm kinetics and ball velocity, respectively. RESULTS: The lead knee extension and pelvis rotation velocity subgroups achieved significantly higher normalized elbow varus torque (P = .016) and elbow flexion torque (P = .018) compared with population, with equivalent ball velocity (P = .118). For every 1-SD increase in maximum pelvis rotation velocity (87 deg/s), the normalized elbow distractive force increased by 4.7% body weight (BW) (B = 0.054; ß = 0.290; P = .013). The overall fast group was older (mean ± standard deviation, 16.9 ± 1.4 vs 15.4 ± 0.9 years; P = .007), had 8.9-mph faster ball velocity (32.7 ± 3.1 vs 28.7 ± 2.3 m/s; P = .002), and had significantly higher shoulder internal rotation torque (63.1 ± 17.4 vs 43.6 ± 12.0 Nm; P = .005), elbow varus torque (61.8 ± 16.4 vs 41.6 ± 11.4 Nm; P = .002), and elbow flexion torque (46.4 ± 12.0 vs 29.5 ± 6.8 Nm; P < .001) compared with the overall slow group. A multiregression model for ball velocity based on maximum joint and segment angular velocities and anthropometrics predicted 53.0% of variance. CONCLUSION: High school pitchers with higher maximum joint and segment velocities, irrespective of sequence, demonstrated older age and faster ball velocity at the cost of increased throwing shoulder and elbow kinetics. CLINICAL RELEVANCE: Pitchers and coaching staff should consider this trade-off between faster ball velocity and increasing throwing arm kinetics, an established risk factor for elbow injury.

Professional baseball pitchers produce similar ball velocity and kinematics when pitching from the wind-up and stretch deliveries: a biomechanical analysis.

Historically, the wind-up delivery is considered a more biomechanically advantageous pitching motion compared to the stretch. Recently, some pitchers have shifted to pitching exclusively from the stretch regardless of the game situation. The goal of this study was to compare temporal, kinematic and kinetic variables between the wind-up and stretch deliveries. Professional pitchers (n = 52, 189.1 ± 4.8 cm, 92.8 ± 8.4 kg) threw fastballs evaluated by 3D-motion capture (480 Hz) from both the wind-up and stretch deliveries. Within a pitcher, there was no significant difference in ball velocity between the two deliveries (p = 0.15). The stretch delivery was significantly quicker to ball release at toe off 2 (p < 0.001) (the last frame the pitcher's foot contacts the ground before progressing to maximum knee height) and maximum knee height (p < 0.001). The majority of differences occurred prior to foot contact. The wind-up delivery produced greater maximum shoulder external rotation (p < 0.001) and lead knee flexion at ball release (p < 0.001). Pitching from the stretch incurred greater shoulder superior force (p < 0.001). It remains unknown if this is clinically significant as pooled means show only a 2% difference. Therefore, pitching a fastball from either the wind-up or stretch delivery provides comparable mechanics and throwing arm load with likely comparable risk of injury.

Substance Use Outcomes For Sexual and Gender Minority Adults With a History of Adverse Childhood Experiences: A Scoping Review.

Purpose: The impacts of Adverse Childhood Experiences (ACEs) on behavioral, mental, and physical health have been extensively investigated. As such, it is paramount to synthesize their quantified effects, especially within vulnerable populations. The goal of this scoping review was to collect, summarize, and synthesize existing research on ACEs and substance use (SU) in adult sexual and gender minority (SGM) populations. Methods: WebofScience, APA PsychInfo, LGBTQ+ Life (EBSCO), Google Scholar, and PubMed electronic databases were searched. We included reports published between 2014 and 2022 that assessed SU outcomes, ACEs in adult (18+) SGM populations, in the United States (US). We excluded those in which SU was not an outcome, measured community-based abuse or neglect, or investigated adulthood trauma. Data were extracted using the Matrix Method and categorized across three SU outcomes. Results: Twenty reports were included in the review. Nineteen employed a cross-sectional design and 80% focused on a single SGM group (transgender women, bisexual Latino men, etc.). Nine of 11 manuscripts found SU frequency and quantity were higher among ACE exposed participants. Three of four studies found ACE exposure to correlate with substance use problems and substance misuse. Four of five studies found ACE exposure to be correlated with substance use disorders. Conclusions: Longitudinal research is needed to comprehend the impact of ACE on SU within the diverse subgroups of SGM adults. Investigators should prioritize the use of standard operationalizations of ACE and SU to improve comparability across studies and include diverse samples from the SGM community.