Speed Pitch Research Articles

The effect of Dynamic tape’s directional support on shoulder fatigue and pitching performance in amateur baseball players: a randomized crossover trial

BackgroundTo evaluate whether the application of Dynamic tape to the pitching shoulder could result in reduced shoulder fatigue, reduced delayed onset muscle soreness, or improved performance.MethodsThis is a randomized crossover study, in which participants and investigators were blinded, included 20 amateur adult baseball players without shoulder pain. Sham taping and Dynamic taping were randomized, using an internal rotation support taping method in both groups. Bilateral shoulder strength and range of motion were measured with a handheld dynamometer and clinical goniometer before and after each test. The percentage of strength decrease, range of motion, pitch velocity, spin rate, and shoulder pain were recorded. The post-pitching decrease in strength and percentage of strength decrease were calculated by paired t-test and the pitching speed and spin rates in the innings for both the sham and Dynamic taping groups were analyzed using two-way ANOVA.ResultsCompared with the sham group, the Dynamic tape group showed a significant loss in the percentage of strength decrease in internal rotation compared to the sham group (-1.4% vs. 7.0%, p = 0.03). However, no significant differences were observed in other strength declines, shoulder range of motion, pain, pitching velocity, or spin rate.ConclusionsDynamic tape reduced direction-specific shoulder fatigue but did not significantly enhance pitching performance or prevent delayed onset muscle soreness.Trial registrationClinicalTrials: N201912094.

Ongoing confirmation of an objective criterion predicting annoyance linked to wind turbines

The 2023 CAA Acoustics Week in Canada introduced a criterion based on an objective acoustic measure to predict annoyance subjectively identified by residents living in the vicinity of wind turbines. That evidence was gathered primarily at a site near constant speed, stall regulated wind turbines. This paper presents subsequent investigations confirming that the criterion is also effective at a site with variable speed pitch regulated wind turbines. The results arise from the analysis of over 400 days of sampling at a site 787 m from the nearest wind turbine, with 18 turbines within 3 km. Verification of the study data was shown by comparison to data collected by an acoustic contractor employed by the provincial Ministry of the Environment. That data was collected through over 70 recording periods to analyze times residents at the site identified annoyance during a Ministry audit. These samples were obtained through a Freedom of Information request purchase. Analysis of the samples confirms the annoyance criterion identified at the CAA 2023 conference applies also for a different turbine type to objectively predict the annoyance subjectively identified by residents. The implications of this confirmation will be discussed.

Predictors of batting and pitching performance in the USA baseball prospect development pipeline

ABSTRACT This study examined the relationship between psychomotor abilities and baseball performance by analysing data from 379 athletes who participated in the USA Baseball, Prospect Development Pipeline (PDP). Hit and pitch metrics were generated during practice sessions using the RapsodoTM System. Data were compared through exploratory factor analysis and hierarchical regression. Factor analysis grouped batter’s PDP evaluations into four latent variables accounting for 63% of variance. Pitcher performance grouped into three factors accounting for 51% of variance. Regression on batter data revealed a significant demographic/anthropometric base model with height, weight, and age that accounted for 58% of the batted ball speed (R2 = 0.581). Player position explained 2% of the variance (R2 = 0.604), and PDP evaluation scores contributed an additional 3% (R2 = 0.631). Regression of pitcher data showed a significant base demographic/anthropometric model accounting for 36% of fastball pitch speeds (R2 = 0.363), with the PDP evaluation scores adding 6% additional variance (R2 = 0.424). Uniformly, assessments of lower body strength added the greatest predictive information. Hand grip strength did not correlate with pitch metrics. While demographics/anthropometrics are major contributors to batted and pitched ball speed, position and psychomotor variables add statistically significant contributions and may be of practical value for player selection.

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.

Kinematic Parameters Predictive of Pitch Velocity in Youth to Professional Baseball Pitchers: A Qualitative Systematic Review.

Specific kinematic factors have been found to contribute to faster pitch speeds, with poor mechanics leading to injury. To discuss the kinematic parameters that predict faster ball velocity among baseball pitchers. Systematic review. Using the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, the authors utilized the Cochrane Database of Systematic Reviews, PubMed (2008-2019), and OVID/MEDLINE (2008-2019) databases. Eligible articles included those that reported on kinematic factors predictive of ball velocity across youth, high school, collegiate, and professional levels of play. The quality of all included studies was evaluated by 2 reviewers using the Appraisal tool for Cross-Sectional Studies (AXIS). The lack of consistent study design or outcome variables precluded meta-analysis. A total of 584 studies were identified from the initial search with 12 included in final analysis (930 pitchers in total; 429 [46.1%] youth, 164 [17.6%] high school, 153 [16.5%] collegiate and 184 [19.8%] professional) with mean ball velocity of 71.1 mph (114.4 km/h). The average AXIS score was 16 out of a possible 20. The shoulder played a significant role in the generation of velocity-induced torques. Hip and shoulder separation was associated with a 2.6 ± 0.5 mph (4.1 ± 0.8 km/h) increase in velocity, whereas increased shoulder movement of the nonthrowing arm was negatively correlated with initial ball velocity (r2 = 0.798). Furthermore, hip/shoulder separation, decreased movement of the nonthrowing shoulder, trunk power and timing of maximum trunk rotation, increased contralateral trunk tilt and increased sagittal-plane trunk tilt, and decreased knee flexion at ball release were all associated with higher fastball speeds. Multiple upper extremity and trunk kinematic parameters affect ball velocity, with significant contributions from the throwing shoulder and trunk, as well as nondominant arm. Understanding kinematic predictors of faster ball velocity can help guide training regimens.

고등학교 야구 투수의 전문 체력요인이 투구속도에 미치는 영향: 예비연구

This study was conducted to provide basic data for pitcher training and physical strength training by analyzing the effect of high school baseball pitcher’s professional fitness factors on throwing velocity. The subjects of the study were high school baseball pitchers(n=10) and evaluated using the Baseball Athletic Test(BAT). BAT was a field test for baseball pitchers and analyzed body composition, flexibility, muscular strength, leg power, agility, running speed, and throwing velocity, and the following results were derived. First, body composition(height, weight, body fat percentage, muscle mass) did not show a significant correlation with throwing velocity. Second, grip strength showed a significant correlation with pitching speed improvement(R²=.683, p＜.05) Third, vertical jump showed a significant correlation with throwing velocity(R²=.754, p＜.05). Fourth, 60yd sprint was found to have a statistically significant correlation with throwing velocity((R²=-.766, p＜.01). To summarize the above, baseball pitchers showed significant correlations with vertical jump, grip strength, and 60yd sprint. Therefore, leg power, grip strength, and running speed among professional physical fitness factors are judged to be important factors in improving pitcher’s throwing velocity, and are judged to be effective basic data for analyzing and training pitchers’ physical strength in the future.

Linear Parameter Varying Power Regulation of Variable Speed Pitch Manipulated Wind Turbine in the Full Load Regime

In a wind energy conversion system (WECS), changing the pitch angle of the wind turbine blades is a typical practice to regulate the electrical power generation in the full-load regime. Due to the turbulent nature of the wind and the large variations of the mean wind speed during the day, the rotary elements of the WECS are subjected to significant mechanical stresses and fatigue, resulting in conceivably mechanical failures and higher maintenance costs. Consequently, it is imperative to design a control system capable of handling continuous wind changes. In this work, Linear Parameter Varying (LPV) H∞ controller is used to cope with wind variations and turbulent winds with a turbulence intensity greater than ± 10%. The proposed controller is designed to regulate the rotational rotor speed and generator torque, thus, regulating the output power via pitch angle manipulations. In addition, a PI-Fuzzy control system is designed to be compared with the proposed control system. The closed-loop simulations of both controllers established the robustness and stability of the suggested LPV controller under large wind velocity variations, with minute power fluctuations compared to the PI-Fuzzy controller. The results show that in the presence of turbulent wind speed variations, the proposed LPV controller achieves improved transient and steady-state performance along with reduced mechanical loads in the above-rated wind speed region.

Design Loads in Small Wind Turbines: a Detailed Comparison Between Pitch and Stall Regulation

Small wind turbines (SWTs) have known alternate fortune but can now play a key role in distributed production to foster energy transition. Among the typical features of small machines, the use of stall regulation is a distinctive one, since the ubiquitous variable speed pitch regulation used in utility-scale rotors is hampered by space constraints in small nacelles. This reduced the cost and boosts overall reliability; on the other hand, compromises in the aerodynamic design of the blades must be adopted to ensure smooth power regulation above rated windspeed. This has implications not only on the final Annual Energy Production (AEP) of the rotors, but also on loads. The current study aims at investigating the differences in peak loads between a stall and a pitch regulated SWT. The UNIFI 50kW SRWT, a reference turbine designed by Università degli Studi di Firenze, is used as a case study thanks to the fact that is available both with stall and pitch control options. Differently from most of the studies to date, simulations are carried out for a variety of power production and parked load cases, significant for extreme loading of the rotor and tower of the wind turbine, thus strongly impacting on the design. Results demonstrate how a pitch-regulated machine can ensure a significant reduction of the main maximum loads, thus paving the way for more optimized and cost-effective designs of future SWTs.

Clinical shoulder measurements related to joint loads in collegiate pitchers

Pitchers are prone to upper extremity injury due to repetitive high joint loads. Clinical measures of shoulder strength and range of motion (ROM) have shown links to injury risk in pitchers, however, these factors have rarely been studied in relation to throwing joint loads. The purpose of this study was to identify which clinical ROM and isokinetic strength variables were related to peak shoulder and elbow joint torques in collegiate pitchers. Thirty-three healthy collegiate pitchers participated in this study. Fastball velocity, shoulder concentric and eccentric strength, and passive shoulder ROM variables were analyzed using a Lasso regression to determine what factors influenced shoulder internal rotation torque and elbow varus torque. Fastball velocity was selected by the Lasso as indicator of increased shoulder and elbow torque. Passive shoulder external rotation ROM was also selected as an important factor in joint loading with increased shoulder external rotation ROM being related to lower joint loads. The bilateral ratio of shoulder internal rotator concentric strength was related to peak shoulder and elbow torques with an increase in the bilateral ratio of shoulder strength leading to reduced joint torques. Increases in the eccentric external rotator to concentric internal rotator strength (functional ratio) of the dominant arm and increases in dominant arm eccentric internal rotator strength were both related to increases in each joint torque. Results from the study indicate that pitch speed, passive shoulder external rotation ROM, and the isokinetic shoulder strength profile including internal rotator strength and functional strength ratio of pitchers are related to joint loading during the pitch and may be important to monitor in relation to injury risk and/or during rehabilitation. These results provide insight into the role that both shoulder ROM and rotator cuff strength play in the dynamic stabilization of the elbow and shoulder during pitching.

A Dual-Position Loop LLADRC Control Method Based on Harmonic Gear Drive

High-resolution imaging has become a development trend and is widely used in military and civil fields. As the carrying equipment of imaging system, the speed stability of tracking turntable is the basis of high-resolution and stable imaging. At present, in the aerospace field, there are high requirements for peak power dissipation and holding torque, so flexible joints such as harmonic gear drive are mostly used to realize the function. The characteristics of flexible load have a great impact on the characteristics of motion control, which is easy to cause mechanical resonance, lead to system instability, and have a great impact on speed stability and position tracking accuracy. Therefore, it is necessary to study the servo system of flexible load. In order to solve the problems of high-precision position control and speed stability at low speed of flexible turntable with uncertain load, on the one hand, we comprehensively consider the advantages and disadvantages of semi-closed-loop and full closed-loop control and design a dual-position loop feedback control system combined with the analysis of dynamic equation to realize speed stability and high-precision position control. On the other hand, according to the requirements of the speed stability at low speed of the turntable, the tracking differentiator (TD) is designed innovatively through the language three-point interpolation subdivision and five-point pre-deduction calculation method. Finally, a dual-position loop LLADRC (language linear active disturbances rejection controller) control method based on harmonic gear drive is studied. By comparing the semi-closed loop, dual-position loop, dual-position loop LADRC (linear active disturbances rejection controller, ADRC), and dual-position loop LLADRC methods through simulation analysis, it can be shown that the double position LLADRC control method is obviously superior to other schemes in terms of rapidity, speed stability at low speed, and position tracking accuracy. The theoretical research is verified by experimental test. When the given speed is 0.1 ° / s , taking the pitch axis as an example, the pitch speed error is 0.0039 ° / s (3σ). When the maximum speed of the given curve is 20 ° / s and the maximum acceleration is 16 ° / s , the position tracking error is 0.0025° (3σ). This control method solves the problems of system instability and low-speed stability in high-precision control of turntable system based on harmonic gear drive and provides a method for high-precision control of high-resolution imaging turntable.

Softball Pitching Propulsion and Performance Differences According to Body Fat Percentage.

Softball pitchers with a high body-fat percentage (bf%) can often be successful, despite the heightened risk of injury associated with high bf%. Given the importance of propulsion during pitching, those with high bf% may have an advantage performance-wise. Therefore, the purpose of this study was to examine the differences in ground reaction force (GRF) development between two groups of pitchers: those with a high-fat percentage (≥32 bf%) and a healthy-fat percentage (<32 bf%). Thirty-two female high-school softball pitchers (1.70±.06 m, 76.09±17.50 kg, 15±1 yrs) completed dual-energy x-ray absorptiometry (DEXA) scans. GRF data were collected during pitch propulsion via a force plate, pitch speed was captured using a radar gun, BMI was calculated from pitcher height and mass, and fat free mass index (FFMI) and fat mass index (FMI) were calculated using DEXA data and pitcher height. Multivariate analysis of variance revealed pitcher group GRFs differed significantly (F3,30=3.45, p=.030). Univariate follow-up analyses showed healthy bf% pitchers presented greater weight-normalized peak medial GRF (F1,30=7.17, p=.012). BMI and FFMI were positively associated with pitch speed while bf% and FMI were negatively associated with pitch speed. While pitchers can be successful and carry excess bf%, results indicate potential performance disadvantages associated with having an increased bf%.

Steady State Modeling and Performance Analysis of a Wind Turbine-Based Doubly Fed Induction Generator System with Rotor Control

The utilization of renewable energy sources aids in the economic development of a country. Among the various renewable energy sources, wind energy is more effective for electricity production. The doubly fed induction generator is an extensively known wind turbine generator for its partially rated power converters and dynamic performance. The doubly fed induction generator assists the wind turbine to function with a wide speed range. Hence, the steady-state performance analysis of a doubly fed induction generator helps enable it to operate efficiently at a specific wind turbine speed. In this paper, a 2 MW variable speed pitch regulated doubly fed induction generator with a speed range of 900—2000 rpm was opted for steady-state analysis. This was followed by the design and modelling of a doubly fed induction generator in Matlab/Simulink environment, and the analyses were performed using mathematical equations computed via Matlab coding. The steady-state magnitudes were calculated with rotor magnetization idr = 0. The closed-loop stator flux-oriented vector control is applied to the rotor side converter for controlling the designed doubly fed induction generator model. The simulation results were compared with computational values to establish a workable model with less than 10% error. The simulation model can be used for predicting the performance of the machine, fault analysis, and validation of existing DFIG at a steady state.

Decreased Shoulder and Elbow Joint Loads During the Changeup Compared With the Fastball and Curveball in NCAA Division I Collegiate Softball Pitchers.

Background:Baseball leagues have implemented pitch count and pitch type restrictions based on biomechanical concepts associated with pitch type. Softball has not yet adopted these practices, although softball pitchers continue to pitch at a high volume and learn multiple pitches at a young age.Purpose:To examine shoulder and elbow kinetics between the fastball, curveball, and changeup, as well as to provide descriptive upper extremity pain data in National Collegiate Athletic Association (NCAA) softball pitchers.Study Design:Descriptive laboratory study.Methods:Study participants consisted of 27 female NCAA Division I softball pitchers (age, 20.2 ± 1.9 years; height, 175.7 ± 5.7 cm; weight, 83.6 ± 12.7 kg). The participants pitched 3 balls of each pitch type, and kinetic data were recorded. A one-way within-participants repeated-measures multivariate analysis of variance was used to determine significant differences in kinetics and pitch speed between pitch types.Results:Results revealed a statistically significant main effect for pitch type (Wilks λ = .087; F = 36.523; P < .001). Post hoc testing showed that the changeup produced less anterior elbow force compared with the fastball (P < .001) and the curveball (P = .012). In addition, the changeup produced less shoulder distraction force compared with the fastball (P < .001) and the curveball (P = .001). Additionally, there was a significant difference in pitch speed between all 3 pitch types (P = .006). The curveball revealed no statistically significant kinetic differences compared with the fastball.Conclusion:The fastball and curveball placed similar stress on the upper extremity in collegiate softball pitchers. However, in comparison with the changeup, the fastball and curveball placed increased stress on the upper extremity. More research is needed to fully explain the differences seen between pitch type and injury risk.Clinical Relevance:Sports medicine professionals, coaches, and athletes should use the current study results to note these differences in shoulder distraction and elbow anterior forces between softball pitch types. The study results can be used as a reference and basis for future research investigating kinetic differences across varying pitch types.

Analysis of the Lower Limb Muscles' Function for the Prevention of KNEE JOINT INJURIES of the Intramural Baseball Pitchers of Colleges and Universities

Purpose: The purpose of this analysis is to provide the basic data for the prevention of knee joint damages by analyzing differences in the isokinetic muscular function of knee joints as per the pitching speed of 21 intramu-ral baseball players of colleges and universities. Method: The subjects of this study were 21 intramural baseball players of colleges and universities, whose length of experiences were 2 to 7 years. By measuring the pitching speed, they were classified as S1 group whose maximum ball speed was 110km/h or greater, S2 group whose maximum ball speed was less than 110km/h to 100km/h or greater, and S3 group whose maximum ball speed was less than 100km/h, respectively. The isokinetic muscular strength of knee joints was measured for all of the 3 groups, and the strength of the left and right flexors and extensors were measured at 60°, 180°, and 240°, respectively. The data processing for this study was performed by using the SPSS 18.0 statistical program to calculate the mean and standard deviation for each of the items, and the one-way ANOVA was performed to compare the differences for each item by group, while using the Tukey method as an ex post analysis between the groups. Furthermore, the multiple linear regression was performed to identify the influence of the isokinetic muscular function of knee joints according to the angular speed on the pitching speed. The statistical significance level was set to p<.05, respec-tively. Results: The results of measuring the isokinetic muscular strength of knee joints are as follows. As for the PT and WPR measured at an angular speed of 60°, the S1 group turned out to be significantly higher(p<.05) in the left flexors and extensors than S3 group. As for the PT and WPR measured at an angular speed of 180°, the S1 and S2 groups turned out to be significantly higher(p<.05) in the left extensors than the S3 group. As for the PT measured at an angular speed of 240°, S1 and S2 groups in the left extensor turned out to be significantly high-er(p<.05) than S3 group. As for the WPR, S1 group turned out to be significantly(p<.05) higher than S3 group. The results of performing the multiple linear regression are as follows with a view to discover the effect of iso-kinetic muscular strength of knee joints on the pitching speed. At the angular speeds of 180° and 240°, the regression segments of the left knee joint extensors for both the PT and WPR turned out to have a significant ef-fect at the 5% level. R2, which is the explanatory power of the regression model which explains changes in the pitching speed for the left knee joint extensors, turned out to have an explanatory power in the range of 37.9-55.5%, respectively. Conclusion: Gathering the results above, it turned out that the higher the pitching speed for the group, the superior the muscular function, and in particular, the extensors on the left side demonstrated such remarkably pronounced characteristics. Such results suggest that the extensor muscles could influence the pitching speed for the stretching motion(acceleration) of the left legs during the pitching. Furthermore, in order to prevent injuries, attention ought to be paid to strengthening the counter muscular of the muscles which are primarily used.

Energy generation, absorption, and transfer at the shoulder and elbow in youth baseball pitchers

ABSTRACT Performance during the baseball pitch is dependent on the flow of mechanical energy through the kinetic chain. Little is known about energy flow during the pitching motion and it is not known whether patterns of energy flow are related to pitching performance and injury risk. Therefore, the purpose of this study was to quantify energy generation, absorption, and transfer across the shoulder and elbow during the baseball pitch and explore the associations between these energetic measures, pitch speed, and traditional measures of upper extremity joint loading. The kinematics of 40 youth baseball pitchers were measured in a controlled laboratory setting. Energy flow between the thorax, humerus, and forearm was calculated using a segmental power analysis. Regression analyses revealed that pitch speed was best predicted by arm cocking phase shoulder energy transfer to the humerus and peak elbow valgus torque was best predicted by arm acceleration-phase elbow energy transfer to the forearm. Additionally, energy transfer across the shoulder and elbow generally exhibited the strongest correlations to pitch speed and upper extremity joint loads. These data reinforce the importance of energy transfer through the kinetic chain for producing high pitch speeds and provide descriptive data for energy flow during baseball pitching not previously found in the literature.

Drive leg ground reaction forces and rate of force development over consecutive windmill softball pitches.

Windmill softball pitching is a highly skilled movement, combining whole body coordination with explosive force. Successful pitching requires sequential movement to transfer energy produced by the lower extremity to the pitching arm. Therefore, drive leg ground reaction force (GRF) and the time over which a pitcher can develop force during push off, defined as rate of force development (RFD), is essential for optimal performance. The aim of this study was to examine GRF and RFD in the drive leg during the windmill softball pitch, as well as pitch velocity, throughout a simulated game. Fourteen softball pitchers (17.9±2.3 years, 166.4±8.7cm, 72.2±12.6kg) pitched a simulated game. Pitch velocity and anterior-posterior and vertical GRF and RFD, each normalized to body weight, were collected for each inning. Average pitch speed remained consistent across all seven innings, 49.57±0.42mph. Changes in GRF and RFD were assessed, with level of significance set as P<0.05. A one-way repeated measures analysis of variance showed no significant differences in apGRF%BW (P=0.297), vGRF%BW (P=0.574), apRFD (BW/s) (P=0.085) and vRFD (BW/s) (P=0.059). Training programs can be improved with the knowledge of the magnitude and rate in which forces are developed by the drive leg during push-off of the windmill softball pitch.

Influence of pitch size and goalkeepers on external and internal load during small-sided games in amateur soccer players

PurposeTo analyse the influence of goalkeepers during 4-a-side small-sided games, played in pitches of two different sizes (small: 30 × 20 m, large: 40 × 30 m).MethodsTotal distance covered (TD), distance covered at low- (LSD), moderate- (MSD), high- (HSD) and very high-speed (VHSD), average and maximal speed, Edwards’ training load (Edw-TL), time spent above 90% of maximal heart rate (T90%) and rate of perceived exertion (RPE) were monitored, in 18 amateur soccer players.ResultsHigher TD (mean difference: + 181 m, Hedge’s g: 0.93 and + 400 m, 3.37), MSD (+ 85 m, 0.79 and + 146 m, 1.64), HSD (+ 101 m, 1.41 and + 179 m, 3.26), VHSD (+ 30 m, 1.89 and + 35 m, 1.26), average speed (+ 0.65 km h−1, 0.88 and + 1.47 km h−1, 3.31) and maximal speed (+ 3.60 km h−1, 1.40 and + 3.58 km h−1, 1.40) were found in large than small pitch, without and with goalkeepers, respectively. Goalkeeper’s presence increased Edw-TL (+ 8.4 AU, 0.70) and reduced TD (− 141 m, 0.75), HSD (− 54 m, 0.75) and average speed (− 0.54 km h−1, 0.76) in small pitch and maximal speed (1.59 km h−1, 0.60 and 1.61 km h−1, 0.66) in both small and large pitches, respectively. RPE was higher (+ 20, 1.52) in the large than small pitch when the goalkeepers were present.ConclusionImplementing small-sided games, coaches should be aware that lower external load with similar internal load could be provided using small pitch with goalkeeper rather than either small goals or larger pitch. Furthermore, large small-sided games without goalkeeper may be the best choice for eliciting high training load.

ANALYSIS OF TRUNK POWER AND JOINT STRESSES BETWEEN PROFESSIONAL AND COLLEGIATE PITCHERS

The dynamic motion of a baseball pitch generates high elbow and shoulder torques that can result in injury. Previous research has noted the importance of properly transferring energy from the lower extremities through the throwing arm to decrease joint stress. The goal of this study was to compare segmental powers between two levels of pitchers at various moments throughout the pitching cycle and observe their influence on upper extremity torques. Thirteen professional and thirteen collegiate pitchers participated in this study. Forty-seven reflective markers were attached to the subjects at specific landmarks. An 8-camera motion analysis system was set up surrounding an artificial pitching mound, where participants threw 10 fastballs. Data were exported and processed using Visual 3D software. Welch’s T-tests compared the means between groups with a significance set at p &lt; 0.05. Professional pitchers were found to have significantly greater torso power at foot contact, maximum shoulder external rotation, ball release, and overall peak torso power. They also demonstrated significantly greater pitch velocity. Professional pitchers generated similar elbow varus torque and shoulder internal rotation torque compared to collegiate pitchers. These findings suggest professional pitchers more effectively use torso power to help increase pitch speed without increasing overall joint torques.

Hip Range of Motion and Strength and Energy Flow During Windmill Softball Pitching.

Inadequate hip range of motion (ROM) and isometric strength (ISO) may interfere with energy flow through the kinetic chain and result in increased injury susceptibility. To examine the relationship of hip ROM and ISO with energy flow through the trunk and pitching-arm segments during the windmill softball pitch in youth athletes. A subsequent purpose was to examine the relationship between energy flow and pitch speed. Descriptive laboratory study. University research laboratory. A sample of 29 youth softball pitchers (age = 11.2 ± 1.3 years, height = 155.0 ± 10.4 cm, mass = 53.2 ± 12.6 kg). Bilateral hip internal-rotation and external-rotation (ER) ROM and ISO were measured. Net energy outflow and peak rates of energy outflow from the distal ends of the trunk, humerus, and forearm were calculated for the acceleration phase of the windmill softball pitch, and pitch speed was measured. Regression analysis revealed an effect of drive-hip ER ISO on the net energy flow out of the distal ends of the trunk (P = .045) and humerus (P = .002). Specifically, increased drive-hip ER ISO was associated with increased net energy outflow from the trunk to the humerus and from the humerus to the forearm. No significant effects of hip ROM or other hip ISO measures were observed. Additionally, pitchers who achieved higher peak rates of distal outflow tended to achieve higher pitch speeds. An association was present between drive-hip ER ISO and the net energy flow out of the distal ends of the trunk and humerus during the acceleration phase of the windmill softball pitch, emphasizing the importance of hip and lower body strength in executing the whole-body windmill pitch. Overall, energy-flow analysis is an interesting new way to analyze pitching mechanics and will aid in furthering our understanding of performance and injury risk in windmill softball pitching.

Kinematic Differences Exist Between the Fastball, Changeup, Curveball, and Dropball Pitch Types in Collegiate Softball Pitchers

Background: A majority of softball literature focuses on the mechanics associated with pain and injury within a single pitch type per study; however, the generalizability of these findings is unknown since a kinematic comparison has yet to be performed between pitch types. Understanding kinematic differences between pitch types can be used to identify risk factors for injury, improve safety guidelines, and improve performance by linking specific mechanics with desired pitch outcomes. Hypothesis/Purpose: The purpose of this study was to compare kinematics between the fastball, changeup, curveball, and dropball pitch types in collegiate softball pitchers. It was hypothesized that there would be significant kinematic differences between pitch types. Study Design: Descriptive laboratory study. Methods: A total of 28 female collegiate softball pitchers pitched 3 trials of each pitch type to a catcher at regulation distance. Pitch speed, stride length, trunk extension, trunk rotation, trunk lateral flexion, elbow flexion, and center of mass for each trial were calculated using an electromagnetic motion capture system and were averaged for analysis. A 1-way analysis of variance (ANOVA) was used to investigate pitch speed differences between the 4 pitch types. A 4 (pitch type) × 5 (event) within-athlete multivariate ANOVA was also used to determine kinematic differences. Results: The results revealed a significant difference in pitch speed between pitch types; a pitch type main effect for trunk extension, trunk rotation, trunk lateral flexion, and center of mass; and an event main effect for all variables except stride length. The results also revealed a pitch type by event interaction for trunk flexion, trunk lateral flexion, and center of mass. Specifically, the dropball type had less trunk extension than the fastball at all pitching events. Similarly, the curveball type had a more posteriorly shifted center of mass than the dropball at the last 3 pitching events of foot contact, ball release and follow-through. Conclusion: Significant kinematic differences exist between pitch types, but these differences may be necessary to execute desired pitch outcomes. Clinical Relevance: This is the first study to analyze kinematic differences between pitch types in softball pitchers. Understanding the effects of different pitch types on kinematic parameters may enhance injury prevention and performance strategies for softball pitchers.