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OBJECTIVES The purpose of this study was to investigate the effects of 6 weeks of kettlebell training and kinesio taping applied to amateur baseball players on throwing velocity and isokinetic strength. METHODS The subjects of this study were 17 young men with more than 2 years of experience as amateur baseball players. To determine the effect of kettlebell training and kinesio training on throwing velocity and isokinetic strength, subject were divided into three group: kettlebell and kinesio taping, baseball training group (KTBG), kinesio taping group and baseball training (TBG), baseball training group (BG). Three groups trained three times a week for six weeks, and differences in shoulder isokinetic strength and throwing velocity were analyzes from pre to post training. RESULTS In the KTBG group, significant changes in the isokinetic muscle function of the shoulder joint were observed over time in both extensor strength (p=0.042) and flexor strength (p=0.017) at 60°/sec, as well as in extensor strength (p=0.028) and flexor strength (p=0.002) at 180°/sec. In the TBG group, only flexor strength at 180°/sec (p=0.020) showed significant changes. In the BG group, no significant changes were observed over time. The group interaction effect on isokinetic muscle function was not statistically significant. There were no significant changes in pitching velocity over time, and no group interaction was observed. CONCLUSIONS Therefore, a combination of 6 weeks of kettlebell training and Kinesio taping can improve the isokinetic extensor and flexor strength of the shoulder joint. Applying Kinesio taping during training can enhance the isokinetic extensor strength (180°/sec) of the shoulder joint. However, this exercise did not result in an increase in pitching velocity, and no interaction effect was observed, indicating the need for further research.

Our study aimed to investigate characteristics of jump distance and body size of 85 asymptomatic elementary school baseball players with abnormal humeral medial epicondyles. The following parameters were recorded: age, body size, bilateral forward jump distance, bilateral single forward, and lateral jump. Elbow injuries were classified based on physical examination findings of throwing pain and tenderness at the medial elbow joint and ultrasonographic findings. The distance jumped values were normalized by height. Participants with humeral medial epicondylar fragmentation, no tenderness, and subjective pain were classified as abnormal. Healthy group comprised those with no elbow pain or ultrasonographic findings. The two groups were compared using unpaired t-test. Abnormal and healthy groups comprised 15 and 62 participants, respectively. Bilateral single lateral jump distance of the abnormal group was significantly smaller than that of the healthy group. Age and body size of the injury group were significantly larger than those of the healthy group. Our study showed that the abnormal group had decreased bilateral single lateral jump and increased age and body sizes compared to those of the healthy group. [ABSTRACT FROM AUTHOR]

OBJECTIVES This study aimed to compare the functional movement screen (FMS) scores of baseball players according to their careers, for the purpose of injury prevention and healthcare programs. METHODS The study subjects were evaluated by measuring the differences in the seven fundamental movement patterns of FMS between groups according to their baseball career stages. The study included 27 college baseball players and 17 middle and high school baseball players, and analysis was conducted using STATA Version 15.0 (STATA Corp., College Station, TX, USA). RESULTS In the FMS total score, the rate of poor FMS total score (≤14) was statistically higher in 96.3% of the college baseball player than 41.18% of the middle and high school baseball player (p

Copyright of Journal of Japanese Association for Human Auxology is the property of Japanese Association for Human Auxology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Japanese Association for Human Auxology is the property of Japanese Association for Human Auxology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We examined skill-based differences in the anticipation of ball direction during the catching of a grounder in baseball. In Experiment 1, we used film stimuli which included a sequence of pitching and hitting action from the shortstop's customary perspective, and participants judged the ball's direction (left or right). Also, we used white-circle stimuli, and participants reported whether the circle was displaced to the left or to the right. Baseball players responded faster than non-players in the film task, but there was no significant difference between the two groups in the white-circle task. In Experiment 2, we used film stimuli which were cut off at four different temporal occlusion periods to examine the time of extraction of important visual cues. Accuracy exceeded the chance level prior to the bat-ball contact in both groups, but was earlier for players than for non-players. Our results suggest that players may extract anticipatory visual cues more effectively and earlier than non-players. [ABSTRACT FROM AUTHOR]

In this study, longitudinal changes in the pitching motion were analyzed using a high-speed camera in young baseball players during the growth period. The results showed no marked longitudinal changes in the trunk, lower extremities, hip joint movements, or ball release point, but the ball speed increased significantly. The height and body weight also increased significantly over one year. Young baseball players in this period show an immature pitching motion depending on upper extremity movements; thus, the marked increase in the ball speed was considered to be due to improvement in body size and strength. In addition to the "quality" of the pitching motion, young baseball players in the growth period are also considered to perform an increased "number" of pitches and exhibit such physical problems as a decreased range of motion in the shoulder and hip joints and decreased muscular flexibility of the lower extremities; they also frequently develop joint pain posterior shoulder and the inside of the elbow. [ABSTRACT FROM AUTHOR]

Aim: We developed a subjective assessment score for baseball throwing performance. The aim of this study was to investigate the usefulness of this subjective assessment score in high school baseball players. Materials and Methods: We evaluated 1,024 high school baseball players. They were assessed using the DASH sports module, KJOC score, and throwing performance score. The throwing performance score had a minimum value of 0% and a maximum value of 100%. Statistical correlations between these assessments were determined. Results: The mean DASH sports module score was 18.3 points, the mean throwing performance score was 71.2%. Significant correlations were found between the throwing performance and the DASH sports module score, between the throwing performance and the KJOC score, and between the DASH sports module and the KJOC score. Conclusion: All of these questionnaires are useful to assess throwing performance problems in baseball players. [ABSTRACT FROM AUTHOR]

Aim: We investigated the relationship between playing position of body pain in high school baseball players. Materials Methods: We enrolled 1,024 high school baseball players. The numbers of players by position were 249 pitchers, 119 catchers, 432 infielders; and 143 of them played more than one position. After the fall baseball season ended, subjects were given questionnaires and were assessed quantitatively regarding their regions of body pain. Based on this information, we analyzed the relationship between playing position and region of body pain. Results: The incidence of shoulder and upper arm pain was the highest in catchers, the incidence of elbow and forearm pain was the highest in pitchers, and the incidence of wrist and hand pain was the highest in outfielders. Conclusion: Our results suggest that the incidence of upper extremity pain differs depending on the baseball playing position. [ABSTRACT FROM AUTHOR]

The purpose of the study was to investigate the relationship between disc degeneration (DD) and physical characteristics in male collegiate rubber baseball players. Physical characteristics of 61 rubber baseball players, such as range of motion, joint flexibility, and muscle tightness, were analyzed. DD was evaluated using T2-weighted magnetic resonance images. The degree of degeneration was classified into 5 grades according to the Pfirrmann classification, and the presence of grade 3 or higher was considered to represent degeneration. According to this evaluation, we assigned all players to 2 groups, the DD group (n = 21) and the non-DD group (n = 40). The results showed that weight, body mass index (BMI), and the range of motion of the thoracolumbar region during left rotation were significantly higher in the DD group than the non-DD group (p<0.05). In conclusion, we considered that the relative weight, BMI and increased range of motion of the thoracolumbar region during left rotation have effect on DD in male collegiate rubber baseball players. [ABSTRACT FROM AUTHOR]

In our study series, we analyzed characteristics regarding the throwing motions of 2,105 baseball players of various ages in different fielding positions (pitchers, catchers, infielders, and outfielders) using a high-speed camera. In this paper, as Part 2, we report the analysis of the characteristics regarding the motions of the lower extremities and hip joint in the sagittal plane during the acceleration phase. As the result, we observed that it is possible to specify the pitcher's proper throwing motion as a good for each age group, namely the motion related to the angles of the thigh, hip joint, and knee joint in the sagittal plane, and the step width for late elementary school pupils or older player, and the motion related to the angles of the lower legs in the sagittal plan for junior high school students or older players. We also observed that pitcher gradually begin to achieve a skill throwing motion comparable to that of high school players from around the age group of late elementary school pupils, and approximately 50% of them manage to acquire it during their junior high school years. In addition, we observed that an equal proportion of players other than pitchers would also be able to acquire the correct throwing motion through a continuous approach with regard to quantity (number of pitches) and quality (pitching form). [ABSTRACT FROM AUTHOR]

In our study series, we analyzed characteristics regarding the throwing motions of 2,105 baseball players of various ages in different fielding positions (pitchers, catchers, infielders, outfielders) using a high-speed camera. In this paper, as Part 1, we report the analysis of characteristics regarding the sagittal trunk motions during the acceleration phase and ball release. As the result, we observed that it is possible to specify the pitcher's proper throwing motion as a goal for each age group, namely, the sagittal trunk motions for junior high school students or older players, as well as the ball release position and initial ball speed for late elementary school pupils older players. We also observed that although pitchers gradually begin to achieve a throwing motion comparable to that of high school players from around the age group of late elementary school pupils, they still require further growth, years of experience, and physical characteristics to achieve the same level as high school players, with regard to initial ball speed. [ABSTRACT FROM AUTHOR]

The purpose of this study is to biomechanically asses the physical function and the throwing motion of junior baseball players to prevent pitching injuries. The subjects were 158 male baseball players (11-18 years old). They were divided into three groups according to age: 61 little leaguers (LL group: 11-12 years old); 38 senior leaguers (SL group: 13-15 years old) and 59 high school players (HS group: 16-18 years old). Their physical function was evaluated by physical examinations such as range of motion test, muscular tightness test and joint loosening test. The three-dimensional throwing motion was measured by a motion capture system. In the throwing motion analysis, ball velocity, arm swing velocity, body movement velocity, landing force of the lead leg and trunk twist were significantly increased in the higher age groups (p<0.01). The shoulder and elbow joint moments were not different among the three groups. Since the shoulder and elbow joint loads caused by the throwing motion of the adolescent LL group seem to be almost the same as those in the higher age groups, pitching instructions and pitch count limitations are important to avoid upper extremity injuries. [ABSTRACT FROM AUTHOR]

The purpose of the present study is to demonstrate the correlation between the force applied to a ball and the joint motion of the hip, trunk, shoulder and elbow in adolescent baseball players. The subjects were 15 adolescent baseball players (13.7±0.8 yrs) and 15 college-age baseball players (22.1±1.5). Pitching motion images were captured by three high-speed cameras, and 3D analysis established by the direct leaner translation method was performed to obtain the angles and the angular velocity of each joint, as well as the acceleration of the wrist toward the target at ball release (Acc). In the adolescent players, a significant linear correlation was found between Acc and trunk rotation angle (r=-0.59), elbow extension angle (r=-0.75), shoulder internal rotation velocity (r=-0.76) and elbow extension velocity (r=-0.61). In the college-age players, a significant linear correlation was found between Acc and hip adduction velocity (r=-0.51) and elbow extension velocity (r=-0.61). The finding indicates that adolescent players may depend more on the upper extremity motion than the hip joint motion when pitching. Coaches and athletic trainers may need to focus on the hip joint motion in order to prevent pitching injuries among adolescent baseball players. [ABSTRACT FROM AUTHOR]

This study examined short-term effects of the all-fours posterior stretching technique for posterior shoulder tightness (PST) in high school baseball players. In this IRB-approved, single-blinded, cluster randomized controlled trial, we included 64 high school baseball players who were randomly allocated to the all-fours posterior stretch (APS) group or the internal rotational stretch (IRS) groups. We measured the range of shoulder motions in horizontal adduction, internal/external rotation at 90° abduction, and the total rotational arc. Both groups demonstrated an improved range of motion and no significant differences were detected between the groups. The results suggested that the APS technique is as effective as the IRS in preventing and reducing PST. A potential advantage of the APS would be the limited chance of inducing pain as compared with the IRS. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the morphology of rotator cuff muscles and shoulder isokinetic strength in adolescent baseball players. Junior high school baseball players were divided into a skilled group (SG, 6 players) and an unskilled group (USG, 6 players), according to their baseball history. The maximal anatomical cross-sectional area, and the volume of the rotator cuff muscles (supraspinatus, external rotators: infraspinatus and teres minor, and subscapularis) were mesured on both sides of their shoulders using magnetic resonance imaging. In addition, isokinetic shoulder internal and external rotation strength (180 and 300°/sec) were measured with the shoulder abducted 90° and the elbow flexed 90° on both sides. The external/internal strength ratio was also calculated. The paired and unpaired t-tests were used to analyze the difference between the throwing and nonthrowing sides and between both groups, respectively. Although the maximal cross-sectional area and the volume of each muscle in the SG tended to be greater than those in the USG on both sides of the shoulder, both groups showed significantly greater subscapularis on the throwing side, regardless of their baseball history. Concerning the shoulder strength and the strength ratio, there were no significant differences between the throwing and nonthrowing sides in each group, or between groups. However, there was a significant correlation between the maximal cross-sectional area of the external rotators and the shoulder external rotational strength (180 and 300°sec) on both sides of the shoulder. This study suggests that remakable characteristics of repetitive throwing activities were not found in the morpholgy of the rotator cuff muscles and the shoulder rotation strength in junior high school baseball players. [ABSTRACT FROM AUTHOR]

This study aimed to develop the system of onset prediction for throwing shoulder injury and evaluate its short-term effects. This system provided two parameters for every player. One was the probability of future onset of throwing shoulder injury. The other was the risk factors possessed by the players. Every player was able to know the risk of onset and the tailor-made methods for preventing injury. In the first year we developed this system and in the second year we introduced this system to a collegiate baseball team. We investigated the motivation for prevention and the prevalence of injury. As a result, 96% of the players increased their motivation for the prevention and the prevalence of injury decreased. This system was useful for field players to predict and prevent throwing shoulder injury. [ABSTRACT FROM AUTHOR]

Objective : The aim of this study was to investigate elbow injuries in high school baseball players. Methods : Seventy-one high school baseball players, aged from 15 to 17 years (mean :16 years), underwent a medical examination after the fall baseball season had ended. Questionnaire and physical examination were performed. Ultrasonography was used to assess the medial elbow laxity. Medial elbow instability was defined as an increase of 2.2mm or more in the medial joint space or lateral shift of the proximal ulna on the throwing side, compared to the non-throwing side. Diagnosis of medial collateral ligament injury (MCL injury) was based on elbow pain, positive milking test, and positive ultrasonographic medial elbow instability. Diagnosis of ulnar neuritis was based on positive findings of either muscle weakness or sensory changes in the ulnar nerve among subjects having difficulty in throwing due to elbow pain or numbness of little and ring fingers. Results : During a prior season, 32 subjects (25%) had experienced elbow pain, 3 (4%) had experienced numbness of little and ring fingers, and 26 (37%) had difficulty in throwing due to elbow pain. At the medical examination, 8 subjects (11%) had elbow pain, no player had numbness, and 8(11%)had difficulty in throwing due to elbow pain. Seventeen subjects (24%) were positive for the milking test. Twelve subjects (17%) had ultrasonographic medial elbow instability. MCL injury was diagnosed in 3 subjects (4%). Ulnar neuritis was diagnosed in 6 subjects (8%). Discussion : Elbow pain and difficulty in throwing at the medical examination was correlated with the milking test. These suggest that the milking test is useful for the screening of elbow pain and difficulty in throwing. [ABSTRACT FROM AUTHOR]

There have been a number of reports of muscle strength in the shoulders of high school baseball players, especially reports of rotation motion (internal and external rotation). This study had two purposes : one was to investigate standard muscle strength in first abduction motion and the other was to compare muscle power between an intact and an injured shoulder. We used orthopaedic tests (SSP test, ISP test, Jobe test impingement test), measured the range of motion for internal and external rotation of the shoulder, and measured muscle strength of the shoulder in first abduction motion using the BIODEX system 3. The maximum torque of first abduction motion was 36.5±4.8N-m for the pain group and 36.1±4.2N-m for the non-pain group. There was no statistically significant difference. This indicates that strength of the shoulder in first abduction motion was not affected by a shoulder disorder. The average muscle strength in first abduction motion for high school baseball players was 10.1±2.0%(kg). This data showed that muscle strength per weight in first abduction in high school baseball players was about 10% (kg) of weight, so that this data was available for sports medical examinations. [ABSTRACT FROM AUTHOR]

The purpose of the present study was to demonstrate the correlation between MER during throwing and each range of motion (ROM) of the shoulder complex, which consist of external rotation of glenohumeral joint and posterior tipping of the scapula in baseball players. The subjects were 19 collegiate baseball players. A three-dimensional analysis was performed to obtain the MER. The ROM of the external rotation of the shoulder complex (ER-ROM), ROM of the external rotation of the glenohumeral joint (GHE), and ROM of the posterior tipping of the scapula (SPT) were also passively measured. The mean (± SD) value of the MER was 150 ± 10°. The mean (± SD) values of the ER-ROM, GHE, and SPT were 135 ± 12°, 89 &plumsn; 12°, and 32 &plumsn; 7° respectively. Significant linear correlations were found between SPT and MER (r = 0.48), ER-ROM (r = 0.65). No significant correlations were found between GHE and MER and ER-ROM. The finding may indicate the importance of scapula motion more than glenohumeral joint motion for MER and ROM of the shoulder complex. [ABSTRACT FROM AUTHOR]

This study aimed to clarify the change of the proximal humeral epiphysis in youth baseball players comparing the throwing and non throwing arm in X-ray findings. In youth baseball shoulders, repeated throwing stress affected the proximal humeral epiphysis which demonstrated widening and disturbance of mineralization. About 0.5mm widening was observed in the dominant shoulder without shoulder pain. The regulation of pitch count is required at this age to avoid further injuries. [ABSTRACT FROM AUTHOR]

In this study, we analyzed ball release and stepping action employing a high speed camera system. The subjects were 1,033 baseball players in elementary school to university, and the purpose of this study was to evaluate the effectiveness of ZERO-MASHITANAGE, which was developed for beginners, from a biomechanical point of view. Initial ball speeds for usual- and ZERO-MASHITANAGE were 97.9 ± 16.2 and 87.1 ± 13.4 km/h, respectively, being significantly lower in the latter(p<0.001) . This is related to reduced load on the landing foot due to a skipped stepping action and a significant decrease in the stepping width in the latter(p<0.001) . It was also shown that the ball projection angle of the usual- and ZERO-MASHITANAGE were 27.0 ± 12.0° and 14.9 ± 12.8° , respectively, being significantly lower in the latter (p<0.001) . There was a strong positive correlation between the height of ball release from the ground and the ball projection angle in ZERO-MASHITANAGE (r = 0.803, n = 1.033, p<0.001) . The decrease in the ball projection angle in ZERO-MASHITANAGE was suggested to be due to a significant decrease in the height of ball release from the ground due to the throwing posture(p<0.001) , with the trunk side flexion closer to the landing foot. In progressing from ZERO-MASHITANAGE, appropriate coaching of more difficult stepping actions of the landing foot and take-back action of the dominant hand, leading to usual-MASHITANAGE and usual throwing, is recommended as a training method to improve throwing ability and as a rehabilitation regimen for those with upper-extremity throwing injuries. [ABSTRACT FROM AUTHOR]

This study aimed to examine the causes of injuries by comparing the contents of practice in high school baseball teams in each region. 683 coaches of high school baseball teams in five different prefectures were selected as the subjects of this study, and the number of valid answers were 223(32.7%). The questionnaire provided to the subjects included a team profile as well as the contents of practice, and history of injuries in players. The 223 subjects were divided into two regions such as the Kanto region and Tohoku-Koshinetsu region by the annual amount of snow fall. The results revealed no significant difference in the length of regular practice time in school days between the regions: however, warm-up time in the Kanto region was significantly shorter than in the Tohoku-Koshinetsu region throughout one year (p<0.001) . Also, the practice time during the fall and winter season in the Tohoku-Koshinetsu region was significantly shorter than the time in the Kanto region (p<0.001). Moreover, the result shows that the injuries in the shoulder (28.7%). elbow (24.1%), and lower back (15.5%) were the most typical injuries in high school baseball players. However, it also showed that players in different regions tended to have different injuries in different body parts. For instance, players in the Kanto region tended to have injuries due to overuse such as chronic injuries in the lower back and ankles. On the other hands, players in the Tohoku-Koshinetsu region tended to hurt their hamstrings and quadriceps mainly as muscle strain. The possible reasons for this result are different circumstances such as the contents of practice, length of practice time. and different school systems because of the different weather and climate in each region. Therefore, guidance on injury prevention has to fit each region in order to be more effective in high school baseball players. [ABSTRACT FROM AUTHOR]

[Purpose] We investigated the differences in the range of motion of the shoulder between elementary school baseball players and football players. [Materials and Methods] We studied 31 elementary school baseball players (group B) and 32 football players (group F). Shoulder internal rotation and external rotation with the arm abducted 90° (2nd IR and ER), internal rotation with the arm flexed 90° (3rd IR), horizontal flexion (HF), and glenohumeral abduction (Abd.) were measured bilaterally. The measurements were compared between the dominant and non-dominant shoulders. The differences between the dominant and non-dominant shoulders were compared between group B and group F. [Results] In group B, 2nd IR, 2nd total rotation, 3rd IR, Abd. and HF in the dominant shoulders were statistically less than those in the non dominant shoulders. And 2nd ER in the dominant shoulders was slightly greater than that in the non-dominant shoulders. In group F, there was no statistical difference in all range of motions between the dominant shoulders and the non-dominant shoulders. Regarding the differences between the dominant and non-dominant shoulders, the differences in 2nd IR, 2nd total rotation, 3rd IR, Abd., and HF in group B were statistically greater than those in group F. [Conclusion] This study indicated that the decrease in the internal rotation in the dominant shoulders was characteristic of baseball players and already existed in elementary school baseball players. [ABSTRACT FROM AUTHOR]

In this study, we analyzed the characteristics of trunk(shoulder line)rotation movement during throwing motion in female university baseball players (FUBP) by comparing with male university baseball players (MUBP). As a result, we found that trunk rotation movement at the ball release phase in FUBP was inadequate in comparison with a high-speed pitcher in MUBP. We also found that the contribution of trunk rotation movement to the throwing ability in FUBP is inadequate in comparison with MUBP. Above all, we conclude that the throwing motion in FUBP mostly depends on the swing movement of the upper extremities. Excessive repetition of such throwing motion may induce throwing injuries in the upper extremities. [ABSTRACT FROM AUTHOR]

We measured the isokinetic peak torque of shoulder rotators in baseball players with elbow throwing disorders. Isokinetic shoulder rotational strength was evaluated in 4 groups of subjects as follows: control group: without throwing disorders (18), MCL group: with elbow medial collateral ligament injury (15), OA group: with elbow osteoarthrosis (8), and UND group: with elbow ulnar nerve disorder (11). Isokinetic: tests were performed concentrically internal and external rotation at 60 deg/sec for the throwing shoulders. Test results for 4 group comparisons of peak torque for the throwing shoulders demonstrated a significant difference in external rotator values between the control group and MCL group, UND group at shoulders. The MCL group and UND group had lower values compared with the control group. This is a characteristic finding baseball players with elbow throwing pain in the medial aspect. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate quantitatively and non-invasively the muscle recruitment of the rotator cuff muscles in baseball pitching using MR imaging. Five healthy baseball pitchers (Mean ± SD, age; 23.2 ± 1.3 yr; height: 171.8 ± 6.72cm; weight: 68.8 ± 5.4kg) participated in this study. Subjects threw 135 pitches from the hand-made pitcher's mound in 9 innings. T2-weighted images of rotator cuff muscles were obtained using a 1.5 Tesla superconducting imaging system with an E1 shoulder coil before and Immediately after baseball pitching. T2 relaxation times (T2) before and after pitching were calculated for the supraspinatus muscle, the shoulder external rotator muscle group (the infraspinatus muscle and teres minor muscle) and the subscapularis muscle. This study revealed that T2 values in all rotator cuff muscles tended to increase immediately after baseball pitching. T2 elevation would be associated with an exercise-induced increase in intramuscular water content and he limited to those muscles which were active during the exercise. In addition, greater mean force production during exercise translated into greater increases in T2 values for the active muscles. Judging from the relative T2 elevation immediately after pitching, the present study showed that there was personal equation among the muscles exhibiting the greatest T2 value after baseball pitching. [ABSTRACT FROM AUTHOR]

This study examines the muscle strength characteristics (maximum torques, maximum torque exertion angle and the amount of maximum work during flexion and extension) in baseball players with elbow osteoarthritis as compared to non-professional baseball players who do not have disorders of the elbow joint. The results revealed no significant difference in the maximum torques during flexion and extension. However, the maximum torque exertion angle and the amount of maximum work at the time of extension was a low value intentionally in those players in the osteoarthritis group. This is probably because when the extension stress in the elbow is decreased, the low value of the maximum torque exertion angle was processed by a smaller joint. In baseball players with osteoarthritis these results are indicative of sharp pain and discomfort at the end of the pitching action. [ABSTRACT FROM AUTHOR]