Baseball Performance Research Articles

The Effects of Core Training on High School Baseball Performance

The Effects of Core Training on High School Baseball Performance

Epidemiology, Treatment, and Performance-Based Outcomes in American Professional Baseball Players With Symptomatic Spondylolysis and Isthmic Spondylolisthesis

Background: Repetitive lumbar hyperextension and rotation during athletic activity affect the structural integrity of the lumbar spine. While many sports have been associated with an increased risk of developing a pars defect, few previous studies have systematically investigated spondylolysis and spondylolisthesis in professional baseball players. Purpose: To characterize the epidemiology and treatment of symptomatic lumbar spondylolysis and isthmic spondylolisthesis in American professional baseball players. We also sought to report the return-to-play (RTP) and performance-based outcomes associated with the diagnosis of a pars defect in this elite athlete population. Study Design: Descriptive epidemiology study. Methods: A retrospective cohort study was conducted among all Major and Minor League Baseball (MLB and MiLB, respectively) players who had low back pain and underwent lumbar spine imaging between 2011 and 2016. Players with radiological evidence of a pars defect (with or without listhesis) were included. Analyses were conducted to assess the association between player-specific characteristics and RTP time. Baseball performance metrics were also compared before and after the injury episode to determine whether there was an association between the diagnosis of a pars defect and diminished player performance. Results: During the study period of 6 MLB seasons, 272 professional baseball players had low back pain and underwent lumbar spine imaging. Overall, 75 of these athletes (27.6%) received a diagnosis of pars defect. All affected athletes except one (98.7%) successfully returned to professional baseball, with a median RTP time of 51 days. Players with spondylolisthesis returned to play faster than those with spondylolysis, MLB athletes returned faster than MiLB athletes, and position players returned faster than pitchers. Athletes with a diagnosed pars defect did not show a significant decline in performance after returning to competition after their injury episode. Conclusion: Lumbar pars defects were a common cause of low back pain in American professional baseball players. The vast majority of affected athletes were able to return to competition without demonstrating a significant decline in baseball performance.

The Relationship Between Functional Movement, Dynamic Stability, and Athletic Performance Assessments in Baseball and Softball Athletes.

Stapleton, DT, Boergers, RJ, Rodriguez, J, Green, G, Johnson, K, Williams, P, Leelum, N, Jackson, L, and Vallorosi, J. The relationship between functional movement, dynamic stability, and athletic performance assessments in baseball and softball athletes. J Strength Cond Res 35(12S): S42-S50, 2021-Despite recent popularity, the relationship between movement quality and measures of athletic performance remains inconclusive. This investigation sought to clarify the relationships between measures of movement quality and measures of athletic performance in baseball and softball athletes. Thirty-eight National Collegiate Athletic Association Division I baseball (n = 23; age 20.00 ± 1.38 years, lower-extremity [LE] limb length 93.91 ± 4.37, upper-extremity [UE] limb length 92.37 ± 4.48) and softball (n = 15; age 19.93 ± 1.28 years, LE limb length 89.43 ± 4.67, UE limb length 84.61 ± 4.39) athletes completed the Functional Movement Screen (FMS) and the Y Balance Test for the lower and upper extremities (YBTLQ and YBTUQ, respectively). Performance assessments were proagility (PA), vertical jump (VJ), and rotational medicine ball throw to the right and left (RMTR and RMTL, respectively). No significant correlations were seen between any of the composite scores of movement quality and athletic performance in baseball athletes; shoulder mobility was weakly correlated with PA (rs = 0.442, p = 0.035). Composite FMS was negatively correlated with RMTR (rs = -0.753) in softball athletes. In addition, in softball athletes, RMTR was negatively correlated with in-line lunge (rs = -0.544, p = 0.04), trunk stability push-up (rs = -0.761, p = 0.002), anterior YBTLQ reach (r = -0.628), and posterolateral YBTLQ reach (r = -0.683); VJ was correlated with posterolateral YBTLQ reach (r = 0.531) and superolateral (SL) YBTUQ reach (r = 0.591), and PA was negatively correlated with posterolateral YBTLQ (r = -0.60) and SL YBTUQ reach (r = -0.557). The differences in correlations of movement quality and athletic performance between baseball and softball athletes suggest movement quality influences performance differently in female athletes and male athletes.

Dynamic vision training transfers positively to batting practice performance among collegiate baseball batters

A growing body of evidence demonstrates visual, perceptual, and oculomotor abilities contribute to batting performance in baseball and there is interest in whether training such abilities can transfer positively to batting performance. The current study tested this question through a pre-registered, randomized, and placebo-controlled intervention, conducted with 24 collegiate baseball players at two NCAA Division 1 universities. Athletes were randomized to receive either dynamic vision training consisting of stroboscopic, anticipatory timing, and eye quickness drills, or placebo drills stylized after control procedures in previous vision therapy studies. Generalized near-transfer was tested via a digital visual-motor task battery (n = 20), while sports-specific intermediate and far transfer of training were evaluated through instrumented batting practice metrics (n = 14) and box score performance in NCAA-sanctioned games (n = 12), respectively. The effects of training group were tested on these outcome measures while controlling for covariates such as pre-training expectations and site. Participants averaged 8.50 hours of training with no significant group differences in training adherence, expectations, or baseline assessments. ANCOVA revealed no group differences in measures of visual-motor skills or NCAA game statistics. However, batting practice demonstrated significant improvements in launch angle (p = 0.002, Cohen’s d = 0.74) and hit distance (p < 0.001, Cohen’s d = 0.70) for the active training cohort relative to the placebo control. This controlled and pre-registered pilot study therefore provides preliminary evidence that vision training may improve batting practice performance, creating new opportunities for the transfer of skill training and warranting further study.

Behavioral Measures in a Cognitive-Motor Batting Task Explain Real Game Performance of Top Athletes.

Excellent athletic performance in baseball and softball batting is achieved through the momentary cognitive-motor processes. However, in previous studies, cognitive and motor processes are investigated separately. In this study, we focused on the difference in the time of swing onset (a delta onset) during a batting task where 17 elite female softball batters hit balls randomly thrown at two different speeds by pitchers. The delta onset included both cognitive and motor processes because the batters needed to anticipate the ball speed and discriminate their swing motion according to the time-to-contact. Then, we investigated the relationship between the delta onset and the batting outcomes of the batting task, and the relationship between the experimental outcomes and actual batting performance (batting average) over a season. We used path analysis to clarify the structure of the cognitive-motor processes and consequent performance. We found that the batters who had a larger delta onset attained superior batting outcomes (i.e., higher exit velocity and lower miss ratio) in the batting task, and these experimental outcomes explained 67% of the batting average in real games. On the other hand, the cognitive scores (judgement accuracy and rapidity) obtained from a button pressing task, where batters responded to a ball by pressing a button instead of actually swinging, explained only 34% of the batting average. Therefore, our model quantitatively describes the key cognitive-motor structure for athletes and can partially predict a batter's performance in real games. These findings suggest that it is important to employ both cognitive and motor processes in performing tasks, such as this batting task, to properly evaluate a batter's actual ability.

Learning and Applying a Function Over Distributions

We present a method for learning a function over distributions. The method is based on generalizing nonparametric kernel regression by using the earth mover’s distance as a metric for distribution space. The technique is applied to the problem of learning the dependence of pitcher performance in baseball on multidimensional pitch distributions that are controlled by the pitcher. The distributions are derived from sensor measurements that capture the physical properties of each pitch. Finding this dependence allows the recovery of optimal pitch frequencies for individual pitchers. This application is amenable to the use of signatures to represent the distributions and a whitening step is employed to account for the correlations and variances of the pitch variables. Cross validation is used to optimize the kernel smoothing parameter. A set of experiments demonstrates that the new method accurately predicts changes in pitcher performance in response to changes in pitch distribution and also outperforms an existing technique for this application.

Situational Underlying Value (SUV) – A Single Statistic for Individual Performance in Major League Baseball

Situational Underlying Value (SUV) – A Single Statistic for Individual Performance in Major League Baseball

The Impact of Prior Musculoskeletal Injury and Orthopaedic Surgery on Draft Position, Availability, and Performance in Major League Baseball: A Summative Analysis of 1,890 Predraft Players

Objectives:Despite the value to future coaches, franchise management, and medical personnel, little is known about the epidemiology of musculoskeletal injuries and surgeries and their future impact prior to the MLB draft. The purpose of this study was to determine the (1) epidemiology of all musculoskeletal injuries and surgeries for predraft MLB players; (2) risk of injury or surgery on draft position; (3) risk of injury or surgery on availability within the first two years; and (4) risk of injury or surgery on performance.Methods:A total of 1,890 medical records conducted by MLB team physicians prior to the draft were retrospectively reviewed from 2014 to 2018. Players were divided into three groups: non-injured (no musculoskeletal history), non-operative (previously injured but treated non-operatively), and operative (previous injury requiring surgery). Game statistics, including draft round, missed games, batting average (BA), and earned run average (ERA) for the first 2 seasons of MLB play were obtained for all available players, Players were matched for position, and confounders were analyzed for age, draft round using ANOVA analysis.Results:A total of 927 pitchers and 963 position players were evaluated, and 38.9% had no reported injury history, 48.6% reported injury but were treated non-operatively, and 12.4% were treated operatively. The most common pre-draft injuries were elbow tendonitis (n=312), UCL injury (n=212), and shoulder labral tear (n=76). The most common pre-draft treatments were physical therapy (922, 25.3%), UCL reconstruction (115, 3.2%), and fracture fixation (69, 1.9%). No difference was found between non-injured, non-operative, and operative groups in terms of draft position, games missed, and performance (BA for position players, p = 0.7246; ERA for pitchers, p=0.1956). After position matching, age and draft round were non-confounding.Conclusion:More than half of players entering the MLB report a musculoskeletal injury requiring treatment, with the most common pathology involves the shoulder and elbow. After position matching and analyzing for confounding factors like age and draft round, musculoskeletal history did not macroscopically impact draft position, short-term availability, or performance.

Kinematic Factors that Contribute to Batting Performance in Collegiate Baseball

Kinematic Factors that Contribute to Batting Performance in Collegiate Baseball

Epidemiology and Impact of Prior Musculoskeletal Injury and Orthopaedic Surgery on Draft Rank, Availability, and Short-term Performance in Major League Baseball: A Summary Analysis and Matched Cohort of 1890 Predraft Players.

Background:Despite the many reports of injury rates in Major League Baseball (MLB), little is known about the epidemiology or impact of prior musculoskeletal injuries and surgical procedures among players entering the MLB draft.Purpose:To determine the (1) epidemiology of all musculoskeletal injuries and surgical procedures among players entering the MLB draft, (2) impact of injury or surgery on draft rank, (3) impact of injury or surgery on availability within the first 2 years of play in the MLB, and (4) impact of injury or surgery on performance.Study Design:Cohort study; Level of evidence, 3.Methods:We retrospectively reviewed 1890 medical records that were completed by MLB team physicians as preparticipation physical assessment prior to the draft from 2014 to 2018. Players were divided into 3 groups: noninjured, nonoperative, and operative. Draft status, overall draft rank, missed games, batting average, and earned run average for the first 2 seasons of MLB play were obtained for all available players. Players across all 3 groups were compared with linear, logistic, and beta regression models, controlling for age, position, injury status, and draft rank. Unadjusted differences among groups were assessed with 1-way analysis of variance.Results:Overall, 750 position players and 1140 pitchers were included, of whom 22.8% had no reported injury history; 48.8% reported injury treated nonoperatively; and 28.5% were treated operatively. The most common predraft injuries were elbow tendinitis (n = 312), ulnar collateral ligament injury (n = 212), and shoulder labral tear (n = 76). The most common predraft treatments were physical therapy (n = 922), ulnar collateral ligament reconstruction (n = 115), and fracture fixation (n = 69). Of the 1890 players, 719 were drafted and played for at least 2 years. No difference was found among noninjured, nonoperative, and operative groups in terms of draft rank, games missed, or performance. Players with a nonoperative injury had a decreased odds ratio of being drafted (0.738; P = .017).Conclusion:More than half of the players entering the MLB reported a history of musculoskeletal injury requiring treatment, and the most commonly affected joints were the shoulder and elbow. Musculoskeletal history did not affect draft rank, short-term availability, or performance for MLB prospects.

Performance and Return to Sport After Hip Arthroscopic Surgery in Major League Baseball Players.

Background:Femoroacetabular impingement (FAI) is a common cause of hip pain that may lead to decreased performance in Major League Baseball (MLB) players.Purpose:To determine the (1) return-to-sport (RTS) rate in MLB players after hip arthroscopic surgery for FAI; (2) postoperative career length, innings pitched (IP) (pitchers), and plate appearances (PA) (position players); (3) preoperative and postoperative performance; and (4) postoperative performance compared with control players matched by position, age, years of experience, and performance.Study Design:Cohort study; Level of evidence, 3.Methods:MLB athletes who underwent hip arthroscopic surgery for FAI and matched controls were identified. Demographic and performance data were collected. RTS was defined as playing in at least 1 MLB game after surgery. Continuous variables of each group were compared using a 2-tailed paired-samples Student t test for normally distributed data. The chi-square test was used to analyze categorical data. The Bonferroni correction was used to control for multiple comparisons, with statistical significance defined by a P value of ≤.007.Results:A total of 50 players (57 surgeries) were analyzed (mean age, 30.4 ± 3.9 years; mean MLB experience at the time of surgery, 7.0 ± 4.6 years). Pitchers (31 surgeries; 54.4%) represented the largest proportion of players analyzed. Of these players, 42 (47 surgeries; 82.5%) were able to RTS at a mean of 8.3 ± 4.1 months. The overall 1-year MLB career survival rate of players undergoing FAI surgery was 78.9%. Players in the control group were in MLB a similar number of years (4.0 ± 2.9 years) to players who underwent surgery (3.3 ± 2.4 years) (P > .007). There was no significant decrease in IP or PA per season after surgery (P > .007). There was no significant difference in performance for pitchers and nonpitchers compared with matched controls after surgery (P > .007).Conclusion:The RTS rate for MLB athletes after hip arthroscopic surgery for FAI was high. There were similar IP, PA, and career lengths postoperatively compared with preoperatively and with matched controls. There was no significant difference in performance for pitchers and nonpitchers compared with matched controls after surgery.

Major League Baseball Pitching Performance After Tommy John Surgery and the Effect of Tear Characteristics, Technique, and Graft Type

Background: Return to play and player satisfaction have been quite high after ulnar collateral ligament reconstruction (UCLR); however, there has been little reported on how outcomes are affected by surgical technique, graft type, and tear characteristics. Purpose: To evaluate surgical techniques, graft type, and tear characteristics on Major League Baseball (MLB) performance after UCLR. Study Design: Cohort study; Level of evidence, 2. Methods: MLB pitchers who underwent primary UCLR at a single institution were included. Tear characteristics included tear location, tear grade, and acuity. Surgical technique and graft type were also collected. Pitching performance statistics, including earned run average (ERA), walks and hits per innings pitched (WHIP), innings pitched, and fastball velocity were evaluated 3 years before and after UCLR. Results: Forty-six MLB pitchers were identified as having primary UCLR. Return to play was 96%, with 82% returning to MLB play. Technique performed showed no difference in performance. As compared with pitchers with gracilis grafts, pitchers with palmaris grafts were younger (P = .043), played longer after surgery (P = .012), and returned to play at 100% (35 of 35) versus 82% (9 of 11, P = .010). When compared with pitchers with proximal tears, pitchers with distal tears pitched at higher velocity (93.0 vs 90.6 mph, P = .023) and had better performance before surgery (ERA, P = .003; WHIP, P = .021); however, those with proximal tears improved to match this performance and velocity after reconstruction. As compared with those having partial tears, pitchers with complete tears played longer after surgery (5.9 vs 4.0 years, P = .033), had a better ERA before injury (P = .041), and had better WHIP (P = .037) and strikeouts per 9 innings (P = .025) after reconstruction. Pitchers with chronic tears had a significant improvement in postoperative ERA, from 4.49 to 3.80 (P = .040). Conclusion: Technique performed and graft type used did not affect performance; however, pitchers with palmaris grafts returned at a higher rate than those with gracilis grafts. Distal tears occurred in pitchers with greater velocity and better performance before injury, yet pitchers with proximal tears matched this performance after reconstruction. Pitchers with complete tears played longer after reconstruction. Pitchers who had partial tears had worse performance before injury and after reconstruction, and those with chronic tears saw a significant improvement in ERA with reconstruction.

Functional movement screen score and baseball performance in Japanese high school baseball players after corrective exercises

In recent years, the Functional Movement Screen (FMS™) has been used for the prevention of disability. Some studies have reported that corrective exercise to improve FMS score is an effective method of preventing injuries (Bodden et al., 2015; Justin et al., 2017). However, measurement instrument to assess FMS™ are not available in high school's. The purpose of this research is to clarify the effectiveness of corrective exercises without specific FMS measurement instruments on FMS score, physical function, and throwing performance in high school baseball players. High school baseball players were randomly assigned to two groups; 37 in the training group and 34 in the control group. All subjects were evaluated for FMS score, eyes closed single leg stance time, subjective fatigue, as well as pitching ball speed and control at the beginning of the intervention and at 2-months follow-up. Baseball players in training group conducted the corrective exercises 4 times per week for 2 months. When comparing the 2 groups group, pitching ball control significantly decreased in the training group compared to prior to the intervention. After 2 months, deep squat, hurdle step, inline lunge, active straight-leg raise, trunk stability pushup, rotary stability, total score of FMS, and pitching ball control showed significant better results in the training group compared to the control group. Results of this study showed that corrective exercises improved asymmetries, trunk stability, movement pattern, proprioception, total FMS score, and pitching ball control without using special instruments following a 2-months training period. Corrective exercises to improve FMS are effective even in high school baseball players without using special measurement instruments.

The Hand-eye Coordination of Professional Baseball Players: The Relationship to Batting.

A visuomotor skill (eye-hand visual-motor reaction time [EH-VMRT]) important for baseball performance is described. Eye-hand visual-motor reaction time represents the integration of visual information, perceptually based decisions, and motor movements to accomplish a specific task. The speed at which this occurs depends on many factors, some visual, some perceptual, and some motor related. The purpose of this study was to describe the EH-VMRT ability and evaluate its relationship to the baseball batting performance of professional baseball players. A commercially available EH-VMRT system was used on 450 professional baseball players. Results were retrospectively compared with standard, career, plate discipline metrics. Statistically significant correlations were found between the EH-VMRT metrics and plate discipline batting metrics. Better EH-VMRT ability also correlated with longer service in, and likelihood to achieve, the major-league level. The better (top 20%) EH-VMRT group had three fewer at bats before gaining a walk (22% decrease), as well as swinging 10 to 12% less often at pitches outside the strike zone and 6 to 7% less often at pitches in the strike zone as compared with the bottom 20% group. In addition, EH-VMRT displays a threshold-like relationship with the ability to gain a walk. These results describe the EH-VMRT ability of professional baseball players and show a significant relationship between the EH-VMRT ability and batting performance. These results may suggest a possible role in player selection, indicating that batters with better EH-VMRT may be more likely to reach the major-league level and be more productive for their team. Further studies will be needed to demonstrate whether training better EH-VMRT results in improved batting performance.

Estimating the effect of plate discipline using a causal inference framework: an application of the G-computation algorithm

Abstract Offensive performance in baseball depends on a number of correlated factors: the pitches the batter faces, the batter’s choice to swing, and the batter’s hitting ability. Recently a renewed focus on the effect of plate discipline on batter performance has emerged. Plate discipline has traditionally been summarized as the proportion of pitches inside and outside of the strike zone a player swings at; however, there have been few metrics proposed to assess the effect of plate discipline directly on batters’ outcomes. In this paper, we focus on estimating a batter’s performance if he were able to adopt a different plate discipline. Because we wish to assess the effect of a counterfactual plate discipline, we use a potential outcome framework and show how the G-computation algorithm can be used to isolate the effect of plate discipline separately from a batter’s hitting ability or the types of pitches the batter faces. As an example, we implement our approach using data collected with the PITCHf/x system over the 2012–2014 seasons to identify the improvement Starlin Castro would expect to see in offensive performance were he able to adopt Andrew McCutchen’s plate discipline. We estimate that had Castro adopted McCutchen’s discipline his batting average, on-base percentage, and slugging percentage would have increased 0.017 (se = 0.004), 0.040 (se = 0.006), and 0.028 (se = 0.008), respectively.

Anthropometric and Performance Statistics Comparisons in Baseball Pitchers

Athletic ability, performance, and motor skills depend greatly on human proportionality. Practicing sports at a high level is associated with a person’s ability to meet the biomechanical demands of a particular sport or playing position. The ideal somatotype of athletes in different sports and within the same sport has been described. However, there is limited evidence regarding the association between the anthropometric characteristics, such as body weight (BW), body height (BH), and body fat % (BF%) of collegiate baseball pitchers and baseball performance statistics (PS). PURPOSE: To compare BW, BH, BF% and selected baseball-specific PS, such as earned run average (era), batting average against % (b/avg-a%), and strike-out per innings pitched for 9 innings (so/ip)*9 in NCAA Division I pitchers; to examine the relationship between BW, BH, BF% and baseball-specific PS. METHODS: During a 5-year period, 210 collegiate pitchers (age 19.7 + 1.2 yr; weight 92 + 8.2 kg) were assessed for body weight (BW), body height (BH), and body fat % (BF%). The following pitchers’ baseball statistics were collected: era, b/avg-a%, and (so/ip)*9. BW, BH, BF%, and PS were normalized to z-scores. Missing data were estimated from least squares prediction from non-missing variables. Forward multiple stepwise regression was used to evaluate the relative impact of BW, BH, and BF% on PS (JMP® Pro 13). RESULTS: BH is significantly correlated both with b/avg-a% (r=-0.18, p=0.0104) and era (r=0.22, p=0.0010). BW is significantly correlated with (so/ip)*9 (r=0.22, p=0.0016). BF% is significantly correlated with both era (r=-0.26, p=0.0001) and (so/ip)*9 (r=-0.14, p=0.0472). Strike-out per innings pitched for 9 innings was selected as the independent variable with the highest goodness of fit significantly correlating with BW (p=0.0004), BH (p=0.0004), and BF% (p=0.0022) with adjusted R2=0.12. CONCLUSIONS: The results indicate that BW, BH, and BF% of pitchers correlate with b/avg-a%, era, and (so/ip)*9. BW, BH, and BF% appeared to provide the greatest predictive power of (so/ip)*9. The selected anthropometric variables accounted for 12% of the variance in (so/ip)*9. Runs are usually scored by hits. Coaches and trainers want pitchers to prevent runs. Therefore, they may need to account for other factors besides BW, BH, and BF%.

Effect of Predraft Ulnar Collateral Ligament Reconstruction on Future Performance in Professional Baseball: A Matched Cohort Comparison

Background: In recent years, there has been a dramatic rise in the annual number of ulnar collateral ligament (UCL) reconstructions performed in amateur baseball pitchers. Accordingly, increasing numbers of players are entering professional baseball having already undergone the procedure; however, the effect of prior UCL reconstruction on future success remains unknown. Purpose: (1) To provide an epidemiologic report on baseball players who undergo UCL reconstruction before being selected in the Major League Baseball (MLB) Draft, (2) to define the outcomes in terms of statistical performance, and (3) to compare these results with those of matched controls (ie, non–UCL reconstruction). Study Design: Cohort study; Level of evidence, 3. Methods: The MLB Amateur Draft Database was queried to identify all drafted pitchers who underwent UCL reconstruction before being drafted. For each pitcher drafted from 2005 to 2014 with prior UCL reconstruction, 3 healthy controls with no history of elbow surgery were randomly identified for matched analysis. A number of demographic and performance comparisons were made between these groups. Results: A total of 345 pitchers met inclusion criteria. The annual number of pitchers undergoing predraft UCL reconstructions rose steadily from 2005 to 2016 (P < .001). For matched control analysis, 252 pitchers with a UCL reconstruction and a minimum 2-year follow-up (drafted between 2005 and 2014) were matched to 756 controls (non–UCL reconstruction). As compared with the non–UCL reconstruction group, pitchers who underwent predraft UCL reconstruction reached the MLB level with greater frequency (20% vs 12%, P = .003), and their MLB statistical performances were similar for all measures. Compared with all other pitchers drafted during that period, players who had a predraft UCL reconstruction demonstrated an increased likelihood of reaching progressive levels of play (Full Season A, AA, and MLB) within a given time frame (P < .05 for all). Conclusion: The number of UCL reconstructions performed in amateur baseball players before the draft increased year over year for the entire study period. Professional pitchers who underwent UCL reconstruction as amateurs appear to perform at least as well as, if not better than, matched controls without elbow surgery.

Exploring ethnic identity perceptions of Hyun-Jin Ryu’s Korean American fans

The purpose of this study was to understand the lived experiences of Korean American fans of the Los Angeles Dodgers’ Korean pitcher Hyun-Jin Ryu. Two research questions were developed to guide the study: (a) How are participants’ ethnic identity perceptions as Korean Americans intertwined with their fanship to Hyun-Jin Ryu? and (b) How are participants’ lived experiences intertwined with their fanship to Ryu? The study focused on the details of how fans perceived their ethnic identity in relation to Ryu’s performance and presence in Major League Baseball. Findings revealed that fans initially became involved due to their ethnic ties to Ryu and remained as fans because they felt connected to the motherland of Korea. Fans individually identified with Ryu through the perceived minority status of being Korean American in the US. Fans experienced vicarious satisfaction as they felt Ryu broke racial, ethnic, and gender stereotypes through his body image and physical performance. Consequently, they developed Korean pride when Ryu performed well. This study extends Tajfel and Turner’s social identity theory and Phinney’s concept of ethnic identity to examine fanship to a specific player rather than a team.

Sensorimotor abilities predict on-field performance in professional baseball

Baseball players must be able to see and react in an instant, yet it is hotly debated whether superior performance is associated with superior sensorimotor abilities. In this study, we compare sensorimotor abilities, measured through 8 psychomotor tasks comprising the Nike Sensory Station assessment battery, and game statistics in a sample of 252 professional baseball players to evaluate the links between sensorimotor skills and on-field performance. For this purpose, we develop a series of Bayesian hierarchical latent variable models enabling us to compare statistics across professional baseball leagues. Within this framework, we find that sensorimotor abilities are significant predictors of on-base percentage, walk rate and strikeout rate, accounting for age, position, and league. We find no such relationship for either slugging percentage or fielder-independent pitching. The pattern of results suggests performance contributions from both visual-sensory and visual-motor abilities and indicates that sensorimotor screenings may be useful for player scouting.

Transfer of Training from Virtual to Real Baseball Batting.

The use of virtual environments (VE) for training perceptual-motors skills in sports continues to be a rapidly growing area. However, there is a dearth of research that has examined whether training in sports simulation transfers to the real task. In this study, the transfer of perceptual-motor skills trained in an adaptive baseball batting VE to real baseball performance was investigated. Eighty participants were assigned equally to groups undertaking adaptive hitting training in the VE, extra sessions of batting practice in the VE, extra sessions of real batting practice, and a control condition involving no additional training to the players’ regular practice. Training involved two 45 min sessions per week for 6 weeks. Performance on a batting test in the VE, in an on-field test of batting, and on a pitch recognition test was measured pre- and post-training. League batting statistics in the season following training and the highest level of competition reached in the following 5 years were also analyzed. For the majority of performance measures, the adaptive VE training group showed a significantly greater improvement from pre-post training as compared to the other groups. In addition, players in this group had superior batting statistics in league play and reached higher levels of competition. Training in a VE can be used to improve real, on-field performance especially when designers take advantage of simulation to provide training methods (e.g., adaptive training) that do not simply recreate the real training situation.