In-Game Workload Demands of Position Players in Major League Baseball.

BACKGROUND: Athletes who are well prepared for the physical demands of competition are less susceptible to injury. Defining and then preparing athletes for these in-game demands is critical to athlete health and performance. The injury burden within Major League Baseball (MLB) is significant and differs by position. Despite its importance, the workload demands have not been described for position players in MLB. HYPOTHESIS: That running demands would be significantly higher for outfielders, followed by infielders, and catchers, respectively, while batting and baserunning metrics would be similar across positions. STUDY DESIGN: Cohort study. LEVEL OF EVIDENCE: Level 3. METHODS: Total and high-speed running distance (>75% Vmax), high-speed running count, hard accelerations (>2.78 m/s/s), defensive and baserunning minutes, total and hard throws (>75% max), and bat swing counts were calculated from Statcast data. Players with 100 games or more in the 2018 season (n = 126) were included for analysis. RESULTS: All offensive and baserunning metrics were similar across positions; however, significant positional differences were observed for defensive and overall workload metrics. High-speed running was highest among outfielders (F1,7 = 27.1, P < 0.01), followed by infielders, then catchers. Hard accelerations (F1,7 = 12.9, P < 0.01) were highest among first basemen, then outfielders, remaining infielders, and catchers. Total throws (F1,7 = 17.7, P < 0.01) were highest among middle infielders. Hard throws (P < 0.01) were highest among shortstops and third basemen. CONCLUSION: In-game workloads differ significantly by defensive position in MLB. These differences in running, throwing, and hitting volumes have significant implications for physical preparation and injury return-to-play progressions to optimize performance and minimize injury and reinjury risk for these athletes. CLINICAL RELEVANCE: These data provide insight into how best to prepare athletes of different positions for the demands of the game both in terms of preseason preparation as well as return-to-play benchmarks following injury. These data should also serve as a platform for future research into the relationship between workload and injury among professional baseball players.

National survey of Australian cardiac rehabilitation programmes: does current exercise programming adhere to evidence-based guidelines and best practice?

Objectives: The efficacy of exercise-based cardiac rehabilitation (CR) for patient outcomes is well established, with better outcomes when delivery meets recommended guidelines. The aim of this study was to assess how well Australian practice aligns with national CR guidelines for exercise assessment and prescription. Method: This cross-sectional online survey was distributed to all 475 publicly listed CR services in Australia and consisted of four sections: (1) Programme and client demographics, (2) aerobic exercise characteristics, (3) resistance exercise characteristics and (4) pre-exercise assessment, exercise testing and progression. Results: In total, 228 (54%) survey responses were received. Only three of five Australian guideline recommendations were consistently reported to be followed in current CR programmes: assessment of physical function prior to exercise (91%), prescription of light-moderate exercise intensity (76%) and review of referring physician results (75%). Remaining guidelines were commonly not implemented. For example, only 58% of services reported an initial assessment of resting ECG/heart rate, and only 58% reported the concurrent prescription of both aerobic and resistance exercise, which may have been influenced by equipment availability (p<0.05). Exercise-specific assessments such as muscular strength (18%) and aerobic fitness (13%) were uncommonly reported, although both were more frequent in metropolitan services (p<0.05) or when an exercise physiologist was present (p<0.05). Conclusions: Clinically relevant deficits in national CR guideline implementation are common, potentially influenced by location, exercise supervisor and equipment availability. Key deficiencies include the lack of concurrent aerobic and resistance exercise prescription and infrequent assessment of important physiological outcomes including resting heart rate, muscular strength and aerobic fitness.

Differences in Glenohumeral Range of Motion and Humeral Torsion Between Right-Handed and Left-Handed Professional Baseball Pitchers.

BACKGROUND: Elite pitchers have demonstrated significant differences in glenohumeral range of motion and humeral torsion compared with the nonthrowing population. Furthermore, abnormal shoulder range of motion measurements have been associated with different injury risks and challenges in assessing rehabilitation progress. Variations in range of motion and torsion due to handedness in the asymptomatic professional population have yet to be investigated in the literature. HYPOTHESIS: No significant differences in glenohumeral range of motion and humeral torsion would exist between asymptomatic right- and left-handed professional pitchers. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: 217 Major League Baseball pitchers from a single organization were evaluated over a 7-year period between 2013 and 2020. Range of motion was measured with a standard goniometer. Ultrasound scanning was used to determine neutral position of the shoulder, and the degree of humeral torsion was measured with a goniometer. RESULTS: Right-handed pitchers demonstrated significantly greater values of glenohumeral external rotation (118.5° vs 112.7°; P < .001) in their throwing arms compared with their left-handed counterparts. Right-handed pitchers also showed greater values of glenohumeral internal rotation deficit (13.9° vs 4.8°; P < .001) and side-to-side differences in humeral retrotorsion (-23.1° vs -2.2°; P < .001). Left-handed pitchers demonstrated significantly greater flexion deficits in the throwing arm compared with their right-handed counterparts (7.5° vs 0.0°; P < .001). CONCLUSION: In the throwing arm, right-handed pitchers demonstrated significantly greater measures of external rotation, glenohumeral internal rotation deficit, and humeral retrotorsion compared with left-handed counterparts. Furthermore, right-handed pitchers demonstrated a significant side-to-side difference in retrotorsion, whereas left-handed pitchers did not. However, left-handed pitchers demonstrated a side-to-side shoulder flexion deficit that was not present in the cohort of right-handed pitchers. The correlation between humeral retrotorsion and increased external rotation indicates that osseous adaptations may play a role in range of motion differences associated with handedness. Additionally, these findings may explain observed differences in several throwing metrics between right- and left-handed pitchers. Knowledge of these differences can inform rehabilitation programs and shoulder maintenance regimens.

Bayesian hierarchical modelling of basketball tracking data - a case study of spatial entropy and spatial effectiveness.

Spatio-temporal data in sport is increasing rapidly, however suitable statistical methods for analysing this data are underdeveloped. The current study establishes the need for spatial statistical methods, propose a Bayesian hierarchical model as an appropriate method for comparing spatial variables, and test this model across three spatial scales. The need for spatial statistical methods was established through the identification of spatial autocorrelation. This necessitated the use of a Bayesian hierarchical model to test for an association between spatial ball movement entropy and spatial effectiveness. Posterior distribution results showed a generally positive association such that increases in entropy were associated with increases in effectiveness. The strength and confidence of the associations were impacted by the spatial scale, with the 6 × 6 grid showing the most conclusive evidence of a positive relationship; the 4 × 4 grid was mostly positive, however with a large variation; and finally, the basket-centric scale results were less conclusive. The results of the current study demonstrate the suitability of a Bayesian hierarchical model for testing for associations or differences between spatial variables. With the increase in spatial analyses in sport, this study presents an appropriate statistical method for dealing with complex problems associated with spatial analyses.

Cluster randomised control trial for cricket injury prevention programme (CIPP): a protocol paper.

BACKGROUND: Injury prevention programmes (IPPs) are effective in reducing injuries among adolescent team sports. However, there is no validated cricket-specific IPP despite the high incidence of musculoskeletal injuries among amateur cricketers. OBJECTIVES: To evaluate whether a cricket injury prevention programme (CIPP) as a pretraining warm-up or post-training cool-down can reduce injury rates in amateur cricket players. METHODS: CIPP is a cluster randomised controlled trial which includes 36 male amateur club teams having cricket players aged 14-40 years to be randomly assigned to three study arms: warm-up, cool-down and control (n=12 teams, 136 players in each arm). The intervention groups will perform 15 min CIPP either as a pretraining warm-up or a post-training cool-down. OUTCOME MEASURES: The primary outcome measure will be injury incidence per 1000 player hours and the secondary outcome measures will be whether IPP as a warm-up is better than IPP as a cool-down, and the adherence to the intervention. TRIAL REGISTRATION NUMBER: ACTRN 1261700047039.

Physical Activity Assessment in Clinical Studies of Substance Use Disorder.

The therapeutic effect of exercise in promoting mental health is well known, and there is a growing body of evidence for incorporating physical activity-based interventions in the management of substance use disorders (SUD). A particular challenge in this area is a lack of standardized testing protocols between studies and clear descriptive statistics on the capacity of the SUD patient to perform exercise. Therefore, an essential starting point for new studies that seek to incorporate exercise into usual care therapy for SUD is an appropriate suite of baseline fitness assessments that include measures of aerobic capacity as well as muscular strength and/or endurance. We present here the methods and notes of our recent experiences in implementing baseline fitness testing of a patient population undergoing in-patient treatment for SUD. The tests described here have been adapted from freely available standardized tests that were developed for implementation with the general population. It is hoped that these experiences aid in the development of patient-specific physical activity programs that assist in the management of SUD.

Does Strength-Promoting Exercise Confer Unique Health Benefits? A Pooled Analysis of Data on 11 Population Cohorts With All-Cause, Cancer, and Cardiovascular Mortality Endpoints.

Public health guidance includes recommendations to engage in strength-promoting exercise (SPE), but there is little evidence on its links with mortality. Using data from the Health Survey for England and the Scottish Health Survey from 1994-2008, we examined the associations between SPE (gym-based and own-body-weight strength activities) and all-cause, cancer, and cardiovascular disease mortality. Multivariable-adjusted Cox regression was used to examine the associations between SPE (any, low-/high-volume, and adherence to the SPE guideline (≥2 sessions/week)) and mortality. The core sample comprised 80,306 adults aged ≥30 years, corresponding to 5,763 any-cause deaths (736,463 person-years). Following exclusions for prevalent disease/events occurring in the first 24 months, participation in any SPE was favorably associated with all-cause (hazard ratio (HR) = 0.77, 95% confidence interval (CI): 0.69, 0.87) and cancer (HR = 0.69, 95% CI: 0.56, 0.86) mortality. Adhering only to the SPE guideline was associated with all-cause (HR = 0.79, 95% CI: 0.66, 0.94) and cancer (HR = 0.66, 95% CI: 0.48, 0.92) mortality; adhering only to the aerobic activity guideline (equivalent to 150 minutes/week of moderate-intensity activity) was associated with all-cause (HR = 0.84, 95% CI: 0.78, 0.90) and cardiovascular disease (HR = 0.78, 95% CI: 0.68, 0.90) mortality. Adherence to both guidelines was associated with all-cause (HR = 0.71, 95% CI: 0.57, 0.87) and cancer (HR = 0.70, 95% CI: 0.50, 0.98) mortality. Our results support promoting adherence to the strength exercise guidelines over and above the generic physical activity targets.

Associations between multiple indicators of socio-economic status and muscle-strengthening activity participation in a nationally representative population sample of Australian adults.

BACKGROUND: Muscle-strengthening activity (MSA) (e.g. weight training), confers unique health benefits. While socioeconomic status (SES) correlates with leisure time physical activity, little is known about its relation with MSA. METHODS: Cross-sectional study of a representative sample of 8993 Australian adults (>18years) who participated in the National Nutrition and Physical Activity Survey 2011-12. Information was collected on SES (income, education, socio-economic disadvantage and remoteness) and MSA participation. RESULTS: 17.9% (CI: 16.8-19.0) met the national guidelines for MSA (≥2 sessions/week). Men and younger adults (<35years) met MSA guidelines more than females (19.7%; CI: 18.3-21.1% vs 16.1%; CI: 14.6-17.6%; p<0.001) and older adults respectively (25.0%; CI: 22.4-27.7% vs 10.4%; CI: 8.9-11.8%; p<0.001). All SES indicators were associated with meeting the guidelines in unadjusted analyses. When adjusting for total physical activity and mutually adjusting for each socioeconomic indicator only remoteness (OR for city vs rural=1.65; CI: 1.17-2.32; p<0.001) was associated with MSA participation (education OR=1.09 for high vs low; CI: 0.80-1.47, p=0.748; income OR=1.31 for Q5 vs Q1, CI: 0.93-1.85, p=0.328; social disadvantage OR=1.04 for v.high vs v.low, CI: 0.76-1.43, p=0.855). These associations were further attenuated when adjusting for BMI, smoking status and self-rated health. CONCLUSION: Remoteness, and to a lesser degree, education, income and social disadvantage, were independently associated with MSA participation. Public health interventions should improve access to strength training facilities, and/or increase home-based muscle-strengthening activity in remote areas.

The effect of progressive resistance training on aerobic fitness and strength in adults with coronary heart disease: A systematic review and meta-analysis of randomised controlled trials.

Design We aimed to evaluate the effect of progressive resistance training on cardiorespiratory fitness and muscular strength in coronary heart disease, when compared to control or aerobic training, and when combined with aerobic training. Secondary aims were to evaluate the safety and efficacy of progressive resistance training on other physiological and clinical outcomes. Methods and results Electronic databases were searched from inception until July 2016. Designs included progressive resistance training vs control, progressive resistance training vs aerobic training, and combined training vs aerobic training. From 268,778 titles, 34 studies were included (1940 participants; 71.9% male; age 60 ± 7 years). Progressive resistance training was more effective than control for lower (standardized mean difference 0.57, 95% confidence interval (0.17-0.96)) and upper (1.43 (0.73-2.13)) body strength. Aerobic fitness improved similarly after progressive resistance training (16.9%) or aerobic training (21.0%); (standardized mean difference -0.13, 95% confidence interval (-0.35-0.08)). Combined training was more effective than aerobic training for aerobic fitness (0.21 (0.09-0.34), lower (0.62 (0.32-0.92)) and upper (0.51 (0.27-0.74)) body strength. Twenty studies reported adverse event information, with five reporting 64 cardiovascular complications, 63 during aerobic training. Conclusion Isolated progressive resistance training resulted in an increase in lower and upper body strength, and improved aerobic fitness to a similar degree as aerobic training in coronary heart disease cohorts. Importantly, when progressive resistance training was added to aerobic training, effects on both fitness and strength were enhanced compared to aerobic training alone. Reporting of adverse events was poor, and clinical gaps were identified for women, older adults, high intensity progressive resistance training and long-term outcomes, warranting future trials to confirm safety and effectiveness.

Strength and Power Correlates of Throwing Velocity on Subelite Male Cricket Players.

Throwing velocity is an important aspect of fielding in cricket to affect run-outs and reduce the opponent's run-scoring opportunities. Although a relationship between strength and/or power and throwing velocity has been well established in baseball, water polo, and European handball, it has not been adequately explored in cricket. Consequently, this study aimed to determine the relationship between measures of strength and/or power and throwing velocity in cricket players. Seventeen male cricket players (mean ± SD; age, 21.1 ± 1.6 years; height, 1.79 ± 0.06 m; weight, 79.8 ± 6.4 kg) from an elite athlete program were tested for maximal throwing velocity from the stretch position and after a 3-meter shuffle. They were also assessed for strength and power using a range of different measures. Throwing velocity from the stretch position (30.5 ± 2.4 m·s) was significantly related to dominant leg lateral-to-medial jump (LMJ) distance (r = 0.71; p < 0.01), dominant shoulder internal rotation (IR) strength (r = 0.55; p ≤ 0.05), and dominant (r = 0.73; p < 0.01) and nondominant (r = 0.54; p ≤ 0.05) medicine ball rotation (MB Rot) throw velocity and medicine ball chest pass (MB CP) distance (r = 0.67; p < 0.01). A nonsignificant trend was observed for vertical jump (VJ) height (p = 0.06), whereas no significant relationships were observed for nondominant LMJ distance (p = 0.97), nondominant shoulder IR strength (p = 0.80), 1 repetition maximum (RM) squat strength (p = 0.57), 1RM bench press strength (p = 0.90), height (p = 0.33), or weight (p = 0.29). Multiple regression analysis revealed that dominant MB Rot and MB CP explained 66% of the variance. The results were similar for velocity after a shuffle step (31.8 ± 2.1 m·s); however, VJ height reached statistical significance (r = 0.51; p ≤ 0.05). The multiple regression was also similar with MB Rot and MB CP explaining 70% of the variance. The cricketers in this study threw with greater velocity than elite junior and subelite senior cricketers but with lower velocities than elite senior cricketers and collegiate level and professional baseball players. This is the first study to demonstrate a link between strength and/or power and throwing velocity in cricket players and highlight the importance of power development as it relates to throwing velocity. Exercises that more closely simulated the speed (body weight jumps and medicine ball throws) or movement pattern (shoulder IR) of overhead throwing were greater predictors of throwing velocity. Strength and conditioning staff should assess and develop power to enhance throwing performance in cricket players. Exercises with greater movement and speed specificity to throwing should be used in preference over exercises that are slower and have less movement specificity to the throwing motion. Cricket players should engage in power training to bridge the gap in performance between them and baseball players.

The Efficacy of Injury Prevention Programs in Adolescent Team Sports: A Meta-analysis.

BACKGROUND: Intensive sport participation in childhood and adolescence is an established cause of acute and overuse injury. Interventions and programs designed to prevent such injuries are important in reducing individual and societal costs associated with treatment and recovery. Likewise, they help to maintain the accrual of positive outcomes from participation, such as cardiovascular health and skill development. To date, several studies have individually tested the effectiveness of injury prevention programs (IPPs). PURPOSE: To determine the overall efficacy of structured multifaceted IPPs containing a combination of warm-up, neuromuscular strength, or proprioception training, targeting injury reduction rates according to risk exposure time in adolescent team sport contexts. STUDY DESIGN: Systematic review and meta-analysis. METHODS: With established inclusion criteria, studies were searched in the following databases: Cochrane Central Register of Controlled Trials, MEDLINE, SPORTDiscus, Web of Science, EMBASE, CINAHL, and AusSportMed. The keyword search terms (including derivations) included the following: adolescents, sports, athletic injuries, prevention/warm-up programs. Eligible studies were then pooled for meta-analysis with an invariance random-effects model, with injury rate ratio (IRR) as the primary outcome. Heterogeneity among studies and publication bias were tested, and subgroup analysis examined heterogeneity sources. RESULTS: Across 10 studies, including 9 randomized controlled trials, a pooled overall point estimate yielded an IRR of 0.60 (95% CI = 0.48-0.75; a 40% reduction) while accounting for hours of risk exposure. Publication bias assessment suggested an 8% reduction in the estimate (IRR = 0.68, 95% CI = 0.54-0.84), and the prediction interval intimated that any study estimate could still fall between 0.33 and 1.48. Subgroup analyses identified no significant moderators, although possible influences may have been masked because of data constraints. CONCLUSION: Compared with normative practices or control, IPPs significantly reduced IRRs in adolescent team sport contexts. The underlying explanations for IPP efficacy remain to be accurately identified, although they potentially relate to IPP content and improvements in muscular strength, proprioceptive balance, and flexibility. CLINICAL RELEVANCE: Clinical practitioners (eg, orthopaedics, physical therapists) and sports practitioners (eg, strength and conditioners, coaches) can respectively recommend and implement IPPs similar to those examined to help reduce injury rates in adolescent team sports contexts.

THE LAUNCH WINDOW HYPOTHESIS AND THE SPEED-ACCURACY TRADE-OFF IN BASEBALL THROWING.

The speed-accuracy trade-off in throwing has been well described, but its cause is poorly understood. The popular impulse-variability hypothesis lacks relevance to throwing, while the launch window hypothesis has explanatory potential but has not been empirically tested. The current study therefore aimed to quantify the speed-accuracy trade-off and launch window during a throwing task at two different speeds. Nine elite junior baseball players (M age=19.6 yr.; M height=1.80 m; M weight=75.5 kg) threw 10 fastballs at 80 and 100% of maximal throwing speed (MTS) toward a 7 cm target from a distance of 20 m. A 3D motion analysis system measured ball speed and trajectory. A speed-accuracy trade-off occurred, mediated by increased vertical error. This can be attributed to the launch window, which was significantly smaller, particularly its vertical component, during 100% MTS. Maximal throwing speed correlated negatively with launch window size. The launch window hypothesis explained the observed speed-accuracy trade-off, providing a framework within which aspects of technique can be identified and altered to improve performance.

Position-specific anthropometry and throwing velocity of elite female water polo players.

This study was conducted with the following aims: (a) to describe the effect of playing position on anthropometrics and throwing velocity in elite female water polo players and (b) to observe any relationships between anthropometric parameters and throwing velocity. To achieve these aims, we analyzed a total of 46 female elite players (age: 22.5 ± 5.1 years; height: 172.0 ± 6.9 cm, body mass: 67.4 ± 7.5 kg) members of the top 4 teams of the Spanish Honour Division women league (21 offensive wings players, 17 center, and 8 goalkeepers). Wings were significantly shorter and had smaller arm spans than goalkeepers and center players. Goalkeepers demonstrated longer forearm lengths than wing and center players. No other significant differences were evident between positions in terms of anthropometric, strength, or throwing velocity variables The somatotype of the offensive wing players was mesomorphic, whereas centers were endomorph (classified as endomesomorphic). Height, arm span, muscular mass, biepicondylar breadth of the humerus, arm girth (relaxed and tensed), and forearm girth were related to throwing velocity. In conclusion, only a small number of anthropometric differences exist between players of different positions in elite female water polo. Shorter players with smaller arm spans may be better suited to the wings, whereas athletes with longer forearms may be better suited to the goalkeeper position. Taller, more muscular athletes with wider arm spans, broader humeri, and wider arms (relaxed and flexed) tended to throw with increased velocity. Trainers should focus on increasing the modifiable characteristics (muscle mass and arm girths) that contribute to throwing velocity in this population.

Shoulder proprioception is not related to throwing speed or accuracy in elite adolescent male baseball players.

Understanding factors that influence throwing speed and accuracy is critical to performance in baseball. Shoulder proprioception has been implicated in the injury risk of throwing athletes, but no such link has been established with performance outcomes. The purpose of this study was to describe any relationship between shoulder proprioception acuity and throwing speed or accuracy. Twenty healthy elite adolescent male baseball players (age, 19.6 ± 2.6 years), who had represented the state of New South Wales in the past 18 months, were assessed for bilateral active shoulder proprioception (shoulder rotation in 90° of arm abduction moving toward external rotation using the active movement extent discrimination apparatus), maximal throwing speed (MTS, meters per second measured via a radar gun), and accuracy (total error in centimeters determined by video analysis) at 80 and 100% of MTS. Although proprioception in the dominant and nondominant arms was significantly correlated with each other (r = 0.54, p < 0.01), no relationship was found between shoulder proprioception and performance. Shoulder proprioception was not a significant determinant of throwing performance such that high levels of speed and accuracy were achieved without a high degree of proprioception. There is no evidence to suggest therefore that this particular method of shoulder proprioception measurement should be implemented in clinical practice. Consequently, clinicians are encouraged to consider proprioception throughout the entire kinetic chain rather than the shoulder joint in isolation as a determining factor of performance in throwing athletes.

Throwing performance and test-retest reliability in Olympic female water polo players.

Shooting performance is critical to successful water polo performance, requiring high levels of speed and accuracy. However, shooting speed and accuracy performance of elite female water polo players has not been described in detail nor has the reliability of accuracy measures been reported. Consequently, the aim of this study was to describe shooting performance in elite female water polo players and compare the test-retest reliability of the currently available accuracy measures. Ten Olympic female water polo players were tested on 3 occasions before Olympic competition for maximal throwing speed and accuracy (total error and hit percentage) toward various target locations, with and without a goalkeeper (GK) present. The current participants (all Olympic athletes) achieved higher speeds (16.8 m·s-1), higher hit percentages (45.3%) of a 20-cm sniper net target, and lower errors (20.7 cm) than any other female water polo players investigated previously. Performance was similar across the different target locations; however, both speed (15.2 vs. 14.8 m·s-1; p ≤ 0.05) and accuracy (50.2 vs. 37.7%; p ≤ 0.05) were reduced in the presence of a GK. Speed and total error was similar across the 3 testing sessions; however, hit percentage was statistically significantly higher in the final session (58.8% vs. 40.4 and 36.4%). Maximal throwing speed showed high levels of test-retest reliability (0.96). Total error (intraclass correlation [ICC] = 0.79) had slightly greater reliability than hit percentage (ICC = 0.73) overall. Hit percentage (ICC = 0.82) showed slightly greater reliability than total error (ICC = 0.72) without a GK present, whereas total error (ICC = 0.79) showed much greater reliability than hit percentage (ICC = 0.34) when a GK was present. This study benchmarks the high degree of throwing speed and accuracy required at the Olympic level in female water polo players. Although resource intensive, total error is a reliable measure of accuracy that allows for the nature of error to be described in detail, providing a great level of insight into performance. Hit percentage, while easier to obtain, should only be used when a GK is not present and in situations where describing the nature of error does not add value to coaching practices.

Throwing speed and accuracy in baseball and cricket players.

Throwing speed and accuracy are both critical to sports performance but cannot be optimized simultaneously. This speed-accuracy trade-off (SATO) is evident across a number of throwing groups but remains poorly understood. The goal was to describe the SATO in baseball and cricket players and determine the speed that optimizes accuracy. 20 grade-level baseball and cricket players performed 10 throws at 80% and 100% of maximal throwing speed (MTS) toward a cricket stump. Baseball players then performed a further 10 throws at 70%, 80%, 90%, and 100% of MTS toward a circular target. Baseball players threw faster with greater accuracy than cricket players at both speeds. Both groups demonstrated a significant SATO as vertical error increased with increases in speed; the trade-off was worse for cricketers than baseball players. Accuracy was optimized at 70% of MTS for baseballers. Throwing athletes should decrease speed when accuracy is critical. Cricket players could adopt baseball-training practices to improve throwing performance.

Indicators of throwing arm fatigue in elite adolescent male baseball players: a randomized crossover trial.

Throwing carries an inherent risk of injury that worsens in the presence of arm fatigue. The purpose of this study was to identify markers that could facilitate the early detection of this type of fatigue, by comparing the response to bouts of throwing-specific and running-based exercise. Thirteen elite junior male baseball players were tested twice, 7 days apart with a randomized crossover design. They were assessed for shoulder proprioception, maximal throwing velocity, and throwing accuracy before and after a 10-minute bout of either throwing-specific (THROW) or general (RUN) exercise. Maximal throwing velocity was reduced similarly after both THROW and RUN bouts (-1.0 ± 0.4 vs. -0.6 ± 0.2 m·s-1, respectively; p ≤ 0.05); however, accuracy was only reduced after THROW (7.6 ± 3.4 cm; p ≤ 0.05). Arm soreness increased significantly more after THROW than RUN (3.5 ± 0.7 vs. 1.4 ± 0.5 km·h-1, respectively; p ≤ 0.05). Shoulder proprioception did not change after either exercise bout. The results suggest that throwing velocity is an indicator of general fatigue, whereas throwing accuracy and arm soreness are markers of arm fatigue. Shoulder proprioception does not seem to be a sensitive marker of either type of fatigue. Throwing velocity should be monitored to gauge overall fatigue levels, whereas accuracy and arm soreness should be closely monitored to gauge arm fatigue and throwing-induced injury risk.