Pitch Type Research Articles

Comparison of In-Game Trunk and Upper Extremity Kinematics Between Fastballs, Breaking Balls, and Changeups in NCAA Division I Collegiate Baseball Pitchers.

Previous biomechanical analyses of baseball pitching report similar kinematics between pitch types. However, prior studies were conducted in a controlled laboratory environment. This study aimed to compare in-game trunk and upper extremity kinematics between fastballs, breaking balls, and changeups to determine whether there are kinematic differences that may affect performance as well as to provide new insights into potential risk factors for injury. It was hypothesized that there would be kinematic differences between pitch types. Descriptive laboratory study. A retrospective analysis was conducted of markerless motion capture data collected during National Collegiate Athletic Association Division I baseball games. Included were 34 pitchers who pitched at least 3 pitches of each type (fastball, breaking ball, changeup) during competition. A 1-way repeated-measures multivariate analysis of variance (MANOVA) was used to test differences between pitch types, and Bonferroni post hoc tests were used to test pairwise comparisons. The MANOVA revealed a significant effect of pitch type (P < .001), and follow-up univariate tests found a significant main effect of pitch type for 12 of the 15 kinematic variables analyzed. Post hoc Bonferroni tests revealed that maximum shoulder external rotation was significantly greater during fastballs than breaking balls. At foot contact, significantly less shoulder external rotation was seen during changeups compared with fastballs and breaking balls. At the time of ball release, changeups had significantly less trunk lean and less trunk flexion than fastballs and breaking balls, and fastballs had a significantly smaller arm slot angle than breaking balls and changeups. Collegiate baseball pitchers displayed numerous kinematic differences between pitch types during competitive play, some of which are known influencers of pitching kinetics. This study offers a novel perspective regarding kinematic differences between different pitch types during competition. These results are comparable to the findings of laboratory studies and provide valuable insights into potential injury mechanisms.

Varus Strength of the Medial Elbow Musculature for Stress Shielding of the Ulnar Collateral Ligament in Competitive Baseball Pitchers.

Valgus load opens the medial elbow compartment, causing elongation of the ulnar collateral ligament (UCL) that can eventually lead to attenuation and failure. Ideally, the muscles surrounding the medial aspect of elbow joint should coordinate medial elbow compression to prevent the medial elbow compartment from opening and loading the UCL. This study aimed to determine whether baseball pitchers have sufficient elbow varus strength to unload the UCL during pitching. Using an electromagnetic tracking device, we measured the peak elbow varus moment during pitches (fastball, slider, curveball, and changeup) by 14 professional and 8 collegiate pitchers. Elbow varus strength was measured with an isokinetic dynamometer system while the medial elbow joint space was monitored using ultrasonography. A paired t-test was used to compare the peak varus moment generated during pitching with the varus strength, and the relative intensity of muscular output required to unload the UCL was determined. Except for curveballs, the muscular varus strength (57.5 ± 9.2 N·m) was not significantly larger (p = 0.165 ~ 0.853) than the peak varus moments during pitching (55.4 ± 13.0 N·m). Ten participants did not have sufficient muscular varus strength to completely unload the UCL from valgus loading when throwing fastballs and other pitch types. The relative intensity of muscular torque output required for stress shielding of the UCL ranged from 89.1%MVIVS ±21.7%MVIVS for curveballs to 103.1%MVIVS ±26.5%MVIVS for fastballs. Our findings demonstrate that most of the valgus load on the elbow joint during pitching can be counteracted by the muscular varus moment, but valgus loading on the UCL is likely unavoidable in baseball pitching.

Effects of a Simulated Game and Doubleheader Inning on Peak Kinetics in Softball Pitching Across Pitch Types

Background: Softball pitchers frequently pitch at high volumes. Previous research has demonstrated changes in mechanics, range of motion, and perceived levels of fatigue and pain at high workloads. To date, little research has assessed changes in kinetics at high workloads across pitch types to understand the injury risk. Purpose: To examine changes in peak kinetics of the shoulder, elbow, and wrist of the pitching arm throughout a simulated game and doubleheader inning. Study Design: Descriptive laboratory study. Methods: A total of 19 high school softball pitchers (mean age, 15.1 ± 1.5 years; mean height, 1.6 ± 0.2 m; mean weight, 76.3 ± 16.9 kg) participated. Pitchers threw 4 innings of 25 randomly assigned pitches to mimic a game's high pitch count. Participants then rested for 30 minutes before subsequently proceeding to pitch the first inning of a doubleheader. Each pitcher threw a fastball, drop ball, curveball, and changeup. Peak shoulder, elbow, and wrist kinetics were compared across the first, last, and doubleheader innings and pitch types. Results: Compared with the first inning, significant decreases in kinetics were observed at the shoulder, elbow, and wrist in the last (P < .016) and doubleheader (P < .016) innings, particularly for shoulder and elbow compression force during the drop ball and curveball pitch types and wrist net force for all pitch types but the changeup. Significant decreases in elbow and wrist kinetics were observed during the changeup between the last and doubleheader innings (P < .016). Furthermore, differences in kinetics were observed between pitch types (P < .008); notably, the changeup had reduced kinetics compared with the fastball and breaking ball pitch types (drop ball, curveball) across innings. Conclusion: Across innings, attenuations in select joint kinetics of the pitching arm occurred that were specific to the pitch type. Across pitch types, peak kinetics was often greater during the fastball, while the changeup displayed the lowest peak kinetics. Clinical Relevance: The joints examined in this study are common sites of overuse injuries in pitchers. This work adds to previous findings on decrements in neuromuscular function as well as self-reported fatigue and pain with tournament-style pitching that may increase the injury risk. Collectively, these findings support developing a protocol combining functional testing and player-reported outcomes to aid sports specialists’ decisions for pitchers to continue to pitch or return to play, which may help prevent musculoskeletal injuries and time loss from sports participation.

Pitch-Tracking Metrics as a Predictor of Future Shoulder and Elbow Injuries in Major League Baseball Pitchers: A Machine-Learning and Game-Theory Based Analysis.

Understanding interactions between multiple risk factors for shoulder and elbow injuries in Major League Baseball (MLB) pitchers is important to identify potential avenues by which risk can be reduced while minimizing impact on player performance. To apply a novel game theory-based approach to develop a machine-learning model predictive of next-season shoulder and elbow injuries in MLB pitchers and use this model to understand interdependencies and interaction effects between the most important risk factors. Case-control study; Level of evidence, 3. Pitcher demographics, workload measures, pitch-tracking metrics, and injury data between 2017 and 2022 were used to construct a database of MLB pitcher-years, where each item in the database corresponded to a pitcher's information and metrics for that year. An extreme gradient boosting machine-learning model was trained to predict next-season shoulder and elbow injuries utilizing Shapley additive explanation values to quantify feature importance as well as interdependencies and interaction effects between predictive variables. A total of 3808 pitcher-years were included in this analysis; 606 (15.9%) of these involved a shoulder or elbow injury resulting in placement on the MLB injured list. Of the >65 candidate features (including workload, demographic, and pitch-tracking metrics), the most important contributors to predicting shoulder/elbow injury were increased: pitch velocity (all pitch types), utilization of sliders (SLs), fastball (FB) spin rate, FB horizontal movement, and player age. The strongest game theory interaction effects were that higher FB velocity did not alter a younger pitcher's predicted risk of shoulder/elbow injury versus older pitchers, risk of shoulder/elbow injury increased with the number of high-velocity pitches thrown (regardless of pitch type and in an additive fashion), and FB velocity <95 mph (<152.9 kph) demonstrated strong negative interaction effects with higher SL percentage, suggesting that the overall predicted risk of injury for pitchers throwing a high number of SLs could be attenuated by lower FB velocity. Pitch-tracking metrics were substantially more predictive of future injury than player demographics and workload metrics. There were many significant game theory interdependencies of injury risk. Notably, the increased risk of injury that was conferred by throwing with a high velocity was even further magnified if the pitchers were also older, threw a high percentage of SLs, and/or threw a greater number of pitches.

Poster 171: Comparative Analysis of Kinetic Variables Between Different Pitch Types in Professional Baseball Pitchers

Objectives: The persistent high rates of elbow injuries among professional baseball pitchers indicates a critical gap in our understanding of how a pitch influences load on the elbow. Traditionally, research has examined the maximum value of various kinetics experienced at the throwing arm during a pitch, especially elbow varus torque. The maximum elbow varus torque has been used as a surrogate for potential elbow injury; however, the elbow injury epidemic has still persisted. It is possible that analysis focused on only the maximum value misses the total load experienced on the throwing arm. Therefore, the purpose of this study was to investigate different metrics to evaluate elbow stress, including maximum elbow varus torque, elbow loading rate, and cumulative varus torque between different pitch types. By evaluating these aspects of elbow stress, our study aims to uncover previously overlooked kinetic variables that might be potential contributors to elbow injuries, bridging the gap between existing kinetic analyses and the persistent high injury rates. Methods: Data from a cohort of 41 professional baseball pitchers were utilized for this analysis (188 ± 6 cm; 91.9 ± 8.2 kg). Pitchers threw a series of fastball, changeup, and curveball pitches (fastball: 10 ± 3 pitches, changeup: 3 ± 1 pitches, curveball: 4 ± 1 pitches) captured using a 3D motion capture system (480 Hz). Kinetic variables were calculated for each pitch, including maximum elbow varus torque, loading torque rate (measured as the derivative of the varus torque curve), and cumulative elbow varus torque (measured as the area under the elbow varus torque curve). A linear mixed effects model was employed to examine within player associations between pitch type and ball velocity, maximum elbow varus torque, loading torque rate, and cumulative elbow varus torque. Statistical significance was set at p&lt;0.01. Results: Our findings reveal that the fastball pitch created greater loading on the elbow compared to the change up and curveball pitches (Table 1). Pitchers threw their fastball with increased ball velocity (40.3 ± 0.6 m/s) compared to throwing their changeup (36.6 ± 0.5 m/s) and curveball (33.7±0.5 m/s) (p&lt;0.001). Maximum elbow varus torque was also greater in the fastball pitch (93.7 ± 3.3 N∙m) compared to the changeup pitch (84.1 ± 2.4 N∙m) and curveball (91.0 ± 2.3 N∙m) (p&lt;0.001); the curveball pitch had greater maximum torque compared to changeup pitches (p&lt;0.001). The loading rate was 15% lower for the changeup pitch (690.0 ± 49.4 N∙m/s) (p&lt;0.001) and 6% lower for the curveball (753.6 ± 60.3 N∙m/s) compared to the fastball (820.1 ± 72.2 N∙m/s) (p&lt;0.001). The cumulative elbow varus torque for the fastball was 4% greater than the changeup pitch (2996.9 ± 92.9 vs 2894.1 ± 84.1 N∙m) and 7% greater than the curveball pitch (2996.9 ± 92.9 vs 2797.2 ± 85.8 N∙m) (p&lt;0.001). Conclusions: This study reveals the importance of considering pitch type when evaluating kinetic variables in professional baseball pitchers. The observed differences in elbow varus torque, loading rate, and other kinematic metrics between fastball, changeup, and curveball pitches highlights the need for a comprehensive understanding of biomechanical variations associated with different pitch types. These findings have implications for optimizing pitcher training programs, injury prevention strategies, and player management. By unraveling the intricate connections between kinetic variables and pitch types, this research contributes to advancing the biomechanical knowledge within the field of orthopedics and sports science.

Ulnar collateral ligament repair in professional baseball players.

While initial reports of surgical repair of ulnar collateral ligament tears are promising, studies detailing post-repair outcomes are lacking. This study explores the effectiveness of ulnar collateral ligament (UCL) repair in returning professional baseball players to their pre-injury level of play. Our hypothesis is that professional baseball players undergoing UCL repair will have successful outcomes and high return to sport rates after surgery. Publicly available databases were utilized to search for data on professional baseball players who underwent UCL repair from 2016 to 2021. Players undergoing primary UCL repair with an internal brace were included. Amateur players were excluded as were those undergoing revision UCL repair or UCL reconstruction. Of the 11 pitchers who underwent UCL repair, minor league baseball (MiLB) pitchers returned to the sport at an average of 17.5 months. MiLB pitchers had similar earned run averages (ERAs), games played, innings pitched, and walks plus hits per inning pitched ratios (WHIPs) before and after surgery. Four major league baseball (MLB) pitchers (80%) returned to the sport at 9.55 months. MLB pitchers played fewer games and pitched fewer innings than before the surgery, but their ERAs and WHIPs were similar before and after surgery. Pitch velocity and spin rates after surgery varied based on pitch type. The seven positional players who underwent UCL repair showed no differences in batting or fielding performance before and after surgery. UCL repair can successfully return both pitchers and positional players at both the MiLB and MLB levels to play at pre-injury performance levels. Repair can be considered as an option for qualifying injuries in players hoping to maximize performance after surgery with minimal recovery time. Level of Evidence: IV.

Comparison of glenohumeral and scapulothoracic kinematics between fastballs and curveballs during baseball pitching

ABSTRACT Shoulder injuries are common in baseball pitchers and primarily involve the glenohumeral joint. Past analyses have examined shoulder biomechanics during different pitch types simply as the motion of the upper arm relative to the thorax. In this study, glenohumeral and scapulothoracic kinematics were compared between fastballs and curveballs at key timepoints throughout a pitch. Upper extremity kinematics of thirteen collegiate pitchers were collected during fastball and curveball pitches with motion capture. A linear model approach was utilised to estimate scapular kinematics based on measurable humerothoracic motion. Glenohumeral kinematics were computed from the scapular and humeral motion data. Comparisons of scapulothoracic and glenohumeral kinematic variables at times of maximum glenohumeral external rotation, ball release, and maximum glenohumeral internal rotation between pitch types were made using paired t-tests with Benjamini-Hochberg corrections. There were no significant differences in glenohumeral kinematics. Fastballs elicited significantly less scapulothoracic internal rotation and more posterior tilt at maximum glenohumeral external rotation. Fastballs produced significantly less scapulothoracic internal rotation and anterior tilt at maximum glenohumeral internal rotation. This study provides further evidence that risk of injury to the glenohumeral joint may be consistent between fastballs and curveballs and offers insights into subtle differences in scapular kinematics between pitch types.

Classifying batted ball outcomes from Division I collegiate baseball players

ABSTRACT Modern technology challenges anecdotal beliefs on baseball performance. The study’s purpose examines these beliefs by classifying batted ball outcomes. Three categories of independent variables (anthropometry, in-game situation, technique-based), from 1,922 batted ball outcomes produced by 230 players, were used to classify the likelihood of hits during 2021 college baseball games. Anthropometry included player’s heights and weights. In-game situation entailed batter side, same side, ahead count, and pitch type. Technique-based variables measured by TrackMan radar included exit speed (ExSp), launch angle (LA), batted ball distance (BBD), and hang time (HT). Binary logistic regression analysis was performed with batted ball outcome as the dependent variable. Independent variables provided a good fit (χ2 (10) = 522.358, p < 0.01) and correctly classified nearly three-fourths of outcomes. Height (β = 0.030, p < 0.05), ExSp (β = 0.023, p < 0.05), LA (β = 0.028, p < 0.01), and BBD (β = 0.067, p < 0.01) each had significant positive associations, yet HT (β = –1.661, p < 0.01) had a significant negative association, with batted ball outcomes. TrackMan provided four significant independent variables. Anthropometry’s contribution to batting outcome was modest, while in-game situation’s impact was non-significant; results contradict anecdotal beliefs of their importance.

Changing It Up: Determining the Nash Equilibria for Major League Baseball Pitchers

In order to prevent batters from hitting a pitch, pitchers must decide on a strategic balance of many different pitch types. While each pitcher has preferred pitches (likely those with which he is most confident), he cannot over-utilize his dominant pitches, or batters will be able to gain a strategic advantage in trying to put the ball into play. We analyze Major League Baseball (MLB) pitch data from 2008 to 2018 in order to determine whether or not MLB pitchers are able to reach the theorized mixed-strategy Nash equilibrium given the pitcher’s skill in utilizing each type of pitch. Our data suggests that MLB pitchers are in fact rational, and succeed in reaching the mixed-strategy Nash Equilibrium.

Assessing the validity and reliability of a baseball pitch discrimination online task

ABSTRACT There has been an increasing interest in training perceptual skills in sports through online video-based methods, particularly in baseball. However, there is little empirical evidence related to the reliability and validity of such online methods for the assessment of these skill. Here we developed an online task to assess pitch discrimination and evaluated (a) inter-item reliability, (b) reliability in assessment compared to an in-person task, also tapping into external validity and (c) discriminability across different skill groups. We also compared performance on a non-sport specific Dynamic Visual Acuity task (DVA), thought to tap into underlying visual skills comprising pitch discrimination. Skilled, Varsity-level baseball players (n = 17) were compared to novices (n = 14) when discriminating pitches thrown by two different pitchers, across three pitch types, edited to progressively remove sections of ball flight (3 time points). The online task discriminated across skill groups, showed good reliability across repeated viewings and from the online task to an in-person assessment of skilled athletes (n = 8). There were, however, differences in reliability and discriminant validity based on the type of pitcher, with one pitcher being responded to more accurately and reliably. Skilled participants showed good discriminability between fastballs and change-ups. There were no group differences for DVA, nor did it correlate with pitch discrimination for the skilled group. These data illustrate the reliability of online video assessments, but raise issues concerning discriminability across different pitchers and when standing ready to swing. Greater sensitivity testing of such assessments is still needed, within and across skill groups.

Effect of pitch crystallinity on electrochemical performance of graphite carbon coatings

Natural graphite has been primarily used as an active anode material for lithium-ion batteries, and carbon coatings are commonly used to enhance its performance. Pitch has been proposed as a promising material for carbon coatings, but it comprises various chemical species and cannot be regarded as a single substance. Consequently, different types of pitch variably alter the electrochemical properties of the graphite carbon coating. In this study, we focus on the relationship between the crystallinity and electrochemical performance of the carbon coating layer, which is formed based on the optical properties of pitch and can be categorized as isotropic or mesophase. To apply the pitch onto the natural graphite, a dry coating method was employed and it was then heat-treated with a temperature range of 900–1700 °C. Both carbon coatings enhanced the initial Coulombic efficiency by reducing the edge plane of natural graphite. In particular, the carbon layer coated with an isotropic pitch exhibited a disordered structure, thereby improving the output characteristics. The synergistic effect of the conductivity of the carbon coating layer and the amorphous arrangement of the carbon crystals provided a pathway for ion diffusion, effectively reducing the polarization resistance that arose during the charge and discharge cycles. This report establishes a connection between graphite-coated carbon layers and electrochemical performance and provides a novel evaluation of the properties of coating pitches that are in high demand for commercial applications.

The Impact of Screw Pitch Types on Screw Feeder Performance on Floating Fish Feed Machine

One of the important parts of the floating pellet machine, a tool often used in Indonesia to produce fish feed, is the screw press. The largest contributor to the overall production cost in fish farming is fish feed. Floating pellet machines usually require two motors and have large machine dimensions due to the use of two constant-pitch screw feeders. The purpose of this study was to optimize the performance of the floating fish feed machine with one screw press and one drive motor, with the screw feeder selected as the variable-pitch type. The simulation method was used to compare the mass flow rate produced by each screw pitch and the pressure value parameters on the screw. Based on the results of the study, by using the same fish feed machine base, changing the screw pitch type from the constant type to the variable type, provides an increase in the quality of the fish feed produced to be denser and not easily destroyed, and its buoyancy increases.

Effects of Increasing Pitch Count on Pitch Type Ball Metrics and Release Height in High School Softball Pitchers.

Softball research has investigated changes in physical characteristics, mechanics, and ball speed as elements of fatigue. However, the influence of pitch volume on ball metrics is unclear. The purpose of this study was to investigate the influence of pitch volume on ball performance and release metrics in softball pitchers across different pitch types. As pitch volume increased, there would be a decrease in ball metrics of the fastball and changes in breaking pitches would be observed earlier than the fastball or changeup. Descriptive laboratory study. Level 5. A total of 21 (15.4 ± 1.6 years; 1.6 ± 0.2 m; 76.0 ± 17.2 kg) softball pitchers participated. Procedures consisted of participants pitching a simulated game consisting of 100 pitches, taking a 30-minute break, and then throwing 12 pitches to simulate the first inning of a doubleheader. Participants randomly threw each pitch type (fastball, changeup, curveball, or dropball). Ball performance and release metrics were measured using a Rapsodo portable pitch tracker. A 3 (time) by 4 (pitch type) multivariate analysis of variance revealed that pitch speed was significantly higher in the first inning compared with the last inning and the doubleheader inning. The fastball, curveball, and dropball revealed a significant difference in pitch speed between timepoints. Specifically, the curveball and dropball first-inning pitch speed was significantly greater than the last and doubleheader inning. Alternatively, the fastball had a significant increase in pitch speed from the last inning to the doubleheader inning. The typical 30-minute break given between games for doubleheaders may be sufficient recovery time for the fastball but not for the curveball and dropball. The Rapsodo device is an accessible method of tracking ball performance and pitch release metrics and could be helpful in identifying when a pitcher may be experiencing performance detriments in response to increasing pitch count.

A Retrospective Analysis of Major League Baseball Hit-by-Pitch Rates before and after the Crackdown on Foreign Substance Use.

Determine whether there was an increased incidence of hit-by-pitch events in Major League Baseball (MLB) following the decision to enforce the foreign substance ban for pitchers during the 2021 season. Descriptive Epidemiological Study. Major League Baseball hit-by-pitch data from publicly available Web sites ( mlb.com and fangraphs.com ). Major League Baseball players during the 2017, 2018, 2019, 2021, and 2022 seasons. Hit-by-pitch exposure data by season and individual pitch type. Hit-by-pitch incidence rates from the 2017 to 2019 seasons (preenforcement) and the 2021 to 2022 seasons (postenforcement). Rates were compared with incidence rate ratios (IRRs). Hit-by-pitch incidence rate increased from 2.66 to 3.06 per 1000 total pitches (IRR, 1.15 [95% CI, 1.08-1.23]; P < 0.0001) following the enforcement. Incidence rates for 2017, 2018, and 2019 did not differ from each other individually, but incidence rate of all 3 seasons individually were significantly lower than that for the 2021 season ( P < 0.005). Sliders were 29% more likely to hit batters following the enforcement ( P = 0.0015). Major League Baseball batters were hit by pitches at a significantly higher rate following the league's crackdown on foreign substance use for the 2021 seasons compared with the same time of year during the 2017 to 2019 seasons. This was followed by a slight regression toward preenforcement levels during the 2022 season.

Machine Learning Approach for Pitch Type Classification Based on Pelvis and Trunk Kinematics Captured with Wearable Sensors

Machine Learning Approach for Pitch Type Classification Based on Pelvis and Trunk Kinematics Captured with Wearable Sensors

Addressing Challenges in Dual Sided SiP Thermal Budget

System-in-Package (SiP) has been adopted as the mainstream advanced packaging technology in many consumer applications including 5G smartphones, tablets, wireless earbuds, smart wearables, etc. Heterogeneous integration, smaller form factor, better electrical performance, lower cost of assembly and faster time to market are the key differentiators of SiP as compared to conventional packaging techniques. In applications such as 5G mobile RF Front-End (RFFE) and Antenna-in-package (AiP) modules, dual sided SiP is the popular approach which brings even higher level of integration and smaller form factor. However thermal warpage control is a significant challenge during two times of solder reflow processes for the front and back sides of the package, especially if one side is with underfill and mold materials which have significant CTE mismatch to the substrate and dies, causing delamination failures and yield losses. This study examines the novel solution of reducing thermal budget with the use of a low temperature solder paste material based on SnBiAg alloy in ultra-fine pitch Type 6 solder powders. It allows a minimal peak reflow temperature of only 170 °C that effectively reduces warpage of dual sided SiP substrates. Solder alloy and paste properties and solder joint microstructures are examined in detail for tests including fine-pitch printing and component soldering, thermal aging test on different substrate finishes, thermal cycling test and mechanical drop test for reliability performance.

Numerical Analysis of The Effects of Propeller High Thrust Distribution on Propulsion System Performance

High ship propulsion performance is the main goal of designers, propeller is one component of the propulsion system that also affects the performance of the propulsion. In propeller planning, it is necessary to pay attention to the efficiency of the propeller, in addition to reducing ship operating costs and reducing CO2 gas emissions which is one of the requirements for ships built above 2013, the rules have been made into the Energy Efficiency Design Index (EEDI) standard. At this time the propeller that is widely used is the B Series propeller including the propeller design used on mini LNG ships, namely the B6.40 propeller, the B Series propeller has a pitch character from the Wageningen Propeller Series study. Innovations are made to get better propeller efficiency by varying the pitch distribution. The B6.40 propeller of the standard constant pitch type was modified to B6.40 variable pitch (high thrust). Propellers with high thrust have better efficiency especially for non-fast boats. This study was conducted to obtain the best propeller efficiency of a constant pitch propeller and three high thrust propeller units using Numeca's Computational Fluid Dynamics (CFD) numerical self-propulsion test. For validation of the simulation program by comparing the results of the open water test B6.40 Wageningen while resistance validation by comparing the ship resistance model test. The results of the self-propulsion test using Disc Actuator show that the propulsion coefficient (PC) of Modified-2 and Modified-3 high thrust propellers is better when compared to constant pitch. The magnitude of the increase in PC value reaches ± 4% higher than the constant pitch type on the Modified-3 propeller.

Pitch release speed predictors for division I collegiate baseball players

BACKGROUND: Analytics, to quantify baseball pitch metrics, take on many forms and are unlike earlier methods to assess performance. OBJECTIVE: Quantify associations of flight kinematic and anthropometric variables on pitch release speed. METHODS: Male college-age pitchers (n= 182) from 2021 Division I games provided data. A 3D radar system collected data. Fixed effects regression OLS models analyzed data for sliders, changeups, curveballs, and fastballs. RESULTS: Spin rate (r= 0.017–0.514, p&lt; 0.05) and vertical break (r= 0.374–0.703, p&lt; 0.05) were positively associated with pitch release speed per pitch type. Release height (r=-0.286–0.051, p&lt;-0.05) and pitch extension (r=-0.176–0.43, p&lt; 0.05) were negatively associated with pitch release speed per pitch type except sliders. Spin axis had a negative association with pitch release speed for fastballs (r=-0.235, p&lt; 0.05) and sliders (r=-0.311, p&lt; 0.05), and a positive association (r= 0.029, p&lt; 0.05) with curveball pitch release speed. Weight only related to pitch release speed for fastballs (r=-0.315, p&lt; 0.05). Height did not impact pitch release speed. CONCLUSIONS: Results refute long-held beliefs of anthropometry’s influence on performance and instead reveal flight kinematics’ impact on baseball pitch release speed.

Timing Of Peak Shoulder Distraction Force Between Pitch Types Across A Simulated Softball Game

Timing Of Peak Shoulder Distraction Force Between Pitch Types Across A Simulated Softball Game

A novel method intersecting three-dimensional motion capture and medial elbow strength dynamometry to assess elbow injury risk in baseball pitchers

In baseball pitching, resultant elbow varus torque reaches the peak value of 50–120 N m, exceeding the joint failure limit that risks damage to the ulnar collateral ligament (UCL). In-vivo methodology is lacking to assess whether pitchers have sufficient muscular strength to shield UCL and how strongly the elbow musculature must contract to minimize valgus loading on UCL. This study introduces a method to assess relative percentages of muscular varus strength required to unload the UCL. The maximum voluntary isometric varus strength (MVIVS) produced by the medial elbow musculature and the maximum resultant varus torques at elbow in pitching fastballs and other types were measured for two professional pitchers. Simulation was conducted to determine the relative percentages of MVIVS required to unload the UCL to varying degrees and the impact of athletes’ previous UCL reconstruction on the relative percentages was examined. The maximum resultant varus torque in pitching was found to range 72–97%MVIVS depending on the type of pitch. The elbow musculature had to produce 21–49%MVIVS to avoid acute failure of intact UCL whereas the corresponding requirements were 39–63%MVIVS for UCL reconstructed joint. The method offers new insight into baseball pitcher’s training/rehabilitation and physical assessment to reduce the risk of UCL injury.