Reciprocal inhibition and competitive hierarchy cause negative biodiversity-ecosystem function relationships.

The relationship between biodiversity and ecosystem function (BEF) captivates ecologists, but the factors responsible for the direction of this relationship remain unclear. While higher ecosystem functioning at higher biodiversity levels ('positive BEF') is not universal in nature, negative BEF relationships seem puzzlingly rare. Here, we develop a dynamical consumer-resource model inspired by microbial decomposer communities in pitcher plant leaves to investigate BEF. We manipulate microbial diversity via controlled colonization and measure their function as total ammonia production. We test how niche partitioning among bacteria and other ecological processes influence BEF in the leaves. We find that a negative BEF can emerge from reciprocal interspecific inhibition in ammonia production causing a negative complementarity effect, or from competitive hierarchies causing a negative selection effect. Absent these factors, a positive BEF was the typical outcome. Our findings provide a potential explanation for the rarity of negative BEF in empirical data.

Arthropod prey type drives decomposition rates and microbial community processes.

Microbial communities perform various functions, many of which contribute to ecosystem-level nutrient cycling via decomposition. Factors influencing leaf detrital decomposition are well understood in terrestrial and aquatic ecosystems, but much less is known about arthropod detrital inputs. Here, we sought to infer how differences in arthropod detritus affect microbial-driven decomposition and community function in a carnivorous pitcher plant, Sarracenia purpurea. Using sterile mesh bags filled with different types of sterile arthropod prey, we assessed if prey type influenced the rate of decomposition in pitcher plants over 7 weeks. Additionally, we measured microbial community composition and function, including hydrolytic enzyme activity and carbon substrate use. When comparing decomposition rates, we found that ant and beetle prey with higher exoskeleton content lost less mass compared with fly prey. We observed the highest protease activity in the fly treatment, which had the lowest exoskeleton content. Additionally, we saw differences in the pH of the pitcher fluid, driven by the ant treatment which had the lowest pH. According to our results from 16S rRNA gene metabarcoding, prey treatments with the highest bacterial amplicon sequence variant (ASV) richness (ant and beetle) were associated with prey that lost a lower proportion of mass over the 7 weeks. Overall, arthropod detritus provides unique nutrient sources to decomposer communities, with different prey influencing microbial hydrolytic enzyme activity and composition. IMPORTANCE: Microbial communities play pivotal roles in nutrient cycling via decomposition and nutrient transformation; however, it is often unclear how different substrates influence microbial activity and community composition. Our study highlights how different types of insects influence decomposition and, in turn, microbial composition and function. We use the aquatic pools found in a carnivorous pitcher plant as small, discrete ecosystems that we can manipulate and study independently. We find that some insect prey (flies) breaks down faster than others (beetles or ants) likely because flies contain more things that are easy for microbes to eat and derive essential nutrients from. This is also reflected in higher enzyme activity in the microbes decomposing the flies. Our work bridges a knowledge gap about how different substrates affect microbial decomposition, contributing to the broader understanding of ecosystem function in a nutrient cycling context.

Effects of isolated shoulder versus core-shoulder chain exercises on motor control and isokinetic torque in baseball pitchers with shoulder impingement syndrome: A single-blinded randomized controlled trial.

Recent biomechanical evidence suggests that shoulder impingement syndrome (SIS) is closely linked with altered core-shoulder kinetic chain, resulting pain, altered external shoulder muscle activation, and external muscle weakness. We aimed to compare the effects of conventional isolated shoulder exercise (ISE) and core-shoulder chain exercises (CCE) during isokinetic shoulder rotation in baseball pitchers with SIS. Forty male college baseball pitchers with SIS were randomly allocated to ISE and CCE groups and they performed the exercises 3 times a week for 6 weeks. The standardised numerical pain rating scale (NPRS), shoulder pain and disability index (SPADI), electromyography (EMG) amplitude, and concentric (CON) and eccentric (ECC) torques were measured. Substantial improvements in NPRS and SPADI scores were observed after CCE compared to ISE (p ≤ 0.046). Internal oblique/transversus abdominis, rectus abdominis, external oblique, serratus anterior, and infraspinatus muscle activation were significantly higher after CCE than ISE (p ≤ 0.033). CON and ECC torques were higher after CCE than ISE (p ≤ 0.002). The present findings demonstrated superior therapeutic effects of CCE in improving pain, disability level, shoulder muscle activation, and torque (muscle strength) in baseball pitchers with SIS compared to the conventional ISE, highlighting the importance of the chain exercise concept.

Relationship between the elasticity of the forearm flexor-pronator muscles and elbow valgus torque in young baseball pitchers: a descriptive laboratory study.

BACKGROUND: The forearm flexor-pronator muscles act as a dynamic elbow stabilizer against elbow valgus load during baseball pitching. The elasticity of these muscles increases with pitching. However, it is unclear whether increased muscle elasticity is associated with greater elbow valgus torque during pitching. This study aimed to determine the relationship between the elasticity of the forearm flexor-pronator muscles and elbow valgus torque during pitching in young baseball pitchers. METHODS: We recruited 124 young baseball pitchers aged 9 to 12 years. The exclusion criteria included current pain with pitching, history of surgery on the tested extremity, or injuries on the tested extremity within the past 12 months. Before the examination, participants completed a questionnaire about their age, height, weight, dominant arm and practice time per week. The strain ratios of flexor carpi ulnaris (FCU), flexor digitorum superficialis (FDS), and pronator teres as the index of muscle elasticity were measured using ultrasound strain elastography. Participants pitched three fastballs at a distance of 52 ft 6 in (16 m) with maximum effort while wearing a sensor sleeve that recorded the elbow valgus torque. A multiple linear regression analysis was conducted to examine the association between muscle elasticity and elbow valgus torque, adjusting for age, height, weight, and practice time. RESULTS: The final analysis included 107 pitchers. After adjusting for covariates, increased strain ratio of the FCU was significantly associated with greater elbow valgus torque (coefficients = 0.038, 95% confidence interval [CI], 0.016-0.059, P<.001). Similarly, increased strain ratio of the FDS was significantly associated with greater elbow valgus torque (coefficients = 0.027, 95% CI, 0.013-0.042, P<.001). CONCLUSION: The high elasticities of the FCU and FDS were associated with greater elbow valgus torque during pitching in young baseball pitchers. The high elasticity of these muscles is a protective response and may be necessary for young baseball pitchers with greater elbow valgus torque during pitching. Among young baseball pitchers with greater elbow valgus torque, those who are unable to produce the higher elasticities of these muscles could have greater elbow valgus load during pitching and be at a higher risk for elbow injuries. The measurement of the elasticities of the FCU and FDS may be useful for identifying young baseball pitchers at risk of sustaining elbow injuries.

Retrograde headless compression screw fixation of olecranon stress fractures in throwing athletes: a novel technique.

Background: An olecranon stress fracture (OSF) is a rare injury most commonly seen in high-level overhead throwing athletes with no clear consensus on surgical treatment. The most common surgical treatment described in the literature is cannulated screw fixation but there have been high rates of reported hardware irritation and need for subsequent hardware removal. Hypothesis/Purpose: This study describes a novel surgical technique in the treatment of OSFs in high-level throwing athletes using retrograde headless compression screws. We hypothesized that patients would have excellent outcomes and decreased rates of hardware irritation postoperatively. Methods: A retrospective review of competitive-level throwing athletes who sustained OSFs that were treated operatively using a novel technique using retrograde cannulated headless compression screws to avoid disruption of the triceps tendon. Postoperative outcome measures obtained included the Disabilities of the Arm, Shoulder and Hand score, Mayo Elbow Performance Score, Simple Elbow Test score, Single Assessment Numerical Evaluation score, Visual Analog Scale, arch of motion, and time to return to sport as well as level returned to. Radiographs were obtained routinely at 2-week, 6-week, 12-week, 6-month, 1-year, and 2-year follow-up. Results: Five of 5 patients who met inclusion criteria were available for final follow-up. Mean age at time of surgery was 20 years (range 17-24). Mean follow-up was 17 months (range 4-33). All patients were baseball players, 4 of which were pitchers and 1 position player. All patients were able to return to sport at the same level or higher at a mean of 5.8 months (range 3-8). Postoperatively, mean arch of motion was 138°, Visual Analog Scale score was 0, Single Assessment Numerical Evaluation score was 90, Disabilities of the Arm, Shoulder and Hand score was 2.0, Mayo Elbow Performance Score was 100, and Simple Elbow Test score was 12. There was no incidence of hardware removal. Conclusion: This study presents a novel surgical technique in the treatment of OSFs in high-level throwing athletes. The results presented demonstrate that this technique is safe and effective for getting athletes back to play quickly without any complications of hardware irritation which has previously shown to be a significant problem in prior literature.

The efficacy of injecting a distillate of the pitcher plant (Sarraceniaceae) adjacent to the palmar digital nerves of horses to ameliorate lameness caused by digital pain.

This study aimed to determine the efficacy of instilling extract of the pitcher plant around the palmar digital nerves of horses to ameliorate digit pain causing lameness. Five mixed breed horses were recruited. Horses were determined to be lame because of pain in the distal portion of one or both thoracic limbs by a positive response to a basisesamoid nerve block using 2%^mepivacaine hydrochloride. Gait was evaluated pre- and post-nerve block at 30 min, 3, 7,14 and 21 days. At the 3-week evaluation, the basisesamoid nerve block was repeated using the extract, and the gait was evaluated at similar times. Lameness was evaluated objectively using a wireless, inertial, sensor-based, motion analysis system. The basisesamoid nerve block significantly ameliorated lameness at 30 min when gait was evaluated, but it had no significant effect on lameness after this time. The product containing extract of the pitcher plant had no significant effect on lameness when administered as a basisesamoid nerve block at any time. Extract of the pitcher plant administered adjacent to the medial and lateral palmar digital nerves (i.e., a basisesamoid nerve block) had no efficacy in ameliorating lameness in the distal portion of one or both thoracic limbs. Extract of the pitcher plant likely has no value for treating horses for chronic pain when administered as a regional nerve block.

Changes in Pitch Velocity and Selection in Major League Baseball Pitchers Following the Ulnar Collateral Ligament Reconstruction.

BACKGROUND: The ulnar collateral ligament (UCL) is a soft-tissue stabilizer of the elbow, that is commonly injured among baseball pitchers due to excess valgus stress in overhead throwing motions. The location of a UCL tear typically ranges from the central aspect of the ligament to an avulsion-type injury at its proximal insertion site on the medial epicondyle of the humerus, or its distal insertion site on the ulna. The effect of UCL reconstruction on pitching performance has become a well-studied topic in medical literature. In our study, we aimed to identify general performance patterns amongst those having undergone UCL reconstruction surgery. METHODS: Data for patients with UCL reconstruction performed between 2010 and 2020 were extracted from publicly available databases. Pitching data was extracted from Brooks Baseball, a publicly available database for Major League Baseball (MLB) player statistics. We identified patients who played at least one full season after surgery and rehabilitation. Patient characteristics were evaluated for intergroup differences. RESULTS: Of 109 patients with UCL reconstruction, 87 were included in the final analysis. Compared to the preoperative group, the average postoperative fastball usage rate was less despite there being an increase in the off-speed usage rate. Velocity analysis demonstrated shifts of less than 1% for all three pitch groups compared to preoperative velocity average values (all P-values <0.05). Earned Run Average (ERA)+ demonstrates a decrease in the postoperative group; this finding was not significant (P=0.61). CONCLUSIONS:  Patients treated surgically demonstrated a throwing tendency for their secondary and tertiary pitches and a decreased usage of fastballs. Further studies are needed to explore the factors contributing to the change in pitching performance.

Comparison of ground reaction force among stride types in baseball pitching.

This study aims to investigate the different ground reaction force (GRF) characteristics from different stride types. This study included 30 Taiwanese elite college and professional baseball pitchers. Each pitcher was classified into one of the following stride types: tall and fall (TF), dip and drive (DD), or mixed (MX). Our findings indicated that DD pitchers pressed their bodies forward earlier than TF pitchers. In contrast, the GRF of the pivot leg of TF pitchers increased slowly in the first half of the stride phase and continued to increase even after the stride leg touched the ground. This type of continuous pressing in TF was different from that in DD and MX pitchers, which decreased rapidly into the arm-cocking & acceleration phases. We conclude that the lower extremities were used differently by TF, DD and MX pitchers. This information could serve as a training guideline for coaches and pitchers to enhance training effectiveness, while simultaneously lowering injury risks.

Chronic Adaptation of the Coracohumeral Space and Subscapularis Tendon in Professional Baseball Pitchers.

BACKGROUND: Pitchers frequently experience anterior shoulder pain, possibly associated with coracohumeral impingement; however, whether the coracohumeral distance (CHD) and/or subscapularis tendon adapt chronically (bilateral difference) due to pitching, and whether clinical measures are associated with CHD and subscapularis tendon organization have not been evaluated in professional pitchers. HYPOTHESIS: The authors hypothesized that dominant arm CHD would be smaller than the nondominant arm, dominant subscapularis tendon would have increased spatial frequency (ie, be more disorganized), and humeral retroversion (HR) would predict CHD and subscapularis tendon organization. LEVEL OF EVIDENCE: Level 4. METHODS: Healthy professional baseball pitchers were recruited during their preseason physical examination. Bilateral diagnostic ultrasound measured CHD, HR, and posterior capsule thickness (PCT), and quantified subscapularis tendon organization. External rotation, neutral, and crossbody CHD was measured. RESULTS: Overall, 52 healthy professional baseball pitchers participated. The dominant arm of pitchers demonstrated a significantly narrower CHD in all 3 positions (P < 0.01), increased scapular protraction (163 vs 156 mm; P < 0.01), and increased spatial frequency of the subscapularis tendon (1.8 vs 1.6 peaks/mm; P < 0.01). HR was associated with CHD in 30° of external rotation (R2 = 0.12; P < 0.01), neutral rotation (R2 = 0.11; P < 0.01), and the crossbody position (R2 = 0.28; P < 0.01). PCT was associated with CHD in 30° of external rotation (R2 = 0.16; P = 0.05). HR and CHD in 30° of external rotation was associated most strongly with subscapularis tendon organization (R2 = 0.11; P = 0.03). CONCLUSION: The dominant shoulder of professional pitchers presents with a smaller CHD, more scapular protraction, and more subscapularis tendon disorganization than the nondominant shoulder. CLINICAL RELEVANCE: Professional pitchers demonstrate chronic CHD and subscapularis tendon adaptations, which may increase their risk for anterior shoulder pain and subscapularis tendon injury.

Is There a Relationship Between Grip Strength and Injuries in Professional Baseball Players?

Background: Injuries in professional baseball players have become exceedingly common. Efforts to mitigate injury risk have focused on the kinetic chain, shoulder motion, and so forth. It is unclear whether grip strength is related to injury risk in professional baseball pitchers. Purpose/Hypothesis: The purpose of this study was to determine if grip strength was a risk factor for injury. It was hypothesized that pitchers with weaker grip strength would have a higher likelihood of sustaining a shoulder or elbow injury compared with pitchers with stronger grip strength. Study Design: Case-control study; Level of evidence, 3. Methods: All professional pitchers from a single Major League Baseball organization were included. Dominant and nondominant grip strength were measured after each pitching outing throughout the 2022 season. Injuries over the course of the season were recorded, and data were compared between pitchers who sustained a shoulder or elbow injury and those who did not. Results: Overall, 213 pitchers were included, of whom 53 (24.9%) sustained a shoulder or elbow injury during the season. The mean grip strength for all pitchers was 144.0 ± 20.8 lb (65.3 ± 9.4 kg). The mean dominant-arm grip strength was 142.6 ± 20.8 lb (64.7 ± 9.4 kg) for pitchers who did not sustain a shoulder or elbow injury and 148.2 ± 20.9 lb (67.2 ± 9.5 kg) for pitchers who did sustain an injury, with no significant group difference in grip strength (P > .05). Furthermore, there were no significant differences in change in grip strength over the course of the season between the groups. Conclusion: There was no significant difference in mean grip strength or change in grip strength over the course of a single season between professional baseball pitchers who sustained a shoulder or elbow injury and those who did not.

From Dugout to the Mound: A Tale of Platelet-Rich Performance.

Ulnar collateral ligament (UCL) tears of the elbow are prevalent injuries among throwing athletes and are associated with excessive or repeated valgus forces at the elbow. We present the case of an 18-year-old male baseball pitcher with an 18-month history of progressive right elbow pain, notably worsened during his fastball pitching. Clinical assessment revealed tenderness with dynamic stressing of the right UCL. Imaging analyses, including magnetic resonance imaging (MRI) and dynamic ultrasound, confirmed a high-grade partial tear of the UCL at its origin. Non-operative management was pursued, which included an ultrasound-guided platelet-rich plasma (PRP) injection and intensive physical therapy. Follow-up evaluations at six and 12 weeks demonstrated a noteworthy improvement in subjective pain descriptions and structural healing of the UCL. After the patient completed a therapy and rehabilitation program, throwing activities at full strength were able to be resumed. This case underscores the potential efficacy of conservative approaches in handling UCL tears with the inclusion of PRP as a viable treatment option.

Fundamentos físicos del gesto técnico del pitcher / Fundamentos físicos do gesto técnico do lançador / Physical foundations of the pitcher's technical gesture

RESUMEN La codicia por lanzar duro en el béisbol, más el desconocimiento mecánico-energético del aporte y lo que evita la correcta ejecución de las fases del gesto técnico del pitcher, resultaron ser las principales causas de las lesiones y el motivo de una investigación explicativa, a través de la aplicación de métodos físicos cinemáticos, dinámicos y energéticos, en el estudio de la manifestación de leyes físicas durante la observación no participativa de su desempeño, al lanzar la pelota, tanto en lanzadores nacionales como internacionales y de testimonios de personas con experiencias como pitcher. El objetivo de este artículo consistió en proponer una explicación física de cómo funciona la biomecánica del cuerpo del pitcher durante los gestos técnicos del lanzamiento para garantizar una bola rápida y minimizar lesiones. Con este trabajo, se pretendió, además, instruir al pitcher de cómo funciona la biomecánica de su cuerpo durante el lanzamiento de la pelota, aprovechando ventaja de la altura del montículo con argumentos desde la ciencia Física; esto contribuyó a lanzamientos más rápidos, elegantes y a minimizar lesiones. Como resultado, se elaboró una explicación física por fases para el pitcher, además, un sistema masa-resorte aislado para experimentar movimientos biomecánicos y energéticos, que evidenciaron en su desempeño manifestaciones de las leyes físicas de la mecánica clásica de Newton, de la conservación de la energía mecánica, del momento cinético y del momento angular.

RESUMO A ganância de jogar duro no basebol, mais a ignorância mecânico-energética da contribuição e o que impede a correta execução das fases do gesto técnico do lançador, revelaram-se as principais causas de lesões e a razão de uma pesquisa explicativa, através da aplicação de métodos físicos cinemáticos, dinâmicos e energéticos, no estudo da manifestação das leis físicas durante a observação não participativa do seu desempenho, ao lançar a bola, tanto em lançadores nacionais como internacionais e testemunhos de pessoas com experiências como lançadores. O objetivo deste artigo é propor uma explicação física de como funciona a biomecânica do corpo do lançador durante os gestos técnicos de lançamento para garantir uma bola rápida e minimizar as lesões. Com este trabalho, pretende-se também instruir o lançador sobre como funciona a biomecânica do seu corpo durante o lançamento da bola, tirando partido da altura do monte com argumentos da ciência física. Isto contribui para campos mais rápidos e mais elegantes e para minimizar as lesões. Como resultado, foi elaborada uma explicação física por fases para o jarro, além disso, um sistema isolado de suspensão em massa para experimentar movimentos biomecânicos e energéticos, que evidenciou no seu desempenho, manifestações das leis físicas da mecânica clássica de Newton, da conservação da energia mecânica, do momento cinético e do momento angular.

ABSTRACT The greed to throw hard in baseball, plus the mechanical-energetic ignorance of the contribution and what prevents the correct execution of the phases of the pitcher's technical gesture, turned out to be the main causes of injuries and the reason for an explanatory research, through the application of physical kinematic, dynamic and energetic methods, in the study of the manifestation of physical laws during the non-participatory observation of their performance, when throwing the ball, both in national and international pitchers and testimonies of people with experiences as pitchers. The objective of this article is to propose a physical explanation of how the biomechanics of the pitcher's body works during the technical gestures of pitching to guarantee a fast ball and minimize injuries. With this work, it is also intended to instruct the pitcher on how the biomechanics of his body works during the pitching of the ball, taking advantage of the height of the mound with arguments from the physical science. This contributes to faster, more elegant pitches and to minimize injuries. As a result, a physical explanation by phases was elaborated for the pitcher, in addition, an isolated mass-spring system to experiment biomechanical and energetic movements, which evidenced in their performance manifestations of the physical laws of Newton's classical mechanics, conservation of mechanical energy, kinetic momentum and angular momentum.

Indicadores de rendimiento deportivo para el proceso de selección del lanzador abridor / Indicadores de desempenho esportivo para o processo de seleção de batedores iniciais / Sports performance indicators for the opening pitcher selection process

RESUMEN El talento deportivo no se define por una sola capacidad, sino por la interrelación y complementación, lo que implica análisis y valoraciones integrales. En el béisbol, a pesar de que cuenta con programas de preparación del deportista, actualizados y de parámetros establecidos para la selección deportiva, aún continúan siendo deficientes los indicadores que permiten una selección objetiva para cumplir funciones especializadas, lo que constituye un aspecto de esencial importancia en el desempeño competitivo contemporáneo. Sin embargo, en el proceso de conformación de los equipos a participar en campeonatos nacionales, se evidencian insuficiencias que limitan la calidad de su alcance. De ahí que el objetivo general de la investigación consistió en proponer indicadores de rendimiento deportivo para el proceso de selección del lanzador abridor, en la conformación de equipos de béisbol de alto rendimiento en la Isla de la Juventud. Se seleccionó una muestra compuesta por 11 lanzadores de béisbol de la categoría juvenil de la Isla de la Juventud que representa el 52,38 % de la población; de ellos, ocho son derechos que representan el 72.72 % y tres zurdos que representan el 27.27 %, además de cuatro entrenadores que representan el 19,04 % y 6 especialistas que representan 28,57 % de la población. Los métodos de investigación empleados fueron la observación, revisión de documentos normativos que rigen el proceso de selección deportiva en el béisbol, la encuesta a entrenadores y el criterio de especialistas, lo que permitió identificar la inexistencia de una herramienta que oriente la labor del profesor deportivo en lo referido a la selección de los lanzadores abridores.

RESUMO O talento esportivo não é definido por uma única capacidade, senão pela inter-relação e complementação, que envolve análise e avaliações abrangentes. No beisebol, apesar de ter atualizado programas de preparação dos atletas e estabelecido parâmetros para a seleção esportiva, os indicadores que permitem uma seleção objetiva para cumprir funções especializadas ainda são deficientes, o que é um aspecto de importância essencial no desempenho competitivo contemporâneo. Entretanto, no processo de conformação das equipes para participar de campeonatos nacionais, existem insuficiências que limitam a qualidade de seu escopo. Assim, o objetivo geral da pesquisa foi propor indicadores de desempenho esportivo para o processo de seleção do arremessador titular, na conformação de equipes de beisebol de alto rendimento na Ilha da Juventude. Foi selecionada uma amostra composta por 11 jogadores de beisebol da categoria jovem da Ilha da Juventude, representando 52,38 % da população; oito deles são destros, representando 72,72 % e três são canhotos, representando 27,27 %, além de quatro treinadores representando 19,04 % e 6 especialistas representando 28,57 % da população. Os métodos de pesquisa utilizados foram a observação, a revisão de documentos normativos que regem o processo de seleção esportiva no beisebol, o levantamento dos treinadores e os critérios dos especialistas, o que permitiu identificar a inexistência de uma ferramenta para orientar o trabalho do professor de esportes em relação à seleção dos arremessadores iniciantes.

ABSTRACT Sports talent is not defined by a single capacity, but by the interrelation and complementation, which implies comprehensive analysis and assessments. In baseball, in spite of having updated athlete preparation programs and established parameters for sports selection, the indicators that allow an objective selection to fulfill specialized functions are still deficient, which is an aspect of essential importance in contemporary competitive performance. However, in the process of forming the teams to participate in national championships, there are insufficiencies that limit the quality of their scope. Hence, the general objective of the research consisted in proposing sports performance indicators for the selection process of the opening pitcher, in the conformation of high performance baseball teams in La Isla de la Juventud. A sample composed of 11 baseball pitchers of the youth category of La Isla de la Juventud was selected, representing 52.38 % of the population; of them, eight are right-handed representing 72.72 % and three are left-handed representing 27.27 %, in addition to four coaches representing 19.04 % and 6 specialists representing 28.57 % of the population. The research methods used were observation, review of regulatory documents governing the process of sports selection in baseball, the survey of coaches and the criteria of specialists, which allowed identifying the lack of a tool to guide the work of the sports teacher in relation to the selection of the opening pitchers.

Efectividad en la zona de strike de los lanzadores pinareños / Eficácia na zona de strike dos lançadores de Pinar del Rio / Effectiveness in the strike zone of the pitchers from Pinar del Río

Resumen Teniendo presente la importancia del pitcheo y su peso para el éxito en el juego de béisbol, es que el objetivo de la investigación se centra en analizar la efectividad en la zona de strike de los lanzadores del equipo de béisbol de Pinar del Río, primera categoría, participantes en la Serie Nacional. Par ello, se trabajó con una población integrada por los 13 lanzadores que constituyen el staff de pitcheo y los dos entrenadores responsables de la preparación de estos en dicho equipo. Se emplearon métodos y técnicas científicas como el análisis de la estadística de cada uno de los juegos, así como la observación, la encuesta y la entrevista. El análisis de los resultados obtenidos revela que el 61,5 % de los lanzadores del equipo, fundamentalmente los más jóvenes, presentan problemas con el control de los lanzamientos en la zona de strike, aflorando una serie de insuficiencias relacionadas con el dominio de la mecánica de pitcheo, el escaso repertorio de lanzamientos, unido a un bajo dominio sobre los mismos, entre otros elementos vinculados a la preparación. Estos resultados, junto al control sistemático y análisis de la labor de los lanzadores durante los juegos, constituyen elementos importantes para trazar estrategias más eficientes en la preparación de estos atletas, atemperadas a sus particularidades individuales e insuficiencias, en aras de lograr una mayor efectividad de los mismos, y, por ende, superar los resultados competitivos del equipo.

Resumo Tendo em conta a importância do lançamento e o seu peso para o sucesso no jogo de basebol, o objectivo do presente trabalho está centrado na análise da efetividade na zona de strike dos lançadores da equipe de basebol de Pinar del Río, primeira categoria, participantes da Série Nacional. Para isso, trabalhamos com uma população composta pelos 13 lançadores que integram a equipe de pitcheo e os dois técnicos responsáveis pela preparação destes em tal equipe, para o qual foram utilizados métodos e técnicas científicas, como a análise das estatísticas de cada um dos jogos, assim como a observação, o inquérito e a entrevista. A análise dos resultados obtidos revela que 61,5% dos lançadores da equipe, principalmente os mais jovens, apresentam problemas com o controle dos lances na zona de strike, revelando uma série de deficiências relacionadas com o domínio da mecânica de lançamento, o escasso repertório de lançamentos, juntamente com um domínio baixo sobre os mesmos, entre outros elementos ligados à preparação. Estes resultados, juntamente com o controle e análise sistemática do trabalho dos lançadores durante os jogos, constituem elementos importantes para traçar estratégias mais eficientes na preparação destes atletas, temperados às suas particularidades e insuficiências individuais, a fim de alcançar uma maior efetividade dos mesmos e, portanto, para superar os resultados competitivos da equipe.

Abstract Bearing in mind the importance of pitching and its weight for the success in the baseball game, the objective of the present work is focused on the analysis of the effectiveness in the strike zone of the pitchers of the Pinar del Río baseball team, first category, participants in the national series. For this purpose, it was worked with a population integrated by the 13 pitchers that constitute the pictching staff and the two coaches responsible for the preparation of these in such team, for which we used scientific methods and techniques such as the analysis of the statistics of each one of the games, as well as observation, survey and interview. The analysis of the results obtained reveals that 61,5 % of the pitchers of the team, mainly the youngest ones, present problems with the control of the throws in the strike zone, revealing a series of deficiencies related to the domain of the mechanics of pick-up, the scarce repertoire of throws, together with a low domain on the same ones, among other elements linked to the preparation. These results, together with the systematic control and analysis of the work of the throwers during the games, constitute important elements to trace more efficient strategies in the preparation of these athletes, tempered to their individual particularities and insufficiencies, in order to achieve a greater effectiveness of the same and therefore to overcome the competitive results of the team.

Metodología para el perfeccionamiento del accionar técnico táctico de los lanzadores de béisbol / Methodology for the improvement of the tactical technical action of baseball pitchers

Resumen El accionar técnico táctico de los lanzadores de béisbol exige la búsqueda de herramientas novedosas que se deriven en un contexto pedagógico que gestione, de manera creativa, las formas del conocimiento; a tono con esto, las metodologías actuantes en béisbol reclaman una continua actualización en el orden teórico, metodológico y práctico. De ahí que la presente investigación tuvo por objetivo elaborar una metodología para el perfeccionamiento del accionar técnico-táctico de los lanzadores de béisbol, en correspondencia con la función que desempeñan dentro del juego. Para ello se trabajó con una muestra primaria de 15 lanzadores del equipo Pinar del Río, en el último año de la categoría 17-18, así como una muestra secundaria de 12 entrenadores, 20 especialistas y 20 atletas que incursionan regular u ocasionalmente como lanzadores. Se emplearon métodos y técnicas científicas de investigación como el análisis de documentos, la observación, la entrevista estandarizada e individual y el criterio de expertos. Se constataron carencias en el tratamiento del contenido de la preparación técnico-táctica para el perfeccionamiento del accionar del lanzador de béisbol, según la función que desempeña en el juego, a partir de la cual se propone una metodología que contiene la estructura, contenido y planificación de la preparación técnica-táctica de los lanzadores de béisbol, según su función en el juego, a partir de situaciones simplificadas que didácticamente actúan sobre los componentes de esta preparación deportiva y bajo leyes y principios del entrenamiento deportivo.

Abstract The technical tactical action of baseball pitchers requires the search for new tools that are derived in a pedagogical context that creatively manages the forms of knowledge, in line with this, the methodologies used in baseball demand a continuous updating in the theoretical, methodological and practical order. Hence, the objective of the present research was to develop a methodology for improving the tactical technical action of baseball pitchers in correspondence with the function they perform within the game. In order to do this, we worked with a primary sample of 15 pitchers from the Pinar del Río team, in the last year of the 17-18 category, as well as a secondary sample of 12 coaches, 20 specialists and 20 athletes who regularly or occasionally enter as pitchers. Scientific research methods and techniques such as document analysis, observation, standardized and individual interviews and expert judgment were used. There were shortcomings in the treatment of the contents of the tactical technical preparation for improving the actions of the baseball pitcher according to the role played in the game, from which a methodology is proposed that contains the structure, content and planning of the technical-tactical preparation of baseball pitchers, according to their function in the game, from simplified situations that didactically act on the components of this sports preparation and under laws and principles of sports training.

Comparison of passive torque during shoulder internal rotation before and after a pitching in college baseball pitchers / 体力科学

Previous study reported that baseball pitchers had a decreased shoulder internal rotation (IR) range of motion after pitching. However, whether the decreased range of motion associated with pitching is caused by tightness of the posterior shoulder has not been clarified yet. The joint stiffness in the passive torque can be compared with posterior shoulder tightness before and after pitching. Hence, this study aimed to compare shoulder IR stiffness based on passive torque before and after pitching in baseball pitcher. Eleven health male collage baseball pitchers were recruited. Passive torque during IR (max IR, peak torque and stiffness) of dominant and non-dominant arms was measured using an isokinetic dynamometer. Measurements were taken before, after, and post 24 hours after pitching (105 pitches). It was observed that after pitching, max IR and peak torque were significantly decreased compared to those before pitching. However, there was no difference in the stiffness of passive torque among three measurements. In conclusion, healthy college baseball pitchers have a decreased IR range of motion after pitching. However, this result is not due to posterior shoulder tissue tightness, but because of altered stretch tolerance.

Elbow Impingement Syndrome in Athletes / 대한스포츠의학회지

Overhead athletes often suffer from elbow injuries due to repetitive throwing movements. In particular, in the baseball pitching motion, a high shear torque generated in the late corking and early acceleration stage causes tensile loads on the medial elbow and shear force on the posterior of the elbow. These repetitive movements can lead to valgus extension overload syndrome. The valgus extension overload syndrome mainly occurs in overhead athletes, and is characterized by limited elbow flexion and pain at the end of extension. It is necessary to differentiate from the stress fracture or the avulsion fracture of the olecranon which complain of posterior elbow pain through computed tomography. The treatment is primarily rehabilitation that restricts the elbow motion. If refractory or mechanical symptoms persist, arthroscopic surgery may be an effective treatment modality for the removal of the osteophytes. In the surgical field, it is desirable to reconstruct the medial collateral ligament when it is confirmed that the ligament is ruptured. Patients who underwent arthroscopic removal of olecranon osteophytes had immediate active elbow exercises and for 3 months were prohibited from pitching exercises. During this period, they were rehabilitated with the focus on strengthening muscles around the scapula, rotator cuff and shoulder. After 3 months, the pitching exercise is gradually started. Six months after the operation, the elbow strength should be restored to the level at which the game starts. Patients who underwent a combined ulnar collateral ligament reconstruction, half pitching are allowed at 6 months.

Shoulder and Elbow Injury Rates and Patterns in Korean Rookie Professional Baseball Pitchers

BACKGROUND: To investigate how many rookie pitchers suffered from injuries while playing in the amateur league without guidelines for prevention of excessive pitching, we analyzed their amateur pitching patterns based on the pitch count, use of breaking balls, and pitches during winter camp. METHODS: Forty-one rookie pitchers who graduated from high school or university in 2013 and joined professional baseball teams. Participants were interviewed by a trainer using our questionnaire. Injury inclusion criteria were 1) history of shoulder surgery, 2) history of elbow surgery, 3) shoulder pain requiring treatment, and 4) elbow pain requiring treatment. RESULTS: Mean number of pitches per game and warm-up pitches for practice was 84.5 pitches (range, 15 to 130 pitches) and 16.4 pitches (range, 2 to 210 pitches), respectively. Mean number of pitches during the last year was 906.9 (range, 80 to 2,000). Mean number of maximal pitches was 127 pitches (range, 50 to 210 pitches). Fourteen pitchers had pitched over 150 pitches. Twenty-seven pitchers (65.9%) had pitched in spite of enduring pain. During winter training (mean 1.8 months), mean number of pitches per day was 162.5 pitches, and 20 pitchers (48.8%) had practiced pitching excessively despite the cold weather. Twenty-six rookies (63.4%) had shoulder pain or history of shoulder surgery, and 31 pitchers (75.6%) had elbow pain or history of elbow surgery. Only four participants (9.8%) did not have pain and history of surgery. CONCLUSIONS: For young baseball pitchers, guidelines for prevention of excessive pitching and for regulating the winter training program may be needed.

Shoulder and Elbow Injury Rates and Patterns in Korean Rookie Professional Baseball Pitchers

BACKGROUND: To investigate how many rookie pitchers suffered from injuries while playing in the amateur league without guidelines for prevention of excessive pitching, we analyzed their amateur pitching patterns based on the pitch count, use of breaking balls, and pitches during winter camp. METHODS: Forty-one rookie pitchers who graduated from high school or university in 2013 and joined professional baseball teams. Participants were interviewed by a trainer using our questionnaire. Injury inclusion criteria were 1) history of shoulder surgery, 2) history of elbow surgery, 3) shoulder pain requiring treatment, and 4) elbow pain requiring treatment. RESULTS: Mean number of pitches per game and warm-up pitches for practice was 84.5 pitches (range, 15 to 130 pitches) and 16.4 pitches (range, 2 to 210 pitches), respectively. Mean number of pitches during the last year was 906.9 (range, 80 to 2,000). Mean number of maximal pitches was 127 pitches (range, 50 to 210 pitches). Fourteen pitchers had pitched over 150 pitches. Twenty-seven pitchers (65.9%) had pitched in spite of enduring pain. During winter training (mean 1.8 months), mean number of pitches per day was 162.5 pitches, and 20 pitchers (48.8%) had practiced pitching excessively despite the cold weather. Twenty-six rookies (63.4%) had shoulder pain or history of shoulder surgery, and 31 pitchers (75.6%) had elbow pain or history of elbow surgery. Only four participants (9.8%) did not have pain and history of surgery. CONCLUSIONS: For young baseball pitchers, guidelines for prevention of excessive pitching and for regulating the winter training program may be needed.

Scapulothoracic Bursitis in a Amateur Baseball Pitcher / 대한스포츠의학회지

Scapulothoracic bursitis refers to inflammation of the bursae secondary to trauma or overuse owing to sports activities or work. It usually causes persistent pain and scapulothoracic crepitus by irritation of bursa but can be presented as painless mass around chest wall. We report a case of scapulothoracic bursitis in a baseball pitcher presenting as rapidly growing chest wall mass confused with a soft tissue tumor. Computed tomography and magnetic resonance imaging revealed as a well-demarcated cystic mass situated between the scapula and chest wall. Incisional drainage resulted in complete resolution of the mass within a couple of weeks. Scapulothoracic bursitis may be presented as painless huge mass in overhead sports athlete and one of the differential diagnoses of soft tissue tumor of the chest wall.