Vascular changes of the hand in professional baseball players with emphasis on digital ischemia in catchers.

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Ginn, T Adam; Smith, Adam M; Snyder, Jon R; Koman, L Andrew; Smith, Beth P; Rushing, Julia

2005-07-01

Repetitive trauma to the hand is a concern for baseball players. The present study investigated the effects of repetitive trauma and the prevalence of microvascular pathological changes in the hands of minor league professional baseball players. In contrast to previous investigators, we documented the presence of abnormalities in younger, asymptomatic individuals. Thirty-six baseball players on active minor league rosters underwent a history and physical examination of both hands as well as additional specialized tests, including Doppler ultrasound, a timed Allen test, determination of digital brachial pressure indices, and ring sizing of fingers. Data were compared between gloved hands and throwing hands, hitters and nonhitters, and players at four different positions (catcher [nine subjects], outfielder [seven subjects], infielder [five subjects], and pitcher [fifteen subjects]). Digital brachial indices in the ring fingers of the gloved (p healthy professional baseball players in all positions, with a significantly higher prevalence in catchers, prior to the development of clinically important ischemia. Repetitive trauma resulting from the impact of the baseball also leads to digital hypertrophy in the index finger of the gloved hand of catchers. Gloves currently used by professional catchers do not adequately protect the hand from repetitive trauma.

Effects of neuromuscular joint facilitation on baseball pitching velocity and electromechanical reaction times of the teres major of young amateur baseball players.

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Wu, Peng; Huo, Ming; Maruyama, Hitoshi

2013-11-01

[Purpose] The aim of this study was to investigate the changes of baseball pitching velocity and electromechanical reaction times (EMG-RT) of the teres major of young amateur baseball players after neuromuscular joint facilitation (NJF) treatment. [Subjects] The subjects were 18 healthy males who were divided into two groups: a NJF group and a control group. The NJF group consisted of 10 subjects, and the control group consisted of 8 subjects. [Methods] Participants in the NJF group received NJF treatment. The baseball pitching velocity, the EMG-RT, the premotor time (PMT), and the motor time (MT) during shoulder internal rotation movement were measured before and after 8 weeks of exercise. [Results] There were no significant differences among the results of the control group. In the NJF group, there were significant differences in baseball pitching velocity, EMG-RT and MT after NJF treatment. [Conclusion] NJF intervention shortens not only EMG-RT but also MT, which implies that NJF is effective for motor processes. Since the baseball pitching velocity increased, NJF may be recommended for the improvement of the performance of baseball players.

A study of static, kinetic, and dynamic visual acuity in 102 Japanese professional baseball players

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Hoshina K

2013-03-01

Full Text Available Kohji Hoshina,1 Yuichi Tagami,2 Osamu Mimura,3 Hiroshi Edagawa,4 Masao Matsubara,5 Teiichi Nakayama6 1Hoshina Eye Clinic, Nishinomiya, Japan; 2Department of Ophthalmology, Kobe Century Memorial Hospital, Kobe, Japan; 3Department of Ophthalmology, Hyogo College of Medicine, Nishinomiya, Japan; 4Edagawa Eye Clinic, Tokyo, Japan; 5Department of Ophthalmology, Tokyo Women's Medical University Medical Center East, Tokyo, Japan; 6Ritsumeikan University, Kyoto, Japan Background: It seemed that visual functions might have some effects on the performance of baseball players. We measured static, kinetic, and dynamic visual acuity (SVA, KVA, and DVA, respectively of Japanese professional baseball players to ascertain whether there would be any difference in SVA, KVA, and DVA among player groups stratified according to their performance level. Methods: The subjects were 102 male professional baseball players with a mean age of 26 years who were members of a Japanese professional baseball club from 2000 to 2009. They were stratified into three groups according to their performance level: A (players who were on the roster of the top-level team all the time throughout the study period, B (players who were on the roster of the top-level team sometimes but not all the time, and C (players who were never on the roster of the top-level team. They were interviewed for the use of corrective visual aids, and examined for SVA, KVA, and DVA. The measurements of these parameters were compared among groups A, B, and C. We also investigated and analyzed the association of KVA or DVA with player position (pitchers or fielders and with hand dominance for batting. KVA was compared between the pitchers and the fielders because they each require different playing skills. DVA was compared between the right-handed and the left-handed batters. Results: There was no statistically significant difference among groups A, B, and C. There was a statistically significant difference in

Skin conditions of baseball, cricket, and softball players.

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Farhadian, Joshua A; Tlougan, Brook E; Adams, Brian B; Leventhal, Jonathan S; Sanchez, Miguel R

2013-07-01

Each year in the United States over 80 million people participate in bat-and-ball sports, for example baseball and softball. Cricket, the world's second most popular sport, is enjoyed by hundreds of millions of participants in such countries as India, Pakistan, Australia, New Zealand, Bangladesh, South Africa, West Indies, Sri Lanka, United Kingdom, and Zimbabwe. Although any player can develop skin disease as a result of participation in these bat-and-ball sports, competitive team athletes are especially prone to skin problems related to infection, trauma, allergy, solar exposure, and other causes. These diseases can produce symptoms that hinder individual athletic performance and participation. In this review, we discuss the diagnosis and best-practice management of skin diseases that can develop as a result of participation in baseball, softball, and cricket.

Effect of education and language on baseline concussion screening tests in professional baseball players.

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Jones, Nathaniel S; Walter, Kevin D; Caplinger, Roger; Wright, Daniel; Raasch, William G; Young, Craig

2014-07-01

The purpose of the present study was to investigate the possible effects of sociocultural influences, specifically pertaining to language and education, on baseline neuropsychological concussion testing as obtained via immediate postconcussion assessment and cognitive testing (ImPACT) of players from a professional baseball team. A retrospective chart review. Baseline testing of a professional baseball organization. Four hundred five professional baseball players. Age, languages spoken, hometown country location (United States/Canada vs overseas), and years of education. The 5 ImPACT composite scores (verbal memory, visual memory, visual motor speed, reaction time, impulse control) and ImPACT total symptom score from the initial baseline testing. The result of t tests revealed significant differences (P education, the significant differences (P < 0.05) remained in some scores. Sociocultural differences may result in differences in computer-based neuropsychological testing scores.

Concussions are associated with decreased batting performance among Major League Baseball players.

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Wasserman, Erin B; Abar, Beau; Shah, Manish N; Wasserman, Daniel; Bazarian, Jeffrey J

2015-05-01

Concussions impair balance, visual acuity, and reaction time--all of which are required for high-level batting performance--but the effects of concussion on batting performance have not been reported. The authors examined this relationship between concussion and batting performance among Major League Baseball (MLB) players. Batting performance among concussed MLB players will be worse upon return to play than batting performance among players missing time for noninjury reasons. Cohort study; Level of evidence, 3. The authors identified MLB players who sustained a concussion between 2007 and 2013 through league disabled-list records and a Baseball Prospectus database. For a comparison group, they identified players who went on paternity or bereavement leave during the same period. Using repeated-measures generalized linear models, the authors compared 7 batting metrics between the 2 groups for the 2 weeks upon return, as well as 4 to 6 weeks after return, controlling for pre-leave batting metrics, number of days missed, and position. The authors identified 66 concussions and 68 episodes of bereavement/paternity leave to include in the analysis. In the 2 weeks after return, batting average (.235 vs .266), on-base percentage (.294 vs .326), slugging percentage (.361 vs .423), and on-base plus slugging (.650 vs .749) were significantly lower among concussed players relative to the bereavement/paternity leave players (time×group interaction, Pperformance after concussion is adversely affected and to identify better measures to use for return-to-play decisions. © 2015 The Author(s).

Relationship Between the Relative Age Effect and Lengths of Professional Careers in Male Japanese Baseball Players: a Retrospective Analysis.

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Nakata, Hiroki

2017-12-01

The mechanisms underlying the relative age effect in sport events have been investigated for more than two decades. The present study focused on the relationship between the relative age effect and lengths of professional careers among professional male Japanese baseball players. The birth dates of players and lengths of professional careers were collected from an official publication, and data were divided into four quarters (Q1: April-June; Q2: July-September; Q3: October-December; Q4: January-March of the following year) grouped by 3 years. Based on the data for Q4, the expected numbers for the lengths of professional careers were calculated for Q1, Q2, and Q3. The number of players with professional careers of more than 19 years was significantly smaller in Q4 than in Q1, Q2, and Q3. The relative age effect among professional male Japanese baseball players was associated with the lengths of professional careers. Relative age appears to be a very important factor for the development of expertise among male Japanese baseball players and involves long-term disadvantages after becoming professional players.

Descriptive profile of hip rotation range of motion in elite tennis players and professional baseball pitchers.

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Ellenbecker, Todd S; Ellenbecker, Gail A; Roetert, E Paul; Silva, Rogerio Teixeira; Keuter, Greg; Sperling, Fabio

2007-08-01

Repetitive loading to the hip joint in athletes has been reported as a factor in the development of degenerative joint disease and intra-articular injury. Little information is available on the bilateral symmetry of hip rotational measures in unilaterally dominant upper extremity athletes. Side-to-side differences in hip joint range of motion may be present because of asymmetrical loading in the lower extremities of elite tennis players and professional baseball pitchers. Cohort (cross-sectional) study (prevalence); Level of evidence, 1. Descriptive measures of hip internal and external rotation active range of motion were taken in the prone position of 64 male and 83 female elite tennis players and 101 male professional baseball pitchers using digital photos and computerized angle calculation software. Bilateral differences in active range of motion between the dominant and nondominant hip were compared using paired t tests and Bonferroni correction for hip internal, external, and total rotation range of motion. A Pearson correlation test was used to test the relationship between years of competition and hip rotation active range of motion. No significant bilateral difference (P > .005) was measured for mean hip internal or external rotation for the elite tennis players or the professional baseball pitchers. An analysis of the number of subjects in each group with a bilateral difference in hip rotation greater than 10 degrees identified 17% of the professional baseball pitchers with internal rotation differences and 42% with external rotation differences. Differences in the elite male tennis players occurred in only 15% of the players for internal rotation and 9% in external rotation. Female subjects had differences in 8% and 12% of the players for internal and external rotation, respectively. Statistical differences were found between the mean total arc of hip range of internal and external rotation in the elite tennis players with the dominant side being greater

Internal- and External-Rotation Peak Toque in Little League Baseball Players With Subacromial Impingement Syndrome: Improved by Closed Kinetic Chain Shoulder Training.

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Lee, Dong-Rour; Kim, Laurentius Jongsoon

2016-08-01

Many studies have explored closed kinetic chain (CKC) shoulder exercises (SEs) with a sling because they are safer and more effective than open-chain exercises, especially in early stages of treatment. However, the application of CKC SE in youth baseball players has rarely been attempted, although teenage baseball players also experience shoulder pain. To investigate the effects of CKC SE on the peak torque of shoulder internal rotation (IR) and external rotation (ER) in youth baseball players. Single-group pretest, posttest. Biomechanics laboratory. 23 Little League Baseball players with subacromial impingement syndrome. The CKC SE with a sling was CKC shoulder-flexion exercise, extension exercise, IR exercise, and ER exercise. This exercise regimen was conducted 2 or 3 times/wk for 8 wk. The peak torque of shoulder IR and ER was measured using an isokinetic dynamometer. Concentric shoulder rotation was performed, with 5 repetitions at an angular velocity of 60°/s and 15 at 180°/s. The IR and ER peak torque significantly increased at each angular velocity after the exercise program. In particular, the increase in IR and ER peak torque values was statistically significant at an angular velocity of 180°/s. CKC SE was effective in increasing shoulder IR and ER strength, demonstrating its potential benefits in the prevention and treatment of shoulder injury. In addition, increased IR peak torque appears to improve throwing velocity in baseball players.

Mortality of major league baseball players from Canada, Latin America, and the Caribbean

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Robert J. Reynolds

2012-07-01

Full Text Available Professional baseball players have lower mortality rates than the US general population, but whether this is true of foreign-born players is not known. Using data on ballplayers from six nations, we compare mortality rates with those of US players via standardized mortality ratios. After controlling for confounders, four countries had statistically insignificant SMRs while two nations had significantly elevated SMRs. In the two nations with elevated SMRs, low average ages at death and high crime rates suggest the increased mortality may be linked to violent crime. A full understanding of the causes of disparity in mortality will require further research.

Mortality of major league baseball players from Canada, Latin America, and the Caribbean

Directory of Open Access Journals (Sweden)

Robert J. Reynolds

2012-01-01

Full Text Available Professional baseball players have lower mortality rates than the US general population, but whether this is true of foreign-born players is not known. Using data on ballplayers from six nations, we compare mortality rates with those of US players via standardized mortality ratios. After controlling for confounders, four countries had statistically insignificant SMRs while two nations had significantly elevated SMRs. In the two nations with elevated SMRs, low average ages at death and high crime rates suggest the increased mortality may be linked to violent crime. A full understanding of the causes of disparity in mortality will require further research.

The effect of ocular dominance on the performance of professional baseball players.

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Laby, D M; Kirschen, D G; Rosenbaum, A L; Mellman, M F

1998-05-01

The purpose of the study was to determine whether a performance difference exists between baseball players with "same" (right-right) and "crossed" (right-left) hand-ocular dominance. A cohort study design was used. Four hundred and ten major and minor league members of the Los Angeles Dodgers professional baseball team. Measurement of ocular dominance. Batting average and earned run average (ERA). Same/crossed dominance (with P values in parentheses) are as follows: Batting averages: major league-0.271/0.251 (0.20); minor league-0.274/0.270 (0.57); ERA: major league-3.34/3.56 (0.66); minor league-4.00/4.20 (0.54). Hand-ocular dominance patterns do not have an effect on batting average or ERA.

DIFFERENTIATION OF BODY COMPOSITION OF PLAYERS OF THE POLISH NATIONAL BASEBALL TEAM

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Marina Jagiełło

2014-10-01

Full Text Available The purpose of the study is to identify the differentiation of body composition among players of Polish national baseball team in comparison to persons of the same population not professionally engaged in sport. The study involved Polish baseball representatives (n=20. Competitors’ age was 18-28 years, body mass from 67.7 kg to 114 kg (85±10.3 kg, and body height 173-196 cm (185.1±4.8. The training experience was 7-14 years and it was highly differentiated. The stoutness factor is the dominant factor among "infielders" and "pitchers", and among "outfielders" - the length one. The proportions of the features within the factors show that players are characterized by a strongly muscled forearm and a shank and by a clear predominance of the elbow width with a disproportionately - to the overall size of the factor - small knee and shoulder width. In the length factor an even contribution of the upper and lower extremity length with lower sitting body height can be noted. Depending on the position on the field there is a differentiation of the internal proportions of the body.

Skill-Specific Changes in Somatosensory Nogo Potentials in Baseball Players.

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Koya Yamashiro

Full Text Available Athletic training is known to induce neuroplastic alterations in specific somatosensory circuits, which are reflected by changes in somatosensory evoked potentials and event-related potentials. The aim of this study was to clarify whether specific athletic training also affects somatosensory Nogo potentials related to the inhibition of movements. The Nogo potentials were recorded at nine cortical electrode positions (Fz, Cz, Pz, F3, F4, C3, C4, P3 and P4 in 12 baseball players (baseball group and in 12 athletes in sports, such as track and field events and swimming, that do not require response inhibition, such as batting for training or performance (sports group. The Nogo potentials and Go/Nogo reaction times (Go/Nogo RTs were measured under a somatosensory Go/Nogo paradigm in which subjects were instructed to rapidly push a button in response to stimulus presentation. The Nogo potentials were obtained by subtracting the Go trial from the Nogo trial. The peak Nogo-N2 was significantly shorter in the baseball group than that in the sports group. In addition, the amplitude of Nogo-N2 in the frontal area was significantly larger in the baseball group than that in the sports group. There was a significant positive correlation between the latency of Nogo-N2 and Go/Nogo RT. Moreover, there were significant correlations between the Go/Nogo RT and both the amplitude of Nogo-N2 and Nogo-P3 (i.e., amplitude of the Nogo-potentials increases with shorter RT. Specific athletic training regimens may induce neuroplastic alterations in sensorimotor inhibitory processes.

Effectiveness of Manual Therapy and Stretching for Baseball Players With Shoulder Range of Motion Deficits.

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Bailey, Lane B; Thigpen, Charles A; Hawkins, Richard J; Beattie, Paul F; Shanley, Ellen

Baseball players displaying deficits in shoulder range of motion (ROM) are at increased risk of arm injury. Currently, there is a lack of consensus regarding the best available treatment options to restore shoulder ROM. Instrumented manual therapy with self-stretching will result in clinically significant deficit reductions when compared with self-stretching alone. Controlled laboratory study. Shoulder ROM and humeral torsion were assessed in 60 active baseball players (mean age, 19 ± 2 years) with ROM deficits (nondominant - dominant, ≥15°). Athletes were randomly assigned to receive a single treatment of instrumented manual therapy plus self-stretching (n = 30) or self-stretching only (n = 30). Deficits in internal rotation, horizontal adduction, and total arc of motion were compared between groups immediately before and after a single treatment session. Treatment effectiveness was determined by mean comparison data, and a number-needed-to-treat (NNT) analysis was used for assessing the presence of ROM risk factors. Prior to intervention, players displayed significant ( P < 0.001) dominant-sided deficits in internal rotation (-26°), total arc of motion (-18°), and horizontal adduction (-17°). After the intervention, both groups displayed significant improvements in ROM, with the instrumented manual therapy plus self-stretching group displaying greater increases in internal rotation (+5°, P = 0.010), total arc of motion (+6°, P = 0.010), and horizontal adduction (+7°, P = 0.004) compared with self-stretching alone. For horizontal adduction deficits, the added use of instrumented manual therapy with self-stretching decreased the NNT to 2.2 (95% CI, 2.1-2.4; P = 0.010). Instrumented manual therapy with self-stretching significantly reduces ROM risk factors in baseball players with motion deficits when compared with stretching alone. The added benefits of manual therapy may help to reduce ROM deficits in clinical scenarios where stretching alone is

Throwing-related injuries of the subscapularis in professional baseball players

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Polster, Joshua M.; Ilaslan, Hakan; Subhas, Naveen [Cleveland Clinic, Imaging Institute, Cleveland, OH (United States); Lynch, T.S. [Columbia University Medical Center, Center for Shoulder, Elbow and Sports Medicine, New York, NY (United States); Bullen, Jennifer A. [Cleveland Clinic, Quantitative Health Sciences, Cleveland, OH (United States); Soloff, Lonnie [Cleveland Indians, Cleveland, OH (United States); Schickendantz, Mark S. [Cleveland Clinic, Orthopedic and Rheumatologic Institute, Cleveland, OH (United States)

2016-01-15

To describe the MR appearance of a series of throwing-related injuries to the subscapularis muscle-tendon complex among baseball players. A retrospective review of MR scans of the shoulder in players from 1 professional baseball organization over the course of 5 years was performed to identify cases with findings suggestive of subscapularis injury. These findings were graded and the medical record was reviewed to assess clinical findings, treatment, and follow-up. Preinjury baseline measurements of arm external rotation at 90 of abduction were compared to measurements from a noninjured cohort to evaluate whether this measure is a risk factor for injury. A total of 133 MR scans of the shoulder were evaluated. Eleven of the scans demonstrated signal changes suggesting subscapularis injury; 10 of these 11 patients had clinical findings supporting a diagnosis of throwing-related subscapularis strain. There were four grade 1, four grade 2, and two grade 3 injuries. All injuries occurred in the inferior half of the subscapularis at the myotendinous junction. Risk of subscapularis injury increased with lower levels of dominant arm external rotation (odds ratio, 1.12; 95 % CI, 1.07-1.21; p < 0.001). A threshold of dominant arm external rotation of <106 demonstrated sensitivity of 0.700 (95 % CI, 0.392-0.897) and specificity of 0.951 (95 % CI, 0.888-0.982) for subscapularis injury. Throwing-related subscapularis injuries occur in the inferior half of the muscle at the myotendinous junction. Our data suggest that there is an increased risk of these injuries with lower levels of dominant arm external rotation. (orig.)

Throwing-related injuries of the subscapularis in professional baseball players

International Nuclear Information System (INIS)

Polster, Joshua M.; Ilaslan, Hakan; Subhas, Naveen; Lynch, T.S.; Bullen, Jennifer A.; Soloff, Lonnie; Schickendantz, Mark S.

2016-01-01

To describe the MR appearance of a series of throwing-related injuries to the subscapularis muscle-tendon complex among baseball players. A retrospective review of MR scans of the shoulder in players from 1 professional baseball organization over the course of 5 years was performed to identify cases with findings suggestive of subscapularis injury. These findings were graded and the medical record was reviewed to assess clinical findings, treatment, and follow-up. Preinjury baseline measurements of arm external rotation at 90 of abduction were compared to measurements from a noninjured cohort to evaluate whether this measure is a risk factor for injury. A total of 133 MR scans of the shoulder were evaluated. Eleven of the scans demonstrated signal changes suggesting subscapularis injury; 10 of these 11 patients had clinical findings supporting a diagnosis of throwing-related subscapularis strain. There were four grade 1, four grade 2, and two grade 3 injuries. All injuries occurred in the inferior half of the subscapularis at the myotendinous junction. Risk of subscapularis injury increased with lower levels of dominant arm external rotation (odds ratio, 1.12; 95 % CI, 1.07-1.21; p < 0.001). A threshold of dominant arm external rotation of <106 demonstrated sensitivity of 0.700 (95 % CI, 0.392-0.897) and specificity of 0.951 (95 % CI, 0.888-0.982) for subscapularis injury. Throwing-related subscapularis injuries occur in the inferior half of the muscle at the myotendinous junction. Our data suggest that there is an increased risk of these injuries with lower levels of dominant arm external rotation. (orig.)

Outcomes and Return to Sport After Ulnar Collateral Ligament Reconstruction in Adolescent Baseball Players.

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Saper, Michael; Shung, Joseph; Pearce, Stephanie; Bompadre, Viviana; Andrews, James R

2018-04-01

The number of ulnar collateral ligament (UCL) reconstructions in adolescent athletes has increased over the past 2 decades. Clinical results in this population have not been well studied. The purpose of this study was to evaluate the outcomes and return to sport after UCL reconstruction in a large group of adolescent baseball players. We hypothesized that excellent clinical outcomes and high rates of return to sport would be observed in this population at a minimum 2-year follow-up. Case series; Level of evidence, 4. We reviewed 140 adolescent (aged ≤19 years) baseball players who underwent UCL reconstruction with the American Sports Medicine Institute (ASMI) technique by a single surgeon. Medical records were reviewed for patient demographics, injury characteristics, operative details, and surgical complications. Patient-reported outcomes were assessed using the Conway scale, the Andrews-Timmerman (A-T) score, the Kerlan-Jobe Orthopaedic Clinic (KJOC) score, and a 0- to 100-point subjective scale for elbow function and satisfaction. Return to sporting activity was assessed using a custom-designed questionnaire. The mean age at the time of surgery was 18.0 years (range, 13-19 years), and the mean follow-up was 57.9 months (range, 32.4-115.4 months). Over half (60%) of patients were high school athletes. The mean duration of symptoms before surgery was 6.9 months (range, 0.5-60.0 months). Partial tears were identified in 57.9% of patients, and 41.3% of patients had preoperative ulnar nerve symptoms. Graft type included the ipsilateral palmaris in 77.1% of patients. Concomitant procedures were performed in 25% of patients. Outcomes on the Conway scale were "excellent" in 86.4% of patients. The mean A-T and KJOC scores were 97.3 ± 6.1 and 85.2 ± 14.6, respectively. Mean patient satisfaction was 94.4. Overall, 97.8% of patients reported returning to sport at a mean of 11.6 months (range, 5-24 months), and 89.9% of patients returned to sport at the same level of

Visual abilities distinguish pitchers from hitters in professional baseball.

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Klemish, David; Ramger, Benjamin; Vittetoe, Kelly; Reiter, Jerome P; Tokdar, Surya T; Appelbaum, Lawrence Gregory

2018-01-01

This study aimed to evaluate the possibility that differences in sensorimotor abilities exist between hitters and pitchers in a large cohort of baseball players of varying levels of experience. Secondary data analysis was performed on 9 sensorimotor tasks comprising the Nike Sensory Station assessment battery. Bayesian hierarchical regression modelling was applied to test for differences between pitchers and hitters in data from 566 baseball players (112 high school, 85 college, 369 professional) collected at 20 testing centres. Explanatory variables including height, handedness, eye dominance, concussion history, and player position were modelled along with age curves using basis regression splines. Regression analyses revealed better performance for hitters relative to pitchers at the professional level in the visual clarity and depth perception tasks, but these differences did not exist at the high school or college levels. No significant differences were observed in the other 7 measures of sensorimotor capabilities included in the test battery, and no systematic biases were found between the testing centres. These findings, indicating that professional-level hitters have better visual acuity and depth perception than professional-level pitchers, affirm the notion that highly experienced athletes have differing perceptual skills. Findings are discussed in relation to deliberate practice theory.

Changes in Cuba’s Migration Policy and Its Impact on Baseball

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Onesimo Julian Moreira Seijos

2014-11-01

Full Text Available Baseball is an essential constituent of the Cuban national identity. For nearly a century, Cuban baseball players had joined high-ranking international leagues, including the Negro Leagues and Major League Baseball (MLB of the United States. After the triumph of the Revolution in 1959, the professional practice of sport was banned in the country. On the other hand, the revolutionary government instituted migration rules that disallowed Cuban citizens to travel abroad freely. Until the collapse of the Soviet Union, the Cuban national baseball team reigned in amateur competitions worldwide. Sporting successes in general and those of baseball in particular, were managed by the government as a political tool; the government used to display the loyalty of the athletes as a triumph of the Cuban system. However, since the nineties there has been a growing departure of Cuban top baseball players who have had the target of entering in MLB franchises, disregarding that the Cuban migration policy had remained unwavering. On the other hand, after the enactment of changes in the Cuban migration policy in 2013, the unconventional departure of high performance baseball players has increased sharply. The relationship between the migration reform and the increased leakage of baseball players has not been studied by scholars. The relevance of this paper is that it is the first academic approach to that relationship. This paper discusses the migration reform in Cuba and focuses mainly on its impact on baseball.

Predicting Intentions to Eat a Healthful Diet by College Baseball Players: Applying the Theory of Planned Behavior

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Pawlak, Roman; Malinauskas, Brenda; Rivera, David

2009-01-01

Objective: To assess factors important to college baseball players regarding intention to eat a healthful diet within the Theory of Planned Behavior. Design: A survey based on the Theory of Planned Behavior was administered during the 2006 summer league season from 5 of the Northern Division teams of the Coastal Plain League. Participants: Male…

Expert Baseball Batters Have Greater Sensitivity in Making Swing Decisions

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Gray, Rob

2010-01-01

This study used signal detection theory to conceptualize the problem a baseball batter faces when deciding whether or not to swing at a pitch. It examined the launch angle (LA) criteria used by expert (college players) and less experienced (recreational league players) batters using a baseball batting simulation. This study showed that, although…

Three lessons for genetic toxicology from baseball analytics.

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Dertinger, Stephen D

2017-07-01

In many respects the evolution of baseball statistics mirrors advances made in the field of genetic toxicology. From its inception, baseball and statistics have been inextricably linked. Generations of players and fans have used a number of relatively simple measurements to describe team and individual player's current performance, as well as for historical record-keeping purposes. Over the years, baseball analytics has progressed in several important ways. Early advances were based on deriving more meaningful metrics from simpler forerunners. Now, technological innovations are delivering much deeper insights. Videography, radar, and other advances that include automatic player recognition capabilities provide the means to measure more complex and useful factors. Fielders' reaction times, efficiency of the route taken to reach a batted ball, and pitch-framing effectiveness come to mind. With the current availability of complex measurements from multiple data streams, multifactorial analyses occurring via machine learning algorithms have become necessary to make sense of the terabytes of data that are now being captured in every Major League Baseball game. Collectively, these advances have transformed baseball statistics from being largely descriptive in nature to serving data-driven, predictive roles. Whereas genetic toxicology has charted a somewhat parallel course, a case can be made that greater utilization of baseball's mindset and strategies would serve our scientific field well. This paper describes three useful lessons for genetic toxicology, courtesy of the field of baseball analytics: seek objective knowledge; incorporate multiple data streams; and embrace machine learning. Environ. Mol. Mutagen. 58:390-397, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Smokeless tobacco use and health effects among baseball players.

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Ernster, V L; Grady, D G; Greene, J C; Walsh, M; Robertson, P; Daniels, T E; Benowitz, N; Siegel, D; Gerbert, B; Hauck, W W

1990-07-11

The effects of smokeless tobacco (ST) use were studied in 1109 members of major and minor league professional baseball teams during spring training in 1988. The prevalence of current ST use was 39%. The median age at initiation among users was 18 years, and the median duration of use was 5 years. Among users, 75% cited a snuff brand as their usual ST product. Oral leukoplakia was present in 46% (196/423) of current-week ST users and 1.4% (7/493) of nonusers (odds ratio, 60; 95% confidence interval, 28 to 130). Prevalence of oral leukoplakia among ST users increased with hours used per day and decreased with time lapsed since last use, and was higher in snuff users than in chewing tobacco users. Of the subjects with oral leukoplakia who underwent punch biopsy, 91 had benign hyperkeratosis and one had mild dysplasia. Overall prevalence of dental caries, gingivitis, and plaque did not differ between ST users and nonusers. In analyses confined to facial surfaces of mandibular incisor teeth, where ST is most commonly used, there were significant increases among users in both gingival recession and attachment loss. Users of ST did not differ from nonusers in blood pressure, pulse, total or high-density lipoprotein cholesterol level, or white blood cell count, but among users high-density lipoprotein cholesterol levels were inversely associated with serum cotinine levels. The major health effects of ST use among professional baseball players are oral leukoplakia and localized periodontal disease. The study population was young, physically fit, and characterized by relatively moderate short-term ST use.

Going, Going, Gone! The Making of a Baseball Bat

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Cantu, Diana

2012-01-01

From little league players to professional athletes, baseball has become a sport that is not only fun to play and watch, but also a sport driven by innovation and technology. One particular piece of baseball equipment that has undergone many changes is the baseball bat. Prior to the early 1970s, wooden bats were the only choice available. Today,…

Test del PWC 170 adaptado para determinar la capacidad de trabajo especial en beisbolistas escolares / Adapted PWC 170 test to determine special work abilities in school baseball players

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Sadiel López-Leal

2016-07-01

Full Text Available Resumen Se adaptó el test de PWC 170, según el método de Karpman modificado para el bateo, con el propósito de determinar la capacidad de trabajo especial durante este ejercicio en beisbolistas de la categoría 9-10 años del área deportiva Julio Antonio Mella, ciudad de Camagüey, Cuba. Se estudiaron 15 atletas. Como métodos se emplearon la revisión bibliográfica sobre el proceso de control de preparación del deportista y el control médico deportivo, además se realizó la entrevista a entrenadores y la observación de clases. De su aplicación se obtuvo como resultado una alta correlación entre ambas experiencias y buena estabilidad, además de positivas valoraciones de todos los indicadores por parte de los entrenadores; de ahí que consideren efectiva esta prueba para evaluar objetivamente la capacidad de trabajo especial en beisbolistas escolares de Camagüey. Abstract The PWC 170 test was adapted, according to Karpman’s model modified for batting, with the purpose of determining special work abilities during the game in 9-10 years old baseball players of Julio Antonio Mella sports area, Camagüey city, Cuba. The sample was of 15 athletes. Some of the scientific methods used were bibliographic revision on the control process of the athletes training, coach interviews and class observation. As a result the author detected a high correlation of experiences, good stability and positive coach assessment on every indicator. Therefore, this test was considered effective to objectively evaluate special work abilities in school baseball players from Camagüey.

Hamstring Injuries in Major and Minor League Baseball

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Zachazewski, James; Silvers, Holly J.; Li, Bernard; Snyder-Mackler, Lynn; Insler, Stephanie; Ahmad, Christopher S.; Mandelbaum, Bert R.

2016-01-01

Objectives: The purpose of this study is to test the efficacy of a hamstring injury prevention program designed to address the high incidence of acute and chronic hamstring injuries and re-injuries that occur in the sport of professional baseball. Methods: This was a prospective cluster cohort study assessing the efficacy of an injury prevention intervention designed to address hamstring injury in rookie and professional baseball players participating in Minor and Major League Baseball (N = 2...

Sensorimotor abilities predict on-field performance in professional baseball.

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Burris, Kyle; Vittetoe, Kelly; Ramger, Benjamin; Suresh, Sunith; Tokdar, Surya T; Reiter, Jerome P; Appelbaum, L Gregory

2018-01-08

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.

Evaluation of hip internal and external rotation range of motion as an injury risk factor for hip, abdominal and groin injuries in professional baseball players

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Xinning Li

2015-12-01

Full Text Available Normal hip range of motion (ROM is essential in running and transfer of energy from lower to upper extremities during overhead throwing. Dysfunctional hip ROM may alter lower extremity kinematics and predispose athletes to hip and groin injuries. The purpose of this study is characterize hip internal/external ROM (Arc and its effect on the risk of hip, hamstring, and groin injuries in professional baseball players. Bilateral hip internal and external ROM was measured on all baseball players (N=201 in one professional organization (major and minor league during spring training. Players were organized according to their respective positions. All injuries were documented prospectively for an entire MLB season (2010 to 2011. Data was analyzed according to position and injuries during the season. Total number of players (N=201 with an average age of 24±3.6 (range=17-37. Both pitchers (N=93 and catchers (N=22 had significantly decreased mean hip internal rotation and overall hip arc of motion compared to the positional players (N=86. Players with hip, groin, and hamstring injury also had decreased hip rotation arc when compared to the normal group. Overall, there is a correlation between decreased hip internal rotation and total arc of motion with hip, hamstring, and groin injuries.

Does well maintained graft provide consistent return to play after medial ulnar collateral ligament reconstruction of the elbow joint in elite baseball players?

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Park, Jin-Young; Oh, Kyung-Soo; Bahng, Seung-Chul; Chung, Seok-Won; Choi, Jin-Ho

2014-06-01

Several studies have reported the clinical outcomes of medial ulnar collateral ligament (MUCL) reconstruction of the elbow joint in throwing athletes, including the rate of return to sports. However, little has been known about the imaging outcomes after MUCL reconstruction. The aim of this study is to report the clinical and imaging outcomes after MUCL reconstruction using figure of eight fashion in the elite and professional baseball players. This study included 17 baseball players, who underwent MUCL reconstruction between July 2007 and May 2010. The average follow-up period was 48.6 months. Imaging assessment consisted of preoperative plain and stress radiographs, magnetic resonance imaging, and postoperative serial ultrasonography. The clinical assessments were composed of visual analogue scale (VAS) for pain, range of motion, and the Conway scale. The mean VAS score was 6.4 (range, 3 to 8) preoperatively and 2.2 (range, 0 to 4) postoperatively (p returned to sports at the same or higher level compared to preinjury. Serial ultrasonography revealed well-maintained grafts at 3 and 12 months in all of the players. Five out of 17 players showed decreased echogenecity in the common flexor tendon at 3 months, which was considered as remaining tissue swelling and resolved completely at 12 months. All grafts are well-maintained until 12-months based on the ultrasonographic findings, although only 53% of the players returned to preinjury level.

Are Canadian-born Major League Baseball players more likely to bat left-handed? A partial test of the hockey-influence on batting hypothesis.

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Cairney, John; Chirico, Daniele; Li, Yao-Chuen; Bremer, Emily; Graham, Jeffrey D

2018-01-01

It has been suggested that Canadian-born Major League Baseball (MLB) players are more likely to bat left-handed, possibly owing to the fact that they learn to play ice hockey before baseball, and that there is no clear hand-preference when shooting with a hockey stick; approximately half of all ice hockey players shoot left. We constructed a database on active (i.e., October, 2016) MLB players from four countries/regions based on place of birth (Canada, United States of America [USA], Dominican Republic and South Asia [i.e., Japan, Taiwan and South Korea]), including information on which hand they use to bat and throw. We also extracted information on all Canadian-born MLB players, dating back to 1917. Our results confirm that the proportion of left-handed batters born in Canada is higher when compared to the other countries selected; also, since 1917, the proportion of Canadian MLB players who bat left has been consistently higher than the league average. We also compared the proportion of left-handed batters in Canada with players born in states in the USA grouped into high, average and low based on hockey participation. The proportion of MLB players born in states with a high level of hockey participation were more likely to bat left, although the differences were significant at trend level only (p bat left-handed, this did not correspond with a greater left-hand dominance, as determined by throwing hand. In conclusion, the present study confirms that Canadian-born MLB players are more likely to bat left-handed when compared to American, Dominican Republic and South Asian-born MLB players, providing partial support for the hockey influence on batting hypothesis.

Mouthguard BITES (behavior, impulsivity, theory evaluation study): what drives mouthguard use among high school basketball and baseball/softball athletes.

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Collins, Christy L; McKenzie, Lara B; Roberts, Kristin J; Fields, Sarah K; Comstock, R Dawn

2015-10-01

Although mouthguards are effective, inexpensive, easy to use, and readily available, this form of protective equipment has been underutilized. "Impulsive delay discounting" (an index of impulsive behavior) among high school athletes may help explain their decision making regarding use of protective equipment such as mouthguards. We investigated the relationship between high school baseball, softball, and basketball players' mouthguard use, impulsive delay discounting, and the precaution adoption process model (a behavior change theory). A convenience sample of boys' and girls' basketball and baseball/softball players at 21 high schools in the Greater Columbus, Ohio, metro area completed a self-administered survey that captured their demographic information, knowledge, attitudes, and beliefs regarding mouthguard use, impulsive delay discounting, and precaution adoption process model stage. We surveyed a total of 1636 students (55.9 % male, 43.8 % female, 0.3 % unknown). Only 12.3 % reported using a mouthguard either every time or sometimes during practice or competition. The primary reasons reported for not wearing mouthguards were they were not required to (65.3 %) and that the athletes could not breathe or talk while wearing one (61.5 %). These reasons were consistent across sex and sport. Most athletes reported that their coaches (87.3 %) and parents (64.5 %) had never talked to them about wearing a mouthguard. Lower precaution adoption process model stage was significantly associated with higher impulsivity (p softball remains low despite the risk of dental injury in these sports. Effective, evidence-based, targeted, and tailored interventions to improve adolescent athletes' use of mouthguards to prevent sports-related dental injuries should be based on the specific behavioral and social factors influencing each athlete's decision making regarding use of mouthguards.

Modulation of motor area activity by the outcome for a player during observation of a baseball game.

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Sotaro Shimada

Full Text Available BACKGROUND: Observing competitive games such as sports is a pervasive entertainment among humans. The inclination to watch others play may be based on our social-cognitive ability to understand the internal states of others. The mirror neuron system, which is activated when a subject observes the actions of others, as well as when they perform the same action themselves, seems to play a crucial role in this process. Our previous study showed that activity of the mirror neuron system was modulated by the outcome of the subject's favored player during observation of a simple competitive game (rock-paper-scissors. However, whether the mirror neuron system responds similarly in a more complex and naturalistic sports game has not yet been fully investigated. METHODOLOGY/PRINCIPAL FINDINGS: In the present study, we measured the activity of motor areas when the subjects, who were amateur baseball field players (non-pitchers, watched short movie clips of scenes in professional baseball games. The subjects were instructed to support either a batter or a pitcher when observing the movie clip. The results showed that activity in the motor area exhibited a strong interaction between the subject's supported side (batter or pitcher and the outcome (a hit or an out. When the subject supported the batter, motor area activity was significantly higher when the batter made an out than when he made a hit. However, such modulation was not apparent when the subject supported the pitcher. CONCLUSIONS/SIGNIFICANCE: This result indicates that mirror neuron system activity is modulated by the outcome for a particular player in a competitive game even when observing a complex and naturalistic sports game. We suggest that our inclination to watch competitive games is facilitated by this characteristic of the mirror neuron system.

Investigating customer racial discrimination in the secondary baseball card market.

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Primm, Eric; Piquero, Nicole Leeper; Piquero, Alex R; Regoli, Robert M

2011-01-01

A growing body of literature in a variety of disciplines has appeared over the last 20 years examining customer racial bias in the secondary sports card market; however, consensus on the matter has yet to emerge. In this article, we explore the more subtle ways that a player's race/ethnicity may affect the value of his sports card including a player's skin tone (light- to dark-skinned). Data were obtained for 383 black, Latino, and white baseball players who had received at least one vote for induction into Major League Baseball's Hall of Fame including their career performance statistics, rookie card price, card availability, Hall of Fame status, and skin tone. Findings indicate that card availability is the primary determinant of card value while a player's skin tone has no direct effect. Subsequent analysis demonstrates that a player's race (white/non-white) rather than skin tone did have an effect as it interacts with Hall of Fame status to influence his rookie card price.

Similar photoperiod-related birth seasonalities among professional baseball players and lesbian women with an opposite seasonality among gay men: Maternal melatonin may affect fetal sexual dimorphism.

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Marzullo, Giovanni

2014-05-30

Based on pre-mid-20th-century data, the same photoperiod-related birth seasonality previously observed in schizophrenia was also recently found in neural-tube defects and in extreme left-handedness among professional baseball players. This led to a hypothesis implicating maternal melatonin and other mediators of sunlight actions capable of affecting 4th-embryonic-week developments including neural-tube closure and left-right differentiation of the brain. Here, new studies of baseball players suggest that the same sunlight actions could also affect testosterone-dependent male-female differentiation in the 4-month-old fetus. Independently of hand-preferences, baseball players (n=6829), and particularly the stronger hitters among them, showed a unique birth seasonality with an excess around early-November and an equally significant deficit 6 months later around early-May. In two smaller studies, north-American and other northern-hemisphere born lesbians showed the same strong-hitter birth seasonality while gay men showed the opposite seasonality. The sexual dimorphism-critical 4th-fetal-month testosterone surge coincides with the summer-solstice in early-November births and the winter-solstice in early-May births. These coincidences are discussed and a "melatonin mechanism" is proposed based on evidence that in seasonal breeders maternal melatonin imparts "photoperiodic history" to the newborn by direct inhibition of fetal testicular testosterone synthesis. The present effects could represent a vestige of this same phenomenon in man. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Preventive Effects of Eccentric Training on Acute Hamstring Muscle Injury in Professional Baseball

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Seagrave, Richard A.; Perez, Luis; McQueeney, Sean; Toby, E. Bruce; Key, Vincent; Nelson, Joshua D.

2014-01-01

Background: Hamstring injuries are the second most common injury causing missed days in professional baseball field players. Recent studies have shown the preventive benefit of eccentric conditioning on the hamstring muscle group in injury prevention. Specifically, Nordic-type exercises have been shown to decrease the incidence of acute hamstring injuries in professional athletes. Purpose: This was a prospective study performed in coordination with a single Major League Baseball (MLB) organization (major and minor league teams) that targeted the effects of Nordic exercises on the incidence of acute hamstring injuries in the professional-level baseball player. Study Design: Prospective cohort study; Level of evidence, 2. Methods: The daily workouts of 283 professional baseball players throughout all levels of a single MLB organization were prospectively recorded. The intervention group participated in the Nordic exercise program and was compared with a randomly selected control group of professional athletes within the organization not participating in the exercise program. The incidence of hamstring injuries in both groups was compared, and the total number of days missed due to injury was compared with the 2 previous seasons. Results: There were 10 hamstring injuries that occurred during the 2012 season among the 283 professional athletes that required removal from play. There were no injuries that occurred in the intervention group (n = 65, 0.00%; P = .0381). The number needed to treat (NNT) to prevent 1 hamstring injury was 11.3. The average repetitions per week of the injured group were assessed at multiple time points (2, 4, 6, and total weeks) prior to injury. There were significantly fewer repetitions per week performed in the injured group at all time points compared with overall average repetitions per week in the noninjured group (P = .0459, .0127, .0164, and .0299, respectively). After beginning the Nordic exercise program, there were 136 total days

Spectrum of shoulder injuries in the baseball pitcher

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Ouellette, Hugue; Bredella, Miriam; Palmer, William E.; Sheah, Kenneth; Torriani, Martin [Massachusetts General Hospital, Boston, Massachusetts (United States); Labis, John [Methodist Hospital, Houston, Texas (United States)

2008-06-15

This review describes a range of shoulder injuries experienced by baseball pitchers. It is estimated that more than 57% of pitchers suffer some form of shoulder injury during a playing season. Knowledge of the overhead throwing cycle is crucial for our understanding of these shoulder injuries. Baseball pitchers are prone to rotator cuff tears from tensile overload and impingement. Glenoid labrum degeneration or tears are also common, due to overuse syndrome (micro-instability), internal impingement and microtrauma. An understanding of the lesions involved in overhead throwing is crucial in baseball pitchers, as long-term disability can result from these injuries, sometimes with severe financial consequences to the player. (orig.)

Spectrum of shoulder injuries in the baseball pitcher

International Nuclear Information System (INIS)

Ouellette, Hugue; Bredella, Miriam; Palmer, William E.; Sheah, Kenneth; Torriani, Martin; Labis, John

2008-01-01

This review describes a range of shoulder injuries experienced by baseball pitchers. It is estimated that more than 57% of pitchers suffer some form of shoulder injury during a playing season. Knowledge of the overhead throwing cycle is crucial for our understanding of these shoulder injuries. Baseball pitchers are prone to rotator cuff tears from tensile overload and impingement. Glenoid labrum degeneration or tears are also common, due to overuse syndrome (micro-instability), internal impingement and microtrauma. An understanding of the lesions involved in overhead throwing is crucial in baseball pitchers, as long-term disability can result from these injuries, sometimes with severe financial consequences to the player. (orig.)

The Effects of a Sports Nutrition Education Intervention on Nutritional Status, Sport Nutrition Knowledge, Body Composition, and Performance during Off Season Training in NCAA Division I Baseball Players

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Fabrício Eduardo Rossi, Andrew Landreth, Stacey Beam, Taylor Jones, Layne Norton, Jason Michael Cholewa

2017-03-01

Full Text Available This study investigated the effects of a sport nutrition education intervention (SNEI on dietary intake, knowledge, body composition, and performance in NCAA Division I baseball players. Resistance trained NCAA Division I baseball players (82.4 ± 8.2 kg; 1.83 ± 0.06 m; 13.7 ± 5 % body fat participated in the study during 12 weeks of off-season training. Fifteen players volunteered for SNEI while 15 players matched for position served as controls (C for body composition and performance. The nutrition intervention group (NI received a 90 min SNEI encompassing energy intake (Kcal, carbohydrate (CHO, protein (PRO, fat, food sources, and hydration. Sport nutrition knowledge questionnaires were administered to NI pre and post. Nutritional status was determined by three-day dietary logs administered to NI pre and post. Body composition and performance (5-10-5 shuttle test, vertical jump, broad jump, 1 RM squat were measured pre and post for C and NI. Knowledge increased in NI. Pro and fat, but not CHO intake increased in NI. FM decreased pre to post in NI (11.5 ± 4.8 vs. 10.5 ± 5.4 kg but not C (11.3 ± 4.7 vs. 11.9 ± 4.5 kg. FFM increased pre to post with no differences between groups. The 5-10-5 shuttle times decreased significantly more in NI (4.58 ± 0.15 vs. 4.43 ± 0.13 sec compared to C (4.56 ± 0.18 vs. 4.50 ± 0.16 sec. Jump and squat performance increased pre to post with no differences between groups. Our findings indicate that an off season SNEI is effective at improving sport nutrition knowledge and some, but not all, nutrient intakes and performance measures in Division I baseball players.

The Effects of a Sports Nutrition Education Intervention on Nutritional Status, Sport Nutrition Knowledge, Body Composition, and Performance during Off Season Training in NCAA Division I Baseball Players.

Science.gov (United States)

Rossi, Fabrício Eduardo; Landreth, Andrew; Beam, Stacey; Jones, Taylor; Norton, Layne; Cholewa, Jason Michael

2017-03-01

This study investigated the effects of a sport nutrition education intervention (SNEI) on dietary intake, knowledge, body composition, and performance in NCAA Division I baseball players. Resistance trained NCAA Division I baseball players (82.4 ± 8.2 kg; 1.83 ± 0.06 m; 13.7 ± 5 % body fat) participated in the study during 12 weeks of off-season training. Fifteen players volunteered for SNEI while 15 players matched for position served as controls (C) for body composition and performance. The nutrition intervention group (NI) received a 90 min SNEI encompassing energy intake (Kcal), carbohydrate (CHO), protein (PRO), fat, food sources, and hydration. Sport nutrition knowledge questionnaires were administered to NI pre and post. Nutritional status was determined by three-day dietary logs administered to NI pre and post. Body composition and performance (5-10-5 shuttle test, vertical jump, broad jump, 1 RM squat) were measured pre and post for C and NI. Knowledge increased in NI. Pro and fat, but not CHO intake increased in NI. FM decreased pre to post in NI (11.5 ± 4.8 vs. 10.5 ± 5.4 kg) but not C (11.3 ± 4.7 vs. 11.9 ± 4.5 kg). FFM increased pre to post with no differences between groups. The 5-10-5 shuttle times decreased significantly more in NI (4.58 ± 0.15 vs. 4.43 ± 0.13 sec) compared to C (4.56 ± 0.18 vs. 4.50 ± 0.16 sec). Jump and squat performance increased pre to post with no differences between groups. Our findings indicate that an off season SNEI is effective at improving sport nutrition knowledge and some, but not all, nutrient intakes and performance measures in Division I baseball players.

Brain dynamics of post-task resting state are influenced by expertise: Insights from baseball players.

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Muraskin, Jordan; Dodhia, Sonam; Lieberman, Gregory; Garcia, Javier O; Verstynen, Timothy; Vettel, Jean M; Sherwin, Jason; Sajda, Paul

2016-12-01

Post-task resting state dynamics can be viewed as a task-driven state where behavioral performance is improved through endogenous, non-explicit learning. Tasks that have intrinsic value for individuals are hypothesized to produce post-task resting state dynamics that promote learning. We measured simultaneous fMRI/EEG and DTI in Division-1 collegiate baseball players and compared to a group of controls, examining differences in both functional and structural connectivity. Participants performed a surrogate baseball pitch Go/No-Go task before a resting state scan, and we compared post-task resting state connectivity using a seed-based analysis from the supplementary motor area (SMA), an area whose activity discriminated players and controls in our previous results using this task. Although both groups were equally trained on the task, the experts showed differential activity in their post-task resting state consistent with motor learning. Specifically, we found (1) differences in bilateral SMA-L Insula functional connectivity between experts and controls that may reflect group differences in motor learning, (2) differences in BOLD-alpha oscillation correlations between groups suggests variability in modulatory attention in the post-task state, and (3) group differences between BOLD-beta oscillations that may indicate cognitive processing of motor inhibition. Structural connectivity analysis identified group differences in portions of the functionally derived network, suggesting that functional differences may also partially arise from variability in the underlying white matter pathways. Generally, we find that brain dynamics in the post-task resting state differ as a function of subject expertise and potentially result from differences in both functional and structural connectivity. Hum Brain Mapp 37:4454-4471, 2016. © 2016 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc. © 2016 The Authors Human Brain Mapping Published by Wiley Periodicals

Efficiency of application of special exercises and exercises with the use of baseball pitching machine

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Agapov D.V.

2012-01-01

Full Text Available Efficiency of the approach on making up coordination capabilities and technical tactical performances in baseball is confirmed. 100 boys (age 12-14 years take part in experiment. Relative analysis of a level of development of coordination capabilities and technical tactical readiness of baseball players is carried out. The level of development of technical readiness after experiment under the program «pitch, hit and run» is taped. The frame of special exercises with usage of colour balls is featured. Dynamics of hits for baseball players on a flying ball is presented. The approach in modelling of requirements of competitive activity is developed.

Location, Location, Location: The Transmission of Racist Ideology in Baseball Cards

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Regoli, Robert M.; Hewitt, John D.; Munoz, Robert, Jr.; Regoli, Adam M.

2004-01-01

While on the surface baseball cards may appear to be a mundane object of child's play, they are precious tools for examining U.S. society. Baseball cards not only hold a wealth of information regarding the players they feature they also reveal much about the state of society at the time of their production and the individuals who collect them. In…

BASEBALL THROWING MECHANICS AS THEY RELATE TO PATHOLOGY AND PERFORMANCE - A REVIEW

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Rod Whiteley

2007-03-01

Full Text Available It is a commonly held perception amongst biomechanists, sports medicine practitioners, baseball coaches and players, that an individual baseball player's style of throwing or pitching influences their performance and susceptibility to injury. With the results of a series of focus groups with baseball managers and pitching coaches in mind, the available scientific literature was reviewed regarding the contribution of individual aspects of pitching and throwing mechanics to potential for injury and performance. After a discussion of the limitations of kinematic and kinetic analyses, the individual aspects of pitching mechanics are discussed under arbitrary headings: Foot position at stride foot contact; Elbow flexion; Arm rotation; Arm horizontal abduction; Arm abduction; Lead knee position; Pelvic orientation; Deceleration-phase related issues; Curveballs; and Teaching throwing mechanics. In general, popular opinion of baseball coaching staff was found to be largely in concordance with the scientific investigations of biomechanists with several notable exceptions. Some difficulties are identified with the practical implementation of analyzing throwing mechanics in the field by pitching coaches, and with some unquantified aspects of scientific analyses

Craniomaxillofacial fractures during recreational baseball and softball.

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Bak, Matthew J; Doerr, Timothy D

2004-10-01

Baseball and softball are leading causes of sports-related facial trauma in the United States. We review our institutional experience (Strong Memorial Hospital, Rochester, NY) with these injuries and discuss measures to reduce their incidence. We review our institutions experience with facial fractures sustained during the course of a softball or baseball game over a 12-year period. A total of 38 patients were identified and medical records analyzed for patient demographics, type of impact, and fracture location. The male-to-female ratio was 3.2:1; mean age was 24.2 years, with 17 (45%) of the injuries occurring in the pediatric population. The majority of the injuries were caused by direct impact with the ball (68%), while player-player collisions (18%) and impact from a swung bat (13%) were responsible for the remaining injuries. There were a total of 39 fractures; 18 fractures (46%) involved the midface (level 2), skull (level 1) fractures accounted for 12 (31%), while 9 (23%) were mandibular (level 3) fractures. With 68% of the injuries resulting from a ball impact, we endorse the recommendations of the Consumer Product Safety Commission for the use of low-impact National Operating Committee on Standards for Athletic Equipment-approved baseballs and softballs for youth and recreational leagues.

Drive theory and home run milestones in baseball: an historical analysis.

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Goldschmied, Nadav; Harris, Michael; Vira, Damien; Kowalczyk, Jason

2014-02-01

The purpose of this investigation was to test whether the performance of the home run hitters in Major League Baseball adhered to predictions of Drive Theory. 24 baseball players who have hit at least 505 home runs were included in the sample. Their performance was assessed around the time in which they reached a significant home run career milestone, operationalized as either 500 or 600 home runs, or surpassing the league's home run record. As predicted, the players were found to require significantly more at-bats to complete the 5 home runs before the milestone, when stress was assumed to be mounting, than the 5 home runs after the milestone. In contrast, those players who reached the personal landmark from 1988 (the suspected commencement of the so-called "Steroid Era") onwards required the same number of at-bats before and after the milestone.

The Kinetics of Swinging a Baseball Bat.

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Crisco, Joseph J; Osvalds, Nikolas J; Rainbow, Michael J

2018-04-13

The purpose of this study was to compute the three-dimensional kinetics required to swing three youth baseball bats of varying moments of inertia (MOI). 306 swings by 22 male players (13-18 yrs.) were analyzed. Inverse dynamics with respect to the batter's hands were computed given the known kinematics and physical properties of the bats. We found that peak force increased with larger bat MOI and was strongly correlated with bat tip speed. In contrast, peak moments were weakly correlated with bat MOI and bat tip speed. Throughout the swing, the force applied to the bat was dominated by a component aligned with the long axis of the bat and directed away from the bat knob, while the moment applied to the bat was minimal until just prior to ball impact. These results indicate that players act to mostly "pull" the bat during their swing until just prior to ball impact, at which point they rapidly increase the moment on the bat. This kinetic analysis provides novel insight into the forces and moments used to swing baseball bats.

Using Statistical Process Control Charts to Identify the Steroids Era in Major League Baseball: An Educational Exercise

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Hill, Stephen E.; Schvaneveldt, Shane J.

2011-01-01

This article presents an educational exercise in which statistical process control charts are constructed and used to identify the Steroids Era in American professional baseball. During this period (roughly 1993 until the present), numerous baseball players were alleged or proven to have used banned, performance-enhancing drugs. Also observed…

How Major League Baseball Clubs Have Commercialized Their Investment in Japanese Top Stars

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Isao Okada; Stephen A. Greyser

2013-01-01

When a Major League Baseball club signs a Japanese star player, it obviously tries to commercialize its investment in the player. The initial focus is on home attendance (ticket sales) and television audiences, plus merchandise sales. These elements are similar to those considered for any high-performing players. However, for Japanese stars, there is also the potential to attract significant fandom from the local Japanese community. This represents an opportunity for truly incremental local r...

Swing Weights of Baseball and Softball Bats

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Russell, Dan

2010-01-01

Baseball and softball bats are sold according to length in inches and weight in ounces. Much to the consternation of players buying new bats, however, not all bats that weigh the same swing the same. The reason for this has to do with moment of inertia of the bat about a pivot point on the handle, or what the sporting goods industry refers to as…

Risk Stratification for Ulnar Collateral Ligament Injury in Major League Baseball Players: A Retrospective Study From 2007 to 2014.

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DeFroda, Steven F; Kriz, Peter K; Hall, Amber M; Zurakowski, David; Fadale, Paul D

2016-02-01

Ulnar collateral ligament (UCL) injury has become increasingly common in Major League Baseball (MLB) players in recent years. There is a significant difference in preinjury fastball velocity between MLB pitchers with tears and matched controls without UCL injury. Pitchers with injuries are throwing harder and getting injured earlier in their MLB careers. Cohort study; Level of evidence, 3. From 2007 to 2014, a total of 170 documented UCL injuries (156 pitchers, 14 position players) occurred in MLB. Inclusion criteria for this study consisted of any player who tore his UCL in MLB during this time frame. There were 130 regular-season tears (April-September). From this group, 118 players who pitched more than 100 innings prior to tear were matched to subjects with no tear and were compared using a logistic regression analysis. A subgroup of "early tear" players who threw less than 100 career innings (n = 37) was also identified and compared with the larger tear group using a logistic regression analysis. Of the 130 tears that occurred during the regular season, a significantly larger number (62%) occurred in the first 3 months (P = .011). The rate of UCL tears per MLB player (P = .001) was statistically significant. In the group of 118 matched tears, the mean fastball velocity was greater in the tear group (91.7 mph) compared with the control group (91.0 mph; P = .014). Furthermore, relief pitchers made up a greater percentage of the early tear group (<100 innings) compared with the later tear group (P = .011). Sixteen of the 170 UCL tears (9.4%) were recurrent tears, with 5 of 16 experiencing both tear and retear within the past 4 years. There is a statistically significant difference in the mean fastball velocity of pitchers who injure their UCL. Small increases in pitcher fastball velocity are a main contribution to the increased rate of tear in MLB. In addition, there has been an increased incidence of injury in the first 3 months of the season. Finally, early

Evaluation of safety balls and faceguards for prevention of injuries in youth baseball.

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Marshall, Stephen W; Mueller, Frederick O; Kirby, Daniel P; Yang, Jingzhen

2003-02-05

Safety balls and faceguards are widely used in youth baseball, but their effectiveness in reducing injury is unknown. To evaluate the association of the use of faceguards and safety balls and injuries in youth baseball. Ecological study using a national database of compensated insurance claims maintained by Little League Baseball Incorporated, combined with data on the number of participants in Little League and data from a census of protective equipment usage for youth aged 5 to 18 years participating in Little League Baseball in the United States during 1997-1999. Rate of injury and injury rate ratio comparing users with nonusers of protective equipment. A total of 6 744 240 player-seasons of follow-up and 4233 compensated injury claims were available for analysis. The absolute incidence of compensated injury per 100 000 player-seasons was 28.02 (95% confidence interval [CI], 26.76-29.29) for ball-related injury and 2.71 (95% CI, 2.32-3.11) for facial injury. Overall, use of safety balls was associated with a reduced risk of ball-related injury (adjusted rate ratio, 0.77; 95% CI, 0.64-0.93). This reduction was essentially due to 1 type of safety ball, known as the reduced-impact ball (adjusted rate ratio, 0.72; 95% CI, 0.57-0.91). Use of faceguards reduced the risk of facial injury (adjusted rate ratio, 0.65; 95% CI, 0.43-0.98). Metal and plastic guards appeared to be equally effective. Safety balls appeared to be more effective in the minor division (ages 7-12 years) than in the regular division (ages 9-12 years). Reduced-impact balls and faceguards were associated with a reduced risk of injury in youth baseball. These findings support increased usage of these items; however, it should be noted that the absolute incidence of injury in youth baseball is low and that these equipment items do not prevent all injuries.

Avaliação do ombro doloroso no jogador de beisebol Evaluation of painful shoulder in baseball players

Directory of Open Access Journals (Sweden)

Alberto Naoki Miyazaki

2011-04-01

Full Text Available OBJETIVO: Avaliar em jogadores de beisebol a relação entre mobilidade e força do ombro e a presença de dor. MÉTODOS: Entre abril e julho de 2009 foram avaliados 55 jogadores de beisebol pelo Grupo de Ombro e Cotovelo da Faculdade de Ciências Médicas da Santa Casa de Misericórdia de São Paulo. Todos do sexo masculino, com idade entre 15 e 33 anos (média de 21, média de três treinos por semana e tempo médio de prática da modalidade de 10 anos. RESULTADOS: 14 dos 55 atletas avaliados eram arremessadores, 20 referiram dor no arremesso. As médias de rotação lateral, medial e amplitude de movimento (ADM do ombro dominante foram de 110º, 61º e 171º, respectivamente, com diferença estatisticamente significante em relação ao membro não dominante. Arremessadores tiveram maior ganho de rotação lateral e déficit de rotação medial que os não arremessadores. Dor teve correlação estaticamente significante com ADM diminuída, maior tempo de prática da modalidade e situação de "ombro em risco". CONCLUSÃO: Foram encontradas diferenças estatisticamente significantes na mobilidade do ombro dominante com aumento da rotação lateral, diminuição da rotação medial e menor amplitude de movimento, em relação ao membro contralateral. Foram encontradas relações estatisticamente significantes entre maior ganho de rotação lateral e diminuição da rotação medial e a posição de arremessador. Houve correlação estatisticamente significante entre dor e ADM diminuída, maior tempo de prática da modalidade e situação de "ombro em risco". Existe uma tendência estatística sugerindo que os atletas com rotação medial do ombro dominante diminuída tenham relação com dor.OBJECTIVE: To assess the relationship between shoulder mobility and strength and the presence of pain among baseball players. METHODS: Between April and July 2009, 55 baseball players were assessed by the Shoulder and Elbow Group of the School of Medical

High School Rugby Players' Perception of Coaching Effectiveness

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Broodryk, Retief; van den Berg, Pieter Hendrick

2011-01-01

The aims of this study were firstly to determine the players' perceptions of their respective coaches' coaching effectiveness and secondly, determine the difference between big and small schools of the players' perceptions of their respective coaches' coaching effectiveness. Four hundred and seventy six players from 22 schools were asked to fill…

Effect of various warm-up devices on bat velocity of intercollegiate softball players.

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Szymanski, David J; Bassett, Kylie E; Beiser, Erik J; Till, Megan E; Medlin, Greg L; Beam, Jason R; Derenne, Coop

2012-01-01

Numerous warm-up devices are available for use by softball players while they are in the on-deck circle. It is difficult to know which warm-up device produces the greatest bat velocity (BV) in the batter's box for softball players because on-deck studies with these individuals are sparse. Because the majority of warm-up device research has been conducted with baseball players, the primary purpose of this study was to examine the effect of various warm-up devices on the BV of female intercollegiate softball players and compare the results with those of male baseball players. A secondary purpose was to evaluate 2 new commercially available resistance devices as warm-up aids. Nineteen Division I intercollegiate softball players (age = 19.8 ± 1.2 years, height = 167.0 ± 4.7 cm, body mass = 69.2 ± 8.6 kg, lean body mass = 49.6 ± 3.6 kg, % body fat = 27.9 ± 5.9) participated in a warm-up with 1 of 8 resistance devices on separate days. Each of the 8 testing sessions had players perform a standardized dynamic warm-up, 3 maximal dry swings mimicking their normal game swing with the assigned warm-up device, 2 comfortable dry swings with a standard 83.8-cm, 652-g (33-in., 23-oz) softball bat followed by 3 maximal game swings (20-second rest between swings) while hitting a softball off a batting tee with the same standard softball bat. Results indicated that there were no statistically significant differences in BV after using any of the 8 warm-up devices (510.3-2,721.5 g or 18-96 oz) similar to in previous baseball research. This indicates that the results for both male and female intercollegiate players are similar and that intercollegiate softball players can use any of the 8 warm-up devices in the on-deck circle and have similar BVs. However, similar to in other previous baseball research, it is not recommended that female intercollegiate softball players warm up with the popular commercial donut ring in the on-deck circle because it produced the slowest BV.

Pitch Counts in Youth Baseball and Softball: A Historical Review.

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Feeley, Brian T; Schisel, Jessica; Agel, Julie

2018-07-01

Pitching injuries are getting increased attention in the mass media. Many references are made to pitch counts and the role they play in injury prevention. The original purpose of regulating the pitch count in youth baseball was to reduce injury and fatigue to pitchers. This article reviews the history and development of the pitch count limit in baseball, the effect it has had on injury, and the evidence regarding injury rates on softball windmill pitching. Literature search through PubMed, mass media, and organizational Web sites through June 2015. Pitch count limits and rest recommendations were introduced in 1996 after a survey of 28 orthopedic surgeons and baseball coaches showed injuries to baseball pitchers' arms were believed to be from the number of pitches thrown. Follow-up research led to revised recommendations with more detailed guidelines in 2006. Since that time, data show a relationship between innings pitched and upper extremity injury, but pitch type has not clearly been shown to affect injury rates. Current surveys of coaches and players show that coaches, parents, and athletes often do not adhere to these guidelines. There are no pitch count guidelines currently available in softball. The increase in participation in youth baseball and softball with an emphasis on early sport specialization in youth sports activities suggests that there will continue to be a rise in injury rates to young throwers. The published pitch counts are likely to positively affect injury rates but must be adhered to by athletes, coaches, and parents.

Biceps tendinitis caused by an osteochondroma in the bicipital groove: a rare cause of shoulder pain in a baseball player.

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Onga, Takafumi; Yamamoto, Tetsuji; Akisue, Toshihiro; Marui, Takashi; Kurosaka, Masahiro

2005-02-01

Tendinitis of the long head of the biceps brachii muscle is commonly seen in athletes who do repetitive overhead motions. Common causes of biceps tendinitis include impingement syndrome, subluxation of the biceps tendon, and attrition tendinitis, whereas biceps tendinitis secondary to a bone neoplasm is rare. A case of biceps tendinitis caused by an osteochondroma arising in the left humeral bicipital groove in a 25-year-old male baseball player is reported. The tumor was hook-shaped, originated from the inferomedial portion of the humeral lesser tubercle, and surrounded the biceps tendon. Symptoms of increasing pain and inability to throw resulted from direct irritation of the biceps tendon by the tumor. Total excision of the tumor relieved the symptoms within 3 weeks. To our knowledge, there have been no reported cases in the English-language literature of biceps tendinitis caused by an osteochondroma.

Prospective multifactorial analysis of preseason risk factors for shoulder and elbow injuries in high school baseball pitchers.

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Shitara, Hitoshi; Kobayashi, Tsutomu; Yamamoto, Atsushi; Shimoyama, Daisuke; Ichinose, Tsuyoshi; Tajika, Tsuyoshi; Osawa, Toshihisa; Iizuka, Haku; Takagishi, Kenji

2017-10-01

To prospectively identify preseason physical factors for shoulder and elbow injuries during the season in high school baseball pitchers. The study included 105 high school baseball pitchers [median age 16 (15-17) years]. The range of motion of the shoulder (90° abducted external and internal rotation) and elbow (extension/flexion), shoulder muscle strength (abduction and prone internal and external rotation), shoulder and elbow laxity, horizontal flexion, and scapular dyskinesis were assessed. After the season, the participants completed questionnaires regarding shoulder and/or elbow injuries, with injury defined as an inability to play for ≥1 week due to elbow/shoulder problems. The results of two groups (injured and noninjured) were compared using t tests and Chi-square analyses. Stepwise forward logistic regression models were developed to identify risk factors. Twenty-one injuries were observed. In univariate analysis, 90° abducted internal rotation and total arc of the dominant shoulder and the ratio of prone external rotation in the dominant to nondominant sides in the injured group were significantly less than those in the noninjured group (P = 0.02, 0.04, and 0.01, respectively). In logistic regression analysis, 90° abducted internal rotation in the dominant shoulder and prone external rotation ratio were significantly associated with injuries (P = 0.02 and 0.03, respectively). A low prone external rotation ratio and decreased 90° abducted internal rotation in the dominant shoulder in the preseason were significant risk factors for shoulder and elbow injuries in high school baseball pitchers. The results may contribute to reduce the incidence of these injuries. II.

Are professional handball players at risk for developing a glenohumeral internal rotation deficit in their dominant arm?

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Seabra, Pedro; Van Eck, Carola F; Sá, Márcia; Torres, João

2017-05-01

Overhead athletes, such as baseball players, have been shown to have adaptive changes in the shoulder range of motion (ROM) of their dominant arm. Professional handball players are a unique subtype of overhead athletes with very different demands from baseball players. The aim of this study was to determine if professional handball players demonstrate differences in shoulder ROM between their dominant and non-dominant arm and try to relate them with new variables. Fifty professional male handball players were included and completed a questionnaire regarding age at which they started to play, number of hours they practice a week, field position and arm dominance. ROM measurements were performed including forward flexion (FF), external rotation with the shoulder in abduction (ABER) and with adducted arm (ADER) and internal rotation with shoulder in abduction (IR). Statistical analysis was performed to determine differences in ROM between the dominant and non-dominant shoulder and if there is a relationship between these differences and shoulder load or field position. The dominant arm showed decreased internal rotation (47 vs. 56 degrees, p handball players with a first line position have a significant risk for developing a glenohumeral internal rotation deficit, similar to the phenomenon seen in baseball pitchers.

Rotator Interval Lesion and Damaged Subscapularis Tendon Repair in a High School Baseball Player

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Tomoyuki Muto

2015-01-01

Full Text Available In 2013, a 16-year-old baseball pitcher visited Nobuhara Hospital complaining of shoulder pain and limited range of motion in his throwing shoulder. High signal intensity in the rotator interval (RI area (ball sign, injured subscapularis tendon, and damage to both the superior and middle glenohumeral ligaments were identified using magnetic resonance imaging (MRI. Repair of the RI lesion and partially damaged subscapularis tendon was performed in this pitcher. During surgery, an opened RI and dropping of the subscapularis tendon were observed. The RI was closed in a 90° externally rotated and abducted position. To reconfirm the exact repaired state of the patient, arthroscopic examination was performed from behind. However, suture points were not visible in the >30° externally rotated position, which indicates that the RI could not be correctly repaired with the arthroscopic procedure. One year after surgery, the patient obtained full function of the shoulder and returned to play at a national convention. Surgical repair of the RI lesion should be performed in exactly the correct position of the upper extremity.

Origins of superior dynamic visual acuity in baseball players: superior eye movements or superior image processing.

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Yusuke Uchida

Full Text Available Dynamic visual acuity (DVA is defined as the ability to discriminate the fine parts of a moving object. DVA is generally better in athletes than in non-athletes, and the better DVA of athletes has been attributed to a better ability to track moving objects. In the present study, we hypothesized that the better DVA of athletes is partly derived from better perception of moving images on the retina through some kind of perceptual learning. To test this hypothesis, we quantitatively measured DVA in baseball players and non-athletes using moving Landolt rings in two conditions. In the first experiment, the participants were allowed to move their eyes (free-eye-movement conditions, whereas in the second they were required to fixate on a fixation target (fixation conditions. The athletes displayed significantly better DVA than the non-athletes in the free-eye-movement conditions. However, there was no significant difference between the groups in the fixation conditions. These results suggest that the better DVA of athletes is primarily due to an improved ability to track moving targets with their eyes, rather than to improved perception of moving images on the retina.

Origins of superior dynamic visual acuity in baseball players: superior eye movements or superior image processing.

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Uchida, Yusuke; Kudoh, Daisuke; Murakami, Akira; Honda, Masaaki; Kitazawa, Shigeru

2012-01-01

Dynamic visual acuity (DVA) is defined as the ability to discriminate the fine parts of a moving object. DVA is generally better in athletes than in non-athletes, and the better DVA of athletes has been attributed to a better ability to track moving objects. In the present study, we hypothesized that the better DVA of athletes is partly derived from better perception of moving images on the retina through some kind of perceptual learning. To test this hypothesis, we quantitatively measured DVA in baseball players and non-athletes using moving Landolt rings in two conditions. In the first experiment, the participants were allowed to move their eyes (free-eye-movement conditions), whereas in the second they were required to fixate on a fixation target (fixation conditions). The athletes displayed significantly better DVA than the non-athletes in the free-eye-movement conditions. However, there was no significant difference between the groups in the fixation conditions. These results suggest that the better DVA of athletes is primarily due to an improved ability to track moving targets with their eyes, rather than to improved perception of moving images on the retina.

Protective Equipment and Player Characteristics Associated With the Incidence of Sport-Related Concussion in High School Football Players

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McGuine, Timothy A.; Hetzel, Scott; McCrea, Michael; Brooks, M. Alison

2015-01-01

Background The incidence of sport-related concussion (SRC) in high school football is well documented. However, limited prospective data are available regarding how player characteristics and protective equipment affect the incidence of SRC. Purpose To determine whether the type of protective equipment (helmet and mouth guard) and player characteristics affect the incidence of SRC in high school football players. Design Cohort study; Level of evidence, 2. Methods Certified athletic trainers (ATs) at each high school recorded the type of helmet worn (brand, model, purchase year, and recondition status) by each player as well as information regarding players’ demographics, type of mouth guard used, and history of SRC. The ATs also recorded the incidence and days lost from participation for each SRC. Incidence of SRC was compared for various helmets, type of mouth guard, history of SRC, and player demographics. Results A total of 2081 players (grades 9–12) enrolled during the 2012 and/or 2013 football seasons (2287 player-seasons) and participated in 134,437 football (practice or competition) exposures. Of these players, 206 (9%) sustained a total of 211 SRCs (1.56/1000 exposures). There was no difference in the incidence of SRC (number of helmets, % SRC [95% CI]) for players wearing Riddell (1171, 9.1% [7.6%–11.0%]), Schutt (680, 8.7% [6.7%–11.1%]), or Xenith (436, 9.2% [6.7%–12.4%]) helmets. Helmet age and recondition status did not affect the incidence of SRC. The rate of SRC (hazard ratio [HR]) was higher in players who wore a custom mouth guard (HR = 1.69 [95% CI, 1.20–2.37], P football players. Players who had sustained an SRC within the previous 12 months were more likely to sustain an SRC than were players without a history of SRC. Sports medicine providers who work with high school football players need to realize that factors other than the type of protective equipment worn affect the risk of SRC in high school players. PMID:25060072

Physics of Baseball & Softball

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Cross, Rod

2011-01-01

This book describes the physics of baseball and softball, assuming that the reader has a background in both physics and mathematics at the high school level. The physics is explained in a conversational style, and illustrated with experimental results obtained both in the laboratory and in the field. Simple equations are also used in order to model the experimental results and to test whether the explanations are actually valid. The subject matter provides an excellent opportunity to explain physics in an interesting manner, given the universal popularity of baseball and softball as pastimes. There is also the interaction between a bat and ball, which is a classic problem in physics involving large forces, short time intervals, momentum, and energy transfer, vibration, rotation, and the different physical properties of the wood (or aluminum) of the bat, and the ball. The flight of the ball through the air is another fascinating example of physics in action, involving the effects of gravity, air resistance and...

In support of a hot hand in professional basketball and baseball.

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Shea, Stephen

2014-06-01

Recent studies have found little empirical evidence to suggest that National Basketball Association (NBA) and Major League Baseball (MLB) players have hot streaks. This has led some to suggest that hot hands do not exist and that offensive and defensive strategies adjusting to perceived hot hands are suboptimal. We study the MLB's Home Run Derby and the NBA's 3-point Shootout. When there is no defense, extended time between shots has been removed, and shot or swing selection is constant, we find evidence that player performance is nonstationary. Our results are consistent with beliefs long held by players, coaches, and fans, research on the importance of self-efficacy in sports, and studies that support the existence of hot streaks in sports with no or limited defense. © 2013 The Institute of Psychology, Chinese Academy of Sciences and Wiley Publishing Asia Pty Ltd.

Development of the Curriculum and Instructional Model for Learning the Tactical Awareness by the Each Role in the Baseball Game in the Elementary School

OpenAIRE

中井, 隆司; 宗野, 伸哉; 川島, 弘美

2006-01-01

The purpose of this study was to develop the curriculum and instructional model for learning the tactical awareness by the each role in the baseball game in the elemetary school. This baseball game' s practice composed three task games, the drill game and the teaching process for learning "tactical awareness". For analyzing the learning process and the products, four students were selected by the throwing ability. In this teaching unit, the learning process and the products were measured in t...

Trends in Revision Elbow Ulnar Collateral Ligament Reconstruction in Professional Baseball Pitchers.

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Wilson, Alexander T; Pidgeon, Tyler S; Morrell, Nathan T; DaSilva, Manuel F

2015-11-01

To determine the frequency of revision elbow ulnar collateral ligament (UCL) reconstruction in professional baseball pitchers. Data were collected on 271 professional baseball pitchers who underwent primary UCL reconstruction. Each player was evaluated retrospectively for occurrence of revision UCL reconstructive surgery to treat failed primary reconstruction. Data on players who underwent revision UCL reconstruction were compiled to determine total surgical revision incidence and revision rate by year. The incidence of early revision was analyzed for trends. Average career length after primary UCL reconstruction was calculated and compared with that of players who underwent revision surgery. Logistic regression analysis was performed to assess risk factors for revision including handedness, pitching role, and age at the time of primary reconstruction. Between 1974 and 2014, the annual incidence of primary UCL reconstructions among professional pitchers increased, while the proportion of cases being revised per year decreased. Of the 271 pitchers included in the study, 40 (15%) required at least 1 revision procedure during their playing career. Three cases required a second UCL revision reconstruction. The average time from primary surgery to revision was 5.2 ± 3.2 years (range, 1-13 years). The average length of career following primary reconstruction for all players was 4.9 ± 4.3 years (range, 0-22 years). The average length of career following revision UCL reconstruction was 2.5 ± 2.4 years (range, 0-8 years). No risk factors for needing revision UCL reconstruction were identified. The incidence of primary UCL reconstructions among professional pitchers is increasing; however, the rate of primary reconstructions requiring revision is decreasing. Explanations for the decreased revision rate may include improved surgical technique and improved rehabilitation protocols. Therapeutic IV. Copyright © 2015 American Society for Surgery of the Hand. Published by

Impact locations and concussion outcomes in high school football player-to-player collisions.

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Kerr, Zachary Y; Collins, Christy L; Mihalik, Jason P; Marshall, Stephen W; Guskiewicz, Kevin M; Comstock, R Dawn

2014-09-01

Little research has examined concussion outcomes in terms of impact location (ie, the area on the head in which the impact occurred). This study describes the epidemiology of concussions resulting from player-to-player collision in high school football by impact location. National High School Sports-Related Injury Surveillance Study data (2008/2009-2012/2013) were analyzed to calculate rates and describe circumstances of football concussion (eg, symptomology, symptom resolution time, return to play) resulting from player-to-player collisions by impact location (ie, front-, back-, side-, and top-of-the-head). Most concussions resulting from player-to-player collisions occurred from front-of-the-head (44.7%) and side-of-the-head (22.3%) impacts. Number of symptoms reported, prevalence of reported symptoms, symptom resolution time, and length of time to return to play were not associated with impact location. However, a larger proportion of football players sustaining concussions from top-of-the-head impacts experienced loss of consciousness (8.0%) than those sustaining concussions from impacts to other areas of the head (3.5%) (injury proportion ratio 2.3; 95% confidence interval 1.2-4.2; P = .008). Players had their head down at the time of impact in a higher proportion of concussions caused by top-of-the-head impacts (86.4%) than concussions from impacts to other areas of the head (24.0%) (injury proportion ratio 3.6; 95% confidence interval 3.2-4.0; P impact location. Recommended strategies for reducing the proportion of top-of-the-head impacts include improved education regarding tackling with proper "head-up" technique. Copyright © 2014 by the American Academy of Pediatrics.

How Do Batters Use Visual, Auditory, and Tactile Information about the Success of a Baseball Swing?

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Gray, Rob

2009-01-01

Bat/ball contact produces visual (the ball leaving the bat), auditory (the "crack" of the bat), and tactile (bat vibration) feedback about the success of the swing. We used a batting simulation to investigate how college baseball players use visual, tactile, and auditory feedback. In Experiment 1, swing accuracy (i.e., the lateral separation…

Comparison of physical activities of female football players in junior high school and high school.

Science.gov (United States)

Inoue, Yuri; Otani, Yoshitaka; Takemasa, Seiichi

2017-08-01

[Purpose] This study aimed to compare physical activities between junior high school and high school female football players in order to explain the factors that predispose to a higher incidence of sports injuries in high school female football players. [Subjects and Methods] Twenty-nine female football players participated. Finger floor distance, the center of pressure during single limb stance with eyes open and closed, the 40-m linear sprint time, hip abduction and extension muscle strength and isokinetic knee flexion and extension peak torque were measured. The modified Star Excursion Balance Test, the three-steps bounding test and three-steps hopping tests, agility test 1 (Step 50), agility test 2 (Forward run), curl-up test for 30 seconds and the Yo-Yo intermittent recovery test were performed. [Results] The high school group was only significantly faster than the junior high school group in the 40-m linear sprint time and in the agility tests. The distance of the bounding test in the high school group was longer than that in the junior high school group. [Conclusion] Agility and speed increase with growth; however, muscle strength and balance do not develop alongside. This unbalanced development may cause a higher incidence of sports injuries in high school football players.

Protective equipment and player characteristics associated with the incidence of sport-related concussion in high school football players: a multifactorial prospective study.

Science.gov (United States)

McGuine, Timothy A; Hetzel, Scott; McCrea, Michael; Brooks, M Alison

2014-10-01

The incidence of sport-related concussion (SRC) in high school football is well documented. However, limited prospective data are available regarding how player characteristics and protective equipment affect the incidence of SRC. To determine whether the type of protective equipment (helmet and mouth guard) and player characteristics affect the incidence of SRC in high school football players. Cohort study; Level of evidence, 2. Certified athletic trainers (ATs) at each high school recorded the type of helmet worn (brand, model, purchase year, and recondition status) by each player as well as information regarding players' demographics, type of mouth guard used, and history of SRC. The ATs also recorded the incidence and days lost from participation for each SRC. Incidence of SRC was compared for various helmets, type of mouth guard, history of SRC, and player demographics. A total of 2081 players (grades 9-12) enrolled during the 2012 and/or 2013 football seasons (2287 player-seasons) and participated in 134,437 football (practice or competition) exposures. Of these players, 206 (9%) sustained a total of 211 SRCs (1.56/1000 exposures). There was no difference in the incidence of SRC (number of helmets, % SRC [95% CI]) for players wearing Riddell (1171, 9.1% [7.6%-11.0%]), Schutt (680, 8.7% [6.7%-11.1%]), or Xenith (436, 9.2% [6.7%-12.4%]) helmets. Helmet age and recondition status did not affect the incidence of SRC. The rate of SRC (hazard ratio [HR]) was higher in players who wore a custom mouth guard (HR = 1.69 [95% CI, 1.20-2.37], P football players. Players who had sustained an SRC within the previous 12 months were more likely to sustain an SRC than were players without a history of SRC. Sports medicine providers who work with high school football players need to realize that factors other than the type of protective equipment worn affect the risk of SRC in high school players. © 2014 The Author(s).

Baseball Physics: A New Mechanics Lab

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Wagoner, Kasey; Flanagan, Daniel

2018-05-01

The game of baseball provides an interesting laboratory for experimenting with mechanical phenomena (there are many good examples in The Physics Teacher, available on Professor Alan Nathan's website, and discussed in Physics of Baseball & Softball). We have developed a lab, for an introductory-level physics course, that investigates many of these phenomena. The lab uses inexpensive, readily available equipment such as wooden baseball bats, baseballs, and actual Major League Baseball data. By the end of the lab, students have revisited many concepts they learned earlier in the semester and come away with an understanding of how to put seemingly disparate ideas together to analyze a fun sport.

Detrending career statistics in professional baseball: Accounting for the steroids era and beyond

OpenAIRE

Petersen, Alexander M.; Penner, Orion; Stanley, H. Eugene

2010-01-01

There is a long standing debate over how to objectively compare the career achievements of professional athletes from different historical eras. Developing an objective approach will be of particular importance over the next decade as Major League Baseball (MLB) players from the "steroids era" become eligible for Hall of Fame induction. Here we address this issue, as well as the general problem of comparing statistics from distinct eras, by detrending the seasonal statistics of professional b...

High School Football Players and Their Coaches: A Qualitative Study of Their Relationships

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Skaza, Robert J.

2014-01-01

This basic qualitative study of high school football coach-player relationships explores the players' perceptions of these relationships, specifically the perceptions the players have of how these relationships influenced their lives. This study allowed the researcher to examine the characteristics of high school football coaches as they relate to…

Baseball and softball.

Science.gov (United States)

Rice, Stephen G; Congeni, Joseph A

2012-03-01

Baseball and softball are among the most popular and safest sports in which children and adolescents participate. Nevertheless, traumatic and overuse injuries occur regularly, including occasional catastrophic injury and even death. Safety of the athlete is a constant focus of attention among those responsible for modifying rules. Understanding the stresses placed on the arm, especially while pitching, led to the institution of rules controlling the quantity of pitches thrown in youth baseball and established rest periods between pitching assignments. Similarly, field maintenance and awareness of environmental conditions as well as equipment maintenance and creative prevention strategies are critically important in minimizing the risk of injury. This statement serves as a basis for encouraging safe participation in baseball and softball. This statement has been endorsed by the Canadian Paediatric Society.

Systematic Review of Traumatic Brain Injuries in Baseball and Softball: A Framework for Prevention.

Science.gov (United States)

Cusimano, Michael D; Zhu, Alice

2017-01-01

Traumatic brain injuries (TBIs) are an important public health challenge. The classification of baseball and softball as low contact sports and their association with extremity injuries cause individuals to overlook the risk of TBI in baseball and softball. To summarize our knowledge of the epidemiology and risk factors of TBIs associated with baseball and softball with an aim to better design and implement preventive strategies. A search algorithm containing keywords that were synonymous to the terms "TBI," "baseball" was applied to the following nine databases: MEDLINE, Scopus, PubMed, EMBASE, CINAHL, Healthstar, PsychINFO, AMED, Cochrane library. Cited reference lists of identified articles were also consulted yielding a total of eighty-eight articles for full review. The search was concluded on November 14, 2016. The level of evidence was evaluated according to the guidelines from Strengthening the Reporting of Observational Studies in Epidemiology statement. Twenty-nine articles published between 2000 and 2016 met the criteria for analysis. Collectively, they examined the years 1982-2015 and identified 242,731 baseball-and softball-related TBIs. The most explored outcome of TBI was concussion. The average injury rate per 1,000 athletic exposures was 0.13 (range 0.03-0.46). The most common mechanism of injury was being struck by bat for younger players and being struck by ball for older athletes (adolescent and beyond). Rates of TBI were on average 4.17 times greater in games compared to practices. Females were on average 2.04 times more likely to sustain a TBI than males. Severity of TBIs varied considerably from mild and returning to the field on the same day, to immediate death. Generally, there is poor compliance with helmet use and return-to-play post-concussion guidelines. An increase TBI rates was observed over time. Multifaceted preventive strategies must be implemented to reduce the frequency and burden of these injuries. It is difficult to compare the

Editorial Commentary: Changing Times in Sports Biomechanics: Baseball Pitching Injuries and Emerging Wearable Technology.

Science.gov (United States)

Fleisig, Glenn S

2018-03-01

Research has shown relations between amount of baseball pitching and overuse injuries, as well as between poor mechanics and high loads on the elbow and shoulder. However, overuse injuries continue to be a problem from youth to professional sports. Emerging wearable technology may enable players, parents, coaches, leagues, and clinicians to monitor biomechanics during competition and training, reducing the risk of serious injury. Copyright © 2017 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

The Flight of a Baseball

Science.gov (United States)

Nathan, Alan

2010-03-01

The trajectory of a baseball moving through the air is very different from the one we teach in our introductory classes in which the only force is that due to gravity. In reality, the aerodynamic drag force (which retards the motion) and the Magnus force on a spinning baseball (which causes the ball to curve) play very important roles that are crucial to many of the subtleties of the game. These forces are governed by three phenomenological quantities: the coefficients of drag, lift, and moment, the latter determining the spin decay time constant. In past years, these quantities were studied mainly in wind tunnel experiments, whereby the forces on the baseball are measured directly. More recently, new tools have been developed that focus on measuring accurate baseball trajectories, from which the forces can be inferred. These tools include high-speed motion analysis, video tracking (the so-called PITCHf/x and HITf/x systems), and Doppler radar tracking via the TrackMan system. In this talk, I will discuss how these new tools work, what they are teaching us about baseball aerodynamics, and how they have the potential to revolutionize the analysis of the game itself.

On the potential of a chemical Bonds: Possible effects of steroids on home run production in baseball

Science.gov (United States)

Tobin, R. G.

2008-01-01

In recent years several baseball players have hit a remarkable number of home runs, and there has been speculation that their achievements were enhanced by the use of anabolic steroids. Basic mechanics and physiology, combined with simple but reasonable models, show that steroid use by a player who is already highly skilled could produce such dramatic increases in home run production. Because home runs are relatively rare events on the tail of a batter's range distribution, even modest changes in bat speed can increase the proportion of batted balls that result in home runs by 50-100%. The possible effect of steroid use by pitchers is briefly considered.

MR imaging of the elbow in baseball pitchers

Energy Technology Data Exchange (ETDEWEB)

Ouellette, Hugue; Bredella, Miriam; Palmer, William E.; Torriani, Martin [Massachusetts General Hospital, Division of Musculoskeletal Radiology, Boston, MA (United States); Labis, John [Methodist Hospital, Houston, TX (United States)

2008-02-15

Baseball pitcher throwing biomechanics are important to understanding the pathophysiology and magnetic resonance (MR) imaging appearances of injuries in baseball pitchers. Baseball pitchers experience repetitive excessive valgus forces at the elbow. Typical injuries are secondary to medial joint distraction, lateral joint compression, and rotatory forces at the olecranon. MR imaging is useful for evaluation of the elbow in baseball pitchers. (orig.)

Relative Age Effect and Academic Timing in American Junior College Baseball.

Science.gov (United States)

Beals, Thomas C; Furtado, Ovande; Fontana, Fabio E

2018-02-01

Previous research has shown that older athletes within age groupings are often perceived to be more talented simply due to advanced maturity, leading to biased selection in higher levels of sports competition, now commonly termed relative age effect (RAE). This study's goals were to determine whether (a) RAE influenced the selection of junior college baseball participants and (b) academic timing ( Glamser & Marciani, 1992 ), in which academic status determines age groupings more than strict age guidelines for college sports, influenced the formation of RAE. Participants were 150 junior college baseball players. Our results showed that RAE was only a significant factor, comparing the birth distribution of participants born before and after the midpoint of the participation year, when academic timing was also a factor in determining age groupings. In addition, the birth rate distribution, though not significantly different than expected, was greater only when those participants born during the expected participation year were included. The results of this study indicate that RAE could bear more influence among American student-athletes than was previously reported in that RAE in conjunction with academic timing does influence the selection of collegiate athletes.

Systematic Review of Traumatic Brain Injuries in Baseball and Softball: A Framework for Prevention

Directory of Open Access Journals (Sweden)

Michael D. Cusimano

2017-10-01

Full Text Available BackgroundTraumatic brain injuries (TBIs are an important public health challenge. The classification of baseball and softball as low contact sports and their association with extremity injuries cause individuals to overlook the risk of TBI in baseball and softball.PurposeTo summarize our knowledge of the epidemiology and risk factors of TBIs associated with baseball and softball with an aim to better design and implement preventive strategies.MethodsA search algorithm containing keywords that were synonymous to the terms “TBI,” “baseball” was applied to the following nine databases: MEDLINE, Scopus, PubMed, EMBASE, CINAHL, Healthstar, PsychINFO, AMED, Cochrane library. Cited reference lists of identified articles were also consulted yielding a total of eighty-eight articles for full review. The search was concluded on November 14, 2016. The level of evidence was evaluated according to the guidelines from Strengthening the Reporting of Observational Studies in Epidemiology statement.ResultsTwenty-nine articles published between 2000 and 2016 met the criteria for analysis. Collectively, they examined the years 1982–2015 and identified 242,731 baseball-and softball-related TBIs. The most explored outcome of TBI was concussion. The average injury rate per 1,000 athletic exposures was 0.13 (range 0.03–0.46. The most common mechanism of injury was being struck by bat for younger players and being struck by ball for older athletes (adolescent and beyond. Rates of TBI were on average 4.17 times greater in games compared to practices. Females were on average 2.04 times more likely to sustain a TBI than males. Severity of TBIs varied considerably from mild and returning to the field on the same day, to immediate death. Generally, there is poor compliance with helmet use and return-to-play post-concussion guidelines. An increase TBI rates was observed over time. Multifaceted preventive strategies must be implemented to reduce the frequency and

Multiple Past Concussions in High School Football Players

Science.gov (United States)

Brooks, Brian L.; Mannix, Rebekah; Maxwell, Bruce; Zafonte, Ross; Berkner, Paul D.; Iverson, Grant L.

2017-01-01

Background There is increasing concern about the possible long-term effects of multiple concussions, particularly on the developing adolescent brain. Whether the effect of multiple concussions is detectable in high school football players has not been well studied, although the public health implications are great in this population. Purpose To determine if there are measureable differences in cognitive functioning or symptom reporting in high school football players with a history of multiple concussions. Study Design Cross-sectional study; Level of evidence, 3. Methods Participants included 5232 male adolescent football players (mean [±SD] age, 15.5 ± 1.2 years) who completed baseline testing between 2009 and 2014. On the basis of injury history, athletes were grouped into 0 (n = 4183), 1 (n = 733), 2 (n = 216), 3 (n = 67), or ≥4 (n = 33) prior concussions. Cognitive functioning was measured by the Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) battery, and symptom ratings were obtained from the Post-Concussion Symptom Scale. Results There were no statistically significant differences between groups (based on the number of reported concussions) regarding cognitive functioning. Athletes with ≥3 prior concussions reported more symptoms than did athletes with 0 or 1 prior injury. In multivariate analyses, concussion history was independently related to symptom reporting but less so than developmental problems (eg, attention or learning problems) or other health problems (eg, past treatment for psychiatric problems, headaches, or migraines). Conclusion In the largest study to date, high school football players with multiple past concussions performed the same on cognitive testing as those with no prior concussions. Concussion history was one of several factors that were independently related to symptom reporting. PMID:27474382

A study of wood baseball bat breakage

Science.gov (United States)

Patrick Drane; James Sherwood; Renzo Colosimo; David Kretschmann

2012-01-01

Over the span of three months in 2008, 2232 baseball bats broke while being used during Major League Baseball (MLB) games; of which 756 were classified as Multi Piece Failures (MPFs). This rate of failure motivated Major League Baseball to explore options for potential changes in the bat regulations to reduce the rate. After a study of the information that could be...

High School Football Players Use Their Helmets to Tackle Other Players Despite Knowing the Risks.

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Kuriyama, Andrew M; Nakatsuka, Austin S; Yamamoto, Loren G

2017-03-01

There is greater attention to head-related injuries and concussions in American football. The helmet's structural safety and the way that football players use their helmets are important in preventing head injuries. Current strategies include penalizing players for high-risk behavior such as leading with their helmet or hitting an opposing player above the shoulder. Passive strategies include helmet modification to better protect the head of the players or to change the playing style of the players. Hawai'i high school varsity football players were surveyed to determine how they use their helmets and how a new helmet design would affect their style of play. One hundred seventy-seven surveys were completed; 79% said that they used their helmet to hit an opposing player during a tackle and 46% said they made this contact intentionally. When asked about modifying helmets with a soft material on the outside, 48% said they thought putting a soft cover over a regular helmet would protect their head better. However, many participants said that putting a soft cover over their regular helmet was a bad idea for various reasons. Most young football players use their helmets to block or tackle despite being taught they would be penalized or potentially injured if they did so. By gaining a better understanding of why and how players use their helmets and how they would respond to new helmet designs, steps can be taken to reduce head injuries for all levels of play.

Epidemiology of injuries in female high school soccer players ...

African Journals Online (AJOL)

Background: Sport is a compulsory activity in schools in South Africa. Female learners participating in soccer are more vulnerable to injuries than males. Objective: This study determined the epidemiology of injuries in female high school soccer players. Methods: A cross sectional survey captured the epidemiology of ...

Variations in Star Excursion Balance Test Performance Between High School and Collegiate Football Players.

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McCann, Ryan S; Kosik, Kyle B; Beard, Megan Q; Terada, Masafumi; Pietrosimone, Brian G; Gribble, Phillip A

2015-10-01

The Star Excursion Balance Test (SEBT) is a reliable inexpensive tool used to assess dynamic postural control deficits and efficacy in the prediction of musculoskeletal injuries, but with little previous consideration for performance differences across age and skill levels. The purpose of this study was to examine differences in SEBT scores between high school and collegiate football players. Three-hundred eighteen high school football players and 180 National Collegiate Athletic Association Division I collegiate football players volunteered to participate. Star Excursion Balance Test scores were obtained bilaterally for anterior (ANT), posterolateral (PL), and posteromedial (PM) directions, and for an overall composite (COMP) score. The mean of 3 trials from each leg was normalized to stance leg length and presented as a percentage score. Bilaterally averaged scores were compared between high school and collegiate football players using separate independent t-tests. A multiple linear backward regression determined the amount of variance in SEBT scores explained by age, mass, and height. Compared with collegiate athletes, high school athletes had lower PL (72.8 ± 11.4% vs. 77.1 ± 10.2%; p football players.

The Epidemiology of Overuse Conditions in Youth Football and High School Football Players.

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Morris, Kevin; Simon, Janet E; Grooms, Dustin R; Starkey, Chad; Dompier, Thomas P; Kerr, Zachary Y

2017-10-01

  High-intensity sport training at the youth level has led to increased concern for overuse conditions. Few researchers have examined overuse conditions in youth sports.   To examine the rates, risks, and distributions of overuse conditions between youth and high school football players.   Descriptive epidemiologic study.   Youth and high school football teams.   The Youth Football Safety Study (YFSS) investigated youth football athletes from age 5 to 14 years. The National Athletic Treatment, Injury and Outcomes Network (NATION) focused on high school football athletes 14 to 18 years old. The YFSS data consisted of 210 team-seasons, and the NATION data consisted of 138 team-seasons.   Athletic trainers collected football injury and exposure data during the 2012 and 2013 seasons. Injury rates, risks, and distributions were calculated, with injury rate ratios, risk ratios, and injury proportion ratios with 95% confidence intervals (CIs) comparing youth and high school football players.   The YFSS reported 1488 injuries, of which 53 (3.6%) were overuse conditions. The NATION reported 12 013 injuries, of which 339 (2.8%) were overuse conditions. The overuse condition rate did not differ between high school and youth football (3.93 versus 3.72/10 000 athlete-exposures; injury rate ratio = 1.06; 95% CI = 0.79, 1.41). However, the 1-season risk of overuse condition was higher in high school than in youth football players (2.66% versus 1.05%; risk ratio = 2.53; 95% CI = 1.84, 3.47). Compared with high school football players, youth football players had greater proportions of overuse conditions that were nontime loss (ie, football players. However, differences existed between the 2 levels of competition. Although additional research on the incidence of overuse conditions across all youth and high school sports is needed, these findings may highlight the need for programming that is specific to competition level.

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

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Freeston, Jonathan L; Carter, Thomas; Whitaker, Gary; Nicholls, Owen; Rooney, Kieron B

2016-06-01

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 velocity and medicine ball chest pass (MB CP) distance (r = 0.67; p 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

Birth order and risk taking in athletics: a meta-analysis and study of major league baseball.

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Sulloway, Frank J; Zweigenhaft, Richard L

2010-11-01

According to expectations derived from evolutionary theory, younger siblings are more likely than older siblings to participate in high-risk activities. The authors test this hypothesis by conducting a meta-analysis of 24 previous studies involving birth order and participation in dangerous sports. The odds of laterborns engaging in such activities were 1.48 times greater than for firstborns (N = 8,340). The authors also analyze performance data on 700 brothers who played major league baseball. Consistent with their greater expected propensity for risk taking, younger brothers were 10.6 times more likely to attempt the high-risk activity of base stealing and 3.2 times more likely to steal bases successfully (odds ratios). In addition, younger brothers were significantly superior to older brothers in overall batting success, including two measures associated with risk taking. As expected, significant heterogeneity among various performance measures for major league baseball players indicated that older and younger brothers excelled in different aspects of the game.

Baseball Physics: A New Mechanics Lab

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Wagoner, Kasey; Flanagan, Daniel

2018-01-01

The game of baseball provides an interesting laboratory for experimenting with mechanical phenomena (there are many good examples in "The Physics Teacher," available on Professor Alan Nathan's website, and discussed in "Physics of Baseball & Softball"). We have developed a lab, for an introductory-level physics course, that…

Baseball and society in the Caribbean

Directory of Open Access Journals (Sweden)

Andrew Zimbalist

1994-01-01

Full Text Available [First paragraph] The Tropic of Baseball: Baseball in the Dominican Republic. Rob Ruck. Westport CT: Meckler, 1991. x + 205 pp. (Cloth n.p. Trading with the Enemy: A Yankee Travels Through Castro's Cuba. Tom Miller. New York: Atheneum, 1992. x + 338 pp. (Cloth US$ 24.00 Read Bart Giamatti's Take Time for Paradise (1989 or any of the other grand old game sentimentalists and you'11 discover that baseball somehow perfectly reflects the temperament of U.S. culture. This match, in turn, accounts for basebali's enduring and penetrating popularity in the United States. Read Ruck and Miller and you'11 learn that baseball is more popular and culturally dominant in the Dominican Republic and Cuba than it is to the north. The suppressed syllogism affirms that U.S. and Caribbean cultures hold intimate similarities. If that is true, this Caribbeanist has been out to lunch; then again, no one ever accused economists of having acute cultural sensibilities.

Mental skills of South African male high school rugby players ...

African Journals Online (AJOL)

The aim of this study was to establish preliminary South African high school rugby norms for the BMSQ. The sample consisted of 152 male high school rugby players from two schools in the Ethekwini region. Preliminary norms are presented in the form of means and standard deviations. Results are compared with those of ...

Baseball and softball injuries.

Science.gov (United States)

Wang, Quincy

2006-05-01

Baseball and softball injuries can be a result of both acute and overuse injuries. Soft tissue injuries include contusions, abrasions, and lacerations. Return to play is allowed when risk of further injury is minimized. Common shoulder injuries include those to the rotator cuff, biceps tendon, and glenoid labrum. Elbow injuries are common in baseball and softball and include medial epicondylitis, ulnar collateral ligament injury, and osteochondritis dissecans. Typically conservative treatment with relative rest, medication, and a rehabilitation program will allow return to play. Surgical intervention may be needed for certain injuries or conservative treatment failure.

Getting Hit by Pitch in Professional Baseball: Analysis of Injury Patterns, Risk Factors, Concussions, and Days Missed for Batters.

Science.gov (United States)

Camp, Christopher L; Wang, Dean; Sinatro, Alec S; D'Angelo, John; Coleman, Struan H; Dines, Joshua S; Fealy, Stephen; Conte, Stan

2018-05-01

Although batters are frequently hit by pitch (HBP) in baseball, the effect of HBP injuries remains undefined in the literature. To determine the effect of HBP injuries in terms of time out of play, injury patterns resulting in the greatest time out of play, and the value of protective gear such as helmets and elbow pads. Descriptive laboratory study. Based on the Major League Baseball (MLB) Health and Injury Tracking System, all injuries to batters HBP during the 2011-2015 MLB and Minor League Baseball (MiLB) seasons were identified and analyzed. Video analysis was performed on all HBP events from the 2015 MLB season. Multivariate stepwise regression analysis was utilized to determine the predictive capacity of multiple variables (velocity, pitch type, location, etc) on injury status and severity. A total of 2920 HBP injuries resulted in 24,624 days missed (DM) over the 5 seasons. MLB HBP injuries occurred at a rate of 1 per 2554 plate appearances (1 per 9780 pitches thrown). Mean DM per injury were 8.4 (11.7 for MLB vs 8.0 for MiLB, P hit in the head/face (odds ratio, 28.7) or distal upper extremity (odds ratio, 6.4) were more likely to be injured than players HBP in other locations. Players with an unprotected elbow missed 1.7 more days (95% CI, -4.1 to 7.6) than those with an elbow protector ( P = .554) when injured after being HBP. Although HBP injuries occur infrequently in the course of normal play, they collectively represent a significant source of time out of play. The most common body regions injured include the hands/fingers and head/face, and batters hit in these locations are significantly more likely to be injured. After contusions, concussions were the most common injury diagnosis.

Use of Nutritional Supplements by High School Football and Volleyball Players

Science.gov (United States)

Mason, Melanie A; Giza, Matthew; Clayton, Lori; Lonning, Jim; Wilkerson, Rick D

2001-01-01

The known use of performance enhancing agents by athletes has occurred throughout history. In the 1960s and 1970s steroids and amphetamines were the supplements most often used. Now athletes are turning to supplements that are either natural or stimulate the release of natural hormones. The purpose of this study is to evaluate the prevalence of use of nutritional supplements among high school football and volleyball players. This study surveyed 495 male football players and 407 female volleyball players from 20 high schools in Northwest Iowa. These athletes completed anonymous surveys and returned them to their coaches. Results showed that 8% of the male athletes and 2% of the female athletes were using supplementation. Supplements used included creatine, androstiendione, HMB, amino acids, DHEA, phosphogen, weight gainer 1850, Tribulus, muscle plus, multivitamins, calcium, GABA, and Shaklee Vita Lea and Physique. PMID:11813950

The role of prism glass and postural restoration in managing a collegiate baseball player with bilateral sacroiliac joint dysfunction: a case report.

Science.gov (United States)

Robey, Jason H; Boyle, Kyndall

2013-10-01

Sacroiliac joint dysfunction (SIJD) is a condition affecting 15-30% of patients with low back pain seen in outpatient clinics. Currently there is no well-defined standard of care. The purpose of this case report is to discuss the multidisciplinary management between an athletic trainer and an optometrist for an athlete with bilateral SIJ dysfunction and a visual midline shift syndrome. A 21-year-old collegiate baseball player reported to the athletic training room, presenting with low back pain of three day duration, with tenderness over both posterior superior iliac spines (PSIS) (left > right). His pain at its worse was a 7/10 on the Numeric Pain Scale (NPS). The pain increased to the point that it limited his activities of daily living (ADLs) including getting dressed, putting on his shoes, sleeping, and getting in and out of a car. The athlete was initially treated using traditional muscle energy techniques (MET) based intervention to correct SIJD, and lumbar stabilization exercises directed by a licensed athletic trainer, as well as manipulation by a chiropractor. Three weeks of treatment did not prove to be beneficial with only a minimal (1 point on the NPRS) decrease in pain. The athlete was then referred to the head athletic trainer for consultation who prescribed orthotics, for bilateral rear-foot valgus, and Postural Restoration (PR) therapeutic exercises. After two weeks of orthotic use and PR exercises the athlete's pain decreased one additional point on the NPRS. Due to lack of progress, an optometrist was then consulted. The neuro-optometrist prescribed 2 diopter base-down prisms to be worn two hours a day, for four weeks. After four weeks of prisms and new exercises, the athlete was asymptomatic and returned to full pain-free baseball participation without further complications. The Oswestry Disability Index Questionnaire (ODI) was 48% at initial (severe disability), 40% at five weeks and 0% at discharge. The Numeric Pain Scale (NPS) score went from

Visual-Motor Control in Baseball Batting

Directory of Open Access Journals (Sweden)

Rob Gray

2011-05-01

Full Text Available With margins for error of a few milliseconds and fractions of an inch it is not surprising that hitting a baseball is considered to be one of the most difficult acts in all of sports. We have been investigating this challenging behavior using a virtual baseball batting setup in which simulations of an approaching ball, pitcher, and field are combined with real-time recording of bat and limb movements. I will present evidence that baseball batting involves variable pre-programmed control in which the swing direction and movement time (MT are set prior to the initiation of the action but can take different values from swing-to-swing. This programming process utilizes both advance information (pitch history and count and optical information picked-up very early in the ball's flight (ball time to contact TTC and rotation direction. The pre-programmed value of MT is used to determine a critical value of TTC for swing initiation. Finally, because a baseball swing is an action that is occasionally interrupted online (i.e., a “check swing”, I will discuss experiments that examine when this pre-programmed action can be stopped and the sources of optical information that trigger stopping.

Comparison of crossover and jab step start techniques for base stealing in baseball.

Science.gov (United States)

Miyanishi, Tomohisa; Endo, So; Nagahara, Ryu

2017-11-01

Base stealing is an important tactic for increasing the chance of scoring in baseball. This study aimed to compare the crossover step (CS) and jab step (JS) starts for base stealing start performance and to clarify the differences between CS and JS starts in terms of three-dimensional lower extremity joint kinetics. Twelve male baseball players performed CS and JS starts, during which their motion and the force they applied to the ground were simultaneously recorded using a motion-capture system and two force platforms. The results showed that the normalised average forward external power, the average forward-backward force exerted by the left leg, and the forward velocities of the whole body centre of gravity generated by both legs and the left leg were significantly higher for the JS start than for the CS start. Moreover, the positive work done by hip extension during the left leg push-off was two-times greater for the JS start than the CS start. In conclusion, this study has demonstrated that the jab step start may be the better technique for a base stealing start and that greater positive work produced by left hip extension is probably responsible for producing its larger forward ground reaction force.

Prevalence of and attitudes about concussion in Irish schools' rugby union players.

Science.gov (United States)

Delahunty, Sinéad E; Delahunt, Eamonn; Condon, Brian; Toomey, David; Blake, Catherine

2015-01-01

Youth rugby players represent 45.2% (N = 69,472) of the Irish rugby union playing population. The risk and consequences of concussion injury are of particular concern in these young athletes, but limited epidemiological data exists. This study investigated annual and lifetime prevalence of concussion in an Irish schoolboy rugby union cohort. An anonymous cross-sectional survey of youth rugby players was conducted. Diagnosed concussion was defined as an incident where diagnosis was confirmed by a health professional or coach. Demographics, prevalence, and attitudes to concussion were collated. Data were analyzed with descriptive statistics, chi-square test, t-tests, Mann-Whitney tests, and logistic regression. Overall, 304 youth (aged 12-18 years) responded. Lifetime prevalence of diagnosed concussion was 19.4%, with annual (2010) prevalence 6.6%. Approximately 25.4% of players with diagnosed concussions returned to play without medical advice. Internal motivation (11.8%) was the predominant factor in feeling pressure to play while concussed. A desire for further concussion education was expressed by 89.5% of participants. Reform is required to prevent and manage concussion injuries among youth players in the rugby union, including mandatory education specific to concussion and implementation of return-to-play protocols. These findings have relevance for governing bodies, coaches, clinicians, schools, parents, and rugby union players. © 2014, American School Health Association.

Project planning and project management of Baseball II-T

International Nuclear Information System (INIS)

Kozman, T.A.; Chargin, A.K.

1975-01-01

The details of the project planning and project management work done on the Baseball II-T experiment are reviewed. The LLL Baseball program is a plasma confinement experiment accomplished with a superconducting magnet in the shape of a baseball seam. Both project planning and project management made use of the Critical Path Management (CPM) computer code. The computer code, input, and results from the project planning and project management runs, and the cost and effectiveness of this method of systems planning are discussed

High Prevalence of Nontraumatic Shoulder Pain in a Regional Sample of Female High School Volleyball Athletes.

Science.gov (United States)

Frisch, Kayt E; Clark, Jacob; Hanson, Chad; Fagerness, Chris; Conway, Adam; Hoogendoorn, Lindsay

2017-06-01

Shoulder pain is becoming increasingly problematic in young players as volleyball gains popularity. Associations between repetitive motion and pain and overuse injury have been observed in other overhand sports (most notably baseball). Studies of adult athletes suggest that there is a shoulder pain and overuse problem present in volleyball players, but minimal research has been done to establish rates and causes in juvenile participants. To establish rates of shoulder pain, regardless of whether it resulted in a loss of playing time, in female high school volleyball players. A secondary goal was to determine whether high repetition volumes correlated with an increased likelihood of experiencing pain. Descriptive epidemiology study. A self-report survey focusing on the prevalence of pain not associated with a traumatic event in female high school youth volleyball players was developed. Survey questions were formulated by certified athletic trainers, experienced volleyball coaches, and biomechanics experts. Surveys were received from 175 healthy, active high school volleyball players in Iowa, South Dakota, and Minnesota. Forty percent (70/175) of active high school volleyball players remembered experiencing shoulder pain not related to traumatic injury, but only 33% (23/70) reported taking time off to recover from the pain. Based on these self-reported data, activities associated with significantly increased risk of nontraumatic shoulder pain included number of years playing competitive volleyball ( P = .01) and lifting weights out of season ( P = .001). Players who reported multiple risk factors were more likely to experience nontraumatic shoulder pain. When using time off for recovery as the primary injury criterion, we found that the incidence of shoulder pain is more than twice as high as the incidence of injury reported by previous studies. Findings also indicated that the incidence of shoulder pain may be correlated with volume of previous volleyball experience.

High Prevalence of Nontraumatic Shoulder Pain in a Regional Sample of Female High School Volleyball Athletes

Science.gov (United States)

Frisch, Kayt E.; Clark, Jacob; Hanson, Chad; Fagerness, Chris; Conway, Adam; Hoogendoorn, Lindsay

2017-01-01

Background: Shoulder pain is becoming increasingly problematic in young players as volleyball gains popularity. Associations between repetitive motion and pain and overuse injury have been observed in other overhand sports (most notably baseball). Studies of adult athletes suggest that there is a shoulder pain and overuse problem present in volleyball players, but minimal research has been done to establish rates and causes in juvenile participants. Purpose: To establish rates of shoulder pain, regardless of whether it resulted in a loss of playing time, in female high school volleyball players. A secondary goal was to determine whether high repetition volumes correlated with an increased likelihood of experiencing pain. Study Design: Descriptive epidemiology study. Methods: A self-report survey focusing on the prevalence of pain not associated with a traumatic event in female high school youth volleyball players was developed. Survey questions were formulated by certified athletic trainers, experienced volleyball coaches, and biomechanics experts. Surveys were received from 175 healthy, active high school volleyball players in Iowa, South Dakota, and Minnesota. Results: Forty percent (70/175) of active high school volleyball players remembered experiencing shoulder pain not related to traumatic injury, but only 33% (23/70) reported taking time off to recover from the pain. Based on these self-reported data, activities associated with significantly increased risk of nontraumatic shoulder pain included number of years playing competitive volleyball (P = .01) and lifting weights out of season (P = .001). Players who reported multiple risk factors were more likely to experience nontraumatic shoulder pain. Conclusion: When using time off for recovery as the primary injury criterion, we found that the incidence of shoulder pain is more than twice as high as the incidence of injury reported by previous studies. Findings also indicated that the incidence of shoulder pain

The prevention of baseball and softball injuries.

Science.gov (United States)

Janda, David H

2003-04-01

Forty million individuals participate in organized softball leagues each year in the United States. Eighteen million additional student athletes and young adults also participate in organized baseball league play. In addition to being two of the most popular team sports in the United States, they also are responsible for a significant percentage of sports-related injuries that are sustained in the United States. Fortunately, numerous interventions independently have been shown to be effective at reducing the injury scenario, which has grown to be of epidemic proportion. Interventions such as break-away bases, batting helmets, face shields on helmets, lighter mass baseballs, and teaching and reiteration of the fundamentals of softball and baseball all have been effective in preventing millions of injuries and billions of dollars in healthcare costs each year in the United States.

Study on Impact Loading and Humerus Injury for Baseball

Science.gov (United States)

Sakai, Shinobu; Oda, Juhachi; Yonemura, Shigeru; Sakamoto, Jiro

In the United States and Japan, baseball is a very popular sport played by many people. However, the ball used is hard and moves fast. A professional baseball pitcher in good form can throw a ball at speeds upwards of 41.7m/s (150km/hr). If a ball at this speed hits the batter, serious injury can occur. In this paper we will describe our investigations on the impact of a baseball with living tissues by finite element analysis. Baseballs were projected at a load cell plate using a specialized pitching machine. The dynamic properties of the baseball were determined by comparing the wall-ball collision experimentally measuring the time history of the force and the displacement using dynamic finite element analysis software (ANSYS/ LS-DYNA). The finite element model representing a human humerus and its surrounding tissue was simulated for balls pitched at variable speeds and pitch types (knuckle and fastball). In so doing, the stress distribution and stress wave in the bone and soft tissue were obtained. From the results, the peak stress of the bone nearly yielded to the stress caused by a high fast ball. If the collision position or direction is moved from the center of the upper arm, it is assumed that the stress exuded on the humerus will be reduced. Some methods to reduce the severity of the injury which can be applied in actual baseball games are also discussed.

Corked bats, juiced balls, and humidors: The physics of cheating in baseball

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Nathan, Alan M.; Smith, Lloyd V.; Faber, Warren L.; Russell, Daniel A.

2011-06-01

Three questions of relevance to Major League Baseball are investigated from a physics perspective. Can a baseball be hit farther with a corked bat? Is there evidence that the baseball is more lively today than in earlier years? Can storing baseballs in a temperature- or humidity-controlled environment significantly affect home run production? These questions are subjected to a physics analysis, including an experiment and an interpretation of the data. The answers to the three questions are no, no, and yes, respectively.

Concussion Education for High School Football Players: A Pilot Study

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Manasse-Cohick, Nancy J.; Shapley, Kathy L.

2014-01-01

This survey study compared high school football players' knowledge and attitudes about concussion before and after receiving concussion education. There were no significant changes in the Concussion Attitude Index. Results revealed a statistically significant difference in the athletes' scores for the Concussion Knowledge Index, "t"(244)…

Sport Nutrition Knowledge, Behaviors and Beliefs of High School Soccer Players

OpenAIRE

Manore, Melinda M.; Patton-Lopez, Megan M.; Meng, Yu; Wong, Siew Sun

2017-01-01

For adolescent athletes (14–18 years), data on sport nutrition knowledge, behaviors and beliefs are limited, especially based on sex, race/ethnicity and socioeconomic status. High school soccer players (n = 535; 55% female; 51% White, 41% Latino; 41% National School Lunch Program (NSLP) participants (80% Latino)) completed two questionnaires (demographic/health history and sport nutrition). The sport nutrition knowledge score was 45.6% with higher scores in NSLP-Whites vs. NSLP-Latinos (p <...

Medical management of youth baseball and softball tournaments.

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Kanaan, Matthew; Ray, Tracy R

2013-01-01

The medical management of youth baseball and softball tournaments requires both proper planning and a basic awareness of commonly seen sport-specific injuries. While youth sporting events are designed to be a fun experience for all, injuries and emergencies will occur. With proper planning, and supplies, the impact of these issues can be minimized. This article will outline some basic principles for the medical personnel that may be involved in youth baseball and softball events.

A training program to improve neuromuscular and performance indices in female high school basketball players.

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Noyes, Frank R; Barber-Westin, Sue D; Smith, Stephanie T; Campbell, Thomas; Garrison, Tiina T

2012-03-01

The purpose of this study was to determine if a sports-specific training program could improve neuromuscular and performance indices in female high school basketball players. We combined components from a published anterior cruciate ligament injury prevention program for jump and strength training with other exercises and drills to improve speed, agility, overall strength, and aerobic conditioning. We hypothesized that this sports-specific training program would lead to significant improvements in neuromuscular and performance indices in high school female basketball players. Fifty-seven female athletes aged 14-17 years participated in the supervised 6-week program, 3 d·wk(-1) for approximately 90-120 minutes per session. The program was conducted on the basketball court and in weight room facilities in high schools. The athletes underwent a video drop-jump test, multistage fitness test, vertical jump test, and an 18-m sprint test before and upon completion of the training program. All the subjects attended at least 14 training sessions. After training, a significant increase was found in the mean estimated VO2max (p basketball players.

Maxillofacial fractures sustained during baseball and softball.

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Yamamoto, Kazuhiko; Murakami, Kazuhiro; Sugiura, Tsutomu; Ishida, Jun-ichi; Imai, Yuichiro; Fujimoto, Masaki; Kirita, Tadaaki

2009-04-01

The purpose of this study was to investigate the demographics, the type of impact, the site and the treatment of maxillofacial fractures sustained during baseball and softball to develop an effective preventive strategy. Data of 82 patients treated for baseball- and softball-related maxillofacial fractures at the Department of Oral and Maxillofacial Surgery, Nara Medical University between 1982 and 2007 were retrospectively analyzed. Injuries were found in 64 men in baseball and 16 men and two women in softball with average ages of 19.6 and 30.0 years, respectively. Fractures were caused by being hit by the ball in 61 patients followed by collision in 16 patients. Fractures of the mandible and the mid-face were found in 44 and 38 patients, respectively. The mental and angle region of the mandible and zygoma and alveolar bone of the maxilla were frequently involved. Treatment was mostly conservative. Open reduction and internal fixation were performed only in 15 patients. Most maxillofacial fractures in these sports were ball-related. Therefore, effective preventive means should be considered to protect against such injuries.

Lower thoracic rib stress fractures in baseball pitchers.

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Gerrie, Brayden J; Harris, Joshua D; Lintner, David M; McCulloch, Patrick C

2016-01-01

Stress fractures of the first rib on the dominant throwing side are well-described in baseball pitchers; however, lower thoracic rib fractures are not commonly recognized. While common in other sports such as rowing, there is scant literature on these injuries in baseball. Intercostal muscle strains are commonly diagnosed in baseball pitchers and have a nearly identical presentation but also a highly variable healing time. The diagnosis of a rib stress fracture can predict a more protracted recovery. This case series presents two collegiate baseball pitchers on one team during the same season who were originally diagnosed with intercostal muscle strains, which following magnetic resonance imaging (MRI) were found to have actually sustained lower thoracic rib stress fractures. The first sustained a stress fracture of the posterior aspect of the right 8th rib on the dominant arm side, while the second presented with a left-sided 10th rib stress fracture on the nondominant arm side. In both cases, MRI was used to visualize the fractures as plain radiographs are insensitive and commonly negative early in patient presentation. Patients were treated with activity modification, and symptomatic management for 4-6 weeks with a graduated return to throwing and competition by 8-10 weeks. The repetitive high stresses incurred by pitching may cause either dominant or nondominant rib stress fractures and this should be included in the differential diagnosis of thoracic injuries in throwers. It is especially important that athletic trainers and team physicians consider this diagnosis, as rib fractures may have a protracted course and delayed return to play. Additionally, using the appropriate imaging techniques to establish an accurate diagnosis can help inform return-to-play decisions, which have important practical applications in baseball, such as roster management and eligibility.

COMPARISON OF MOTOR ABILITIES OF YOUTH FOOTBALL PLAYERS AND PRIMARY SCHOOL PUPILS

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Miroslav Smajić

2014-06-01

Full Text Available Introduction: Football as a complete sport that is rich in a wide variety of possible movements classified in polistructural, sports complex. To be a football player was able to perform tasks football has, among other things, and have the necessary level of motor abilities that can be achieved only through systematic implementation of training physical training. The aim of this research was to determine the differences in some of the motor abilities between the two researched groups. Methods: In a sample of 196 subjects average age of 12.45 ± 0.03 years, made a comparison of motor abilities. The first group consisted of 82 players - Pioneers FC "Red Star" from Belgrade and the other 114 primary school pupils from Novi Sad. A sample of 9 tests of motor abilities were: long jump from the place, running 20 m, 60 m running, bend straddle the gray, endurance in pull-ups, polygon backwards, slalom with three balls, hand tapping and lifting troops. Comparison of motor abilities of young players and pupils of primary schools was carried out by using multivariate analysis of variance (MANOVA. Results: An analysis of motor abilities between young players and primary school pupils were found statistically significant differences in all tested variables. Discussion: The research has shown that speed, endurance, coordination and muscle strength of the lower leg predominantly responsible for the success of matching the target foot at a distance, which is an integral part of the training process (Smajic and Molnar, 2007. It is also proven that there is a statistically significant correlation between the explosive and repetitive strength as a predictor of outcome-success rate for jumping in the air at youth players (Stankovic, 2011. References: Kuleš, B., Jerkovic, S. Maric, J. (1991. Influence of running different intentiteta to success in football. Kinesiology, 23 (1-2, 60-65. Malacko, J. (2000. Fundamentals of sports training - a quarter-supplemented and

Safety Tips: Baseball (For Parents)

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... and base runners and fielders frequently collide while running at top speed. Gear Guidelines As with all sports, wearing and using the right gear can go a long way toward preventing injuries. The amount of equipment required for baseball isn' ...

Inadequate Helmet Fit Increases Concussion Severity in American High School Football Players.

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Greenhill, Dustin A; Navo, Paul; Zhao, Huaqing; Torg, Joseph; Comstock, R Dawn; Boden, Barry P

2016-05-01

There is limited information on the relationship between football helmet fit and concussion severity. Poor helmet fit may predispose football players to a more severe concussion. Descriptive epidemiology study. Level 3. Data from concussion injury reports were obtained from the National High School Sports-Related Injury Surveillance System over a 9-year period. Symptoms, duration, and helmet parameters (fit, interior padding) were analyzed for all first-time concussions. Data from 4580 concussions were analyzed. Patients who suffered concussions with a helmet that did not fit properly (3.22%), as determined by an athletic trainer, had higher rates of drowsiness (RR, 1.46; P = 0.005), hyperexcitability (RR, 2.38; P = 0.047), and sensitivity to noise (RR, 1.88; P football helmet is a risk factor for a concussion with more symptoms and of longer duration. Concussions of longer duration are also more common in players with an air bladder-lined helmet. Current high school football rules should mandate supervision and maintenance of helmet fit throughout the season, prior to impact. Team physicians, athletic trainers, coaches, and high school officials should ensure proper oversight of helmet fit in high school athletes to decrease concussion severity and duration. © 2016 The Author(s).

Comparing the Immediate Effects of a Total Motion Release Warm-up and a Dynamic Warm-up Protocol on the Dominant Shoulder in Baseball Athletes.

Science.gov (United States)

Gamma, Stephen C; Baker, Russell; May, James; Seegmiller, Jeff G; Nasypany, Alan; Iorio, Steven M

2018-04-10

Gamma, SC, Baker, R, May, J, Seegmiller, JG, Nasypany, A, and Iorio, SM. Comparing the immediate effects of a total motion release warm-up and a dynamic warm-up protocol on the dominant shoulder in baseball athletes. J Strength Cond Res XX(X): 000-000, 2017-A decrease in total range of motion (ROM) of the dominant shoulder may predispose baseball athletes to increased shoulder injury risk; the most effective technique for improving ROM is unknown. The purpose of this study was to compare the immediate effects of Total Motion Release (TMR) to a generic dynamic warm-up program in baseball athletes. Baseball athletes (n = 20) were randomly assigned to an intervention group: TMR group (TMRG; n = 10) or traditional warm-up group (TWG; n = 10). Shoulder ROM measurements were recorded for internal rotation (IR) and external rotation (ER), the intervention was applied, and postmeasurements were recorded. Each group then received the other intervention and postmeasurements were again recorded. The time main effect (p ≤ 0.001) and the time × group interaction effect were significant (p ≤ 0.001) for IR and ER. Post hoc analysis revealed that TMR produced significant increases in mean IR (p ≤ 0.005, d = 1.52) and ER (p ≤ 0.018, d = 1.22) of the dominant shoulder initially. When groups crossed-over, the TMRG experienced a decrease in mean IR and ER after the dynamic warm-up, whereas the TWG experienced a significant increase in mean IR (p ≤ 0.001, d = 3.08) and ER (p ≤ 0.001, d = 2.56) after TMR intervention. Total Motion Release increased IR and ER of the dominant shoulder more than a dynamic warm-up. Dynamic warm-up after TMR also resulted in decreased IR and ER; however, TMR after dynamic warm-up significantly improved IR and ER. Based on these results, TMR is more effective than a generic dynamic warm-up for improving dominant shoulder ROM in baseball players.

Contribution of Visual Information about Ball Trajectory to Baseball Hitting Accuracy.

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Takatoshi Higuchi

Full Text Available The contribution of visual information about a pitched ball to the accuracy of baseball-bat contact may vary depending on the part of trajectory seen. The purpose of the present study was to examine the relationship between hitting accuracy and the segment of the trajectory of the flying ball that can be seen by the batter. Ten college baseball field players participated in the study. The systematic error and standardized variability of ball-bat contact on the bat coordinate system and pitcher-to-catcher direction when hitting a ball launched from a pitching machine were measured with or without visual occlusion and analyzed using analysis of variance. The visual occlusion timing included occlusion from 150 milliseconds (ms after the ball release (R+150, occlusion from 150 ms before the expected arrival of the launched ball at the home plate (A-150, and a condition with no occlusion (NO. Twelve trials in each condition were performed using two ball speeds (31.9 m·s-1 and 40.3 m·s-1. Visual occlusion did not affect the mean location of ball-bat contact in the bat's long axis, short axis, and pitcher-to-catcher directions. Although the magnitude of standardized variability was significantly smaller in the bat's short axis direction than in the bat's long axis and pitcher-to-catcher directions (p < 0.001, additional visible time from the R+150 condition to the A-150 and NO conditions resulted in a further decrease in standardized variability only in the bat's short axis direction (p < 0.05. The results suggested that there is directional specificity in the magnitude of standardized variability with different visible time. The present study also confirmed the limitation to visual information is the later part of the ball trajectory for improving hitting accuracy, which is likely due to visuo-motor delay.

The neurosurgeon as baseball fan and inventor: Walter Dandy and the batter's helmet.

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Brewster, Ryan; Bi, Wenya Linda; Smith, Timothy R; Gormley, William B; Dunn, Ian F; Laws, Edward R

2015-07-01

Baseball maintains one of the highest impact injury rates in all athletics. A principal causative factor is the "beanball," referring to a pitch thrown directly at a batter's head. Frequent morbidities elicited demand for the development of protective gear development in the 20th century. In this setting, Dr. Walter Dandy was commissioned to design a "protective cap" in 1941. His invention became widely adopted by professional baseball and inspired subsequent generations of batting helmets. As a baseball aficionado since his youth, Walter Dandy identified a natural partnership between baseball and medical practice for the reduction of beaning-related brain injuries. This history further supports the unique position of neurosurgeons to leverage clinical insights, inform innovation, and expand service to society.

Lower extremity kinematics and kinetics of Division III collegiate baseball and softball players while performing a modified pro-agility task.

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Wallace, B J; Kernozek, T W; Bothwell, E C

2007-12-01

Females experience at least twice as many non-contact anterior cruciate ligament (ACL) injuries as males. The aim of this study was to investigate if males and females exhibited different characteristics while performing a modified pro-agility test. Collegiate Division III male baseball (n=14) and female softball (n=13) players performed 4 trials of a modified pro-agility task, which consisted of running toward a force platform target for 5 steps, planting their right foot, and propelling themselves off of the target with their left foot. Kinematic and kinetic parameters were compared using a multivariate analysis of variance between gender with the level of significance set at P<0.05. Males and females exhibited similar knee valgus angles. Females had a greater maximum knee extension angle (10.14 degrees vs 17.43 degrees ), and greater knee range of motion (46.12 degrees vs 40.12 degrees ). Both groups reached maximum knee flexion at 52% of stance. Females had significantly more maximum hip flexion than males (28.86 degrees vs 22.75 degrees ). Females had significantly smaller minimum internal knee varus moments than their male counterparts (1.12 Nm/kg vs 1.55 Nm/kg). Vertical ground reaction forces as a percentage of bodyweight, and stance time, were not statistically different. The female group displayed an external knee rotation angle (2.49 degrees ) during the beginning of their stance, which was significantly different than the internal rotation angle (4.11 degrees ) in the male group. Early in stance knee rotation angle was highly correlated with the lack of internal knee varus moment (males R(2)=0.75, females R(2)=0.88). Females displayed knee moments and kinematics that may place them at greater risk for ACL injury during a stop-cut task. Females should be coached to perform stop cuts with more knee flexion and a more neutral knee rotation angle upon foot contact in an effort to reduce moments that may place the ACL at risk.

Oblique collisions of baseballs and softballs with a bat

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Kensrud, Jeffrey R.; Nathan, Alan M.; Smith, Lloyd V.

2017-07-01

Experiments are done by colliding a swinging bat with a stationary baseball or softball. Each collision was recorded with high-speed cameras from which the post-impact speed, launch angle, and spin of the ball could be determined. Initial bat speeds were in the range 63-88 mph, producing launch angles in the range 0°-30° and spins in the range 0-3,500 rpm. The results are analyzed in the context of a ball-bat collision model, and the parameters of that model are determined. For both baseballs and softballs, the data are consistent with a mechanism whereby the ball grips the surface of the bat, stretching the ball in the transverse direction and resulting in a spin that was up to 40% greater than would be obtained by rolling contact of rigid bodies. Using a lumped parameter contact model, baseballs are shown to be less compliant tangentially than softballs. Implications of our results for batted balls in game situations are presented.

Sport Nutrition Knowledge, Behaviors and Beliefs of High School Soccer Players.

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Manore, Melinda M; Patton-Lopez, Megan M; Meng, Yu; Wong, Siew Sun

2017-04-01

For adolescent athletes (14-18 years), data on sport nutrition knowledge, behaviors and beliefs are limited, especially based on sex, race/ethnicity and socioeconomic status. High school soccer players ( n = 535; 55% female; 51% White, 41% Latino; 41% National School Lunch Program (NSLP) participants (80% Latino)) completed two questionnaires (demographic/health history and sport nutrition). The sport nutrition knowledge score was 45.6% with higher scores in NSLP-Whites vs. NSLP-Latinos ( p nutritional requirements, but more than twice as likely to report that nutritional supplements were necessary for training ( p nutrition education that enhances food selection skills for health and sport performance.

Incidence of and risk factors for traumatic anterior shoulder dislocation: an epidemiologic study in high-school rugby players.

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Kawasaki, Takayuki; Ota, Chihiro; Urayama, Shingo; Maki, Nobukazu; Nagayama, Masataka; Kaketa, Takefumi; Takazawa, Yuji; Kaneko, Kazuo

2014-11-01

The incidence of reinjuries due to glenohumeral instability and the major risk factors for primary anterior shoulder dislocation in youth rugby players have been unclear. The purpose of this study was to investigate the incidence, mechanisms, and intrinsic risk factors of shoulder dislocation in elite high-school rugby union teams during the 2012 season. A total of 378 male rugby players from 7 high-school teams were investigated by use of self-administered preseason and postseason questionnaires. The prevalence of a history of shoulder dislocation was 14.8%, and there were 21 events of primary shoulder dislocation of the 74 overall shoulder injuries that were sustained during the season (3.2 events per 1000 player-hours of match exposure). During the season, 54.3% of the shoulders with at least one episode of shoulder dislocation had reinjury. This study also indicated that the persistence of glenohumeral instability might affect the player's self-assessed condition, regardless of the incidence during the current season. By a multivariate logistic regression method, a history of shoulder dislocation on the opposite side before the season was found to be a risk factor for contralateral primary shoulder dislocation (odds ratio, 3.56; 95% confidence interval, 1.27-9.97; P = .02). High-school rugby players with a history of shoulder dislocation are not playing at full capacity and also have a significant rate of reinjury as well as a high risk of dislocating the other shoulder. These findings may be helpful in deciding on the proper treatment of primary anterior shoulder dislocation in young rugby players. Copyright © 2014 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

MP3 Players: Applications and Implications for the Use of Popular Technology in Secondary Schools

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Stiler, Gary M.

2007-01-01

This article explores potential uses for MP3 players in secondary classrooms. It presents an overview of current applications and describes an exploratory study of classroom uses. Seven high school teachers and one teacher educator participated in a three-month project to examine MP3 technology as applied to high school instruction. Their ideas…

Prevalence of Os Styloideum in National Hockey League Players

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Greditzer, Harry G.; Hutchinson, Ian D.; Geannette, Christian S.; Hotchkiss, Robert N.; Kelly, Bryan T.; Potter, Hollis G.

2017-01-01

Background: Os styloideum describes an accessory carpal ossicle between the trapezoid, the capitate, and the second and third metacarpals. Injuries to this tissue have been described as part of the carpal boss syndrome. While the etiology of os styloideum remains uncertain, it may represent a physiologic response to altered loading forces in the wrist, similar to the development of cam-type deformity in the hips of ice hockey players or the Bennett lesion in the shoulders of baseball pitchers. Hypothesis: Professional hockey players will have a higher prevalence of os styloideum compared with the general population. Study Design: Case series. Level of Evidence: Level 4. Methods: A retrospective review of 16 professional hockey players from 4 different National Hockey League (NHL) teams who underwent unilateral imaging of the wrist was performed. Seventeen wrists were reviewed for the presence of os styloideum. Results: Thirteen of 16 players (81%) had an os styloideum, representing an increased prevalence compared with the general population. Previous clinical and cadaveric studies estimated a general prevalence of up to 19% (P < 0.001). For the 10 players who had their leading wrist scanned, 9 had an os styloideum (90%). Ten of 11 (91%) players demonstrated a bone marrow edema pattern within the metacarpal and the os styloideum on magnetic resonance imaging. There was no significant association between the presence of an os styloideum and the player’s position, leading wrist, or years in the league. Conclusion: There appears to be an increased prevalence of os styloideum among NHL players, and team physicians should consider this finding while formulating a differential diagnosis for dorsal wrist pain. Clinical Relevance: This study identified NHL players as having an increased prevalence of os styloideum compared with the general population. By doing so, these findings represent an opportunity to enhance our understanding of the etiology, clinical significance

Application of the matching law to pitch selection in professional baseball.

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Cox, David J; Sosine, Jacob; Dallery, Jesse

2017-04-01

This study applied the generalized matching equation (GME) to pitch selection in professional baseball. The GME was fitted to the relation between pitch selection and hitter outcomes for five professional baseball pitchers during the 2014 Major League Baseball season. The GME described pitch selection well. Pitch allocation varied across different game contexts such as inning, count, and number of outs in a manner consistent with the GME. Finally, within games, bias decreased for four of the five pitchers and the sensitivity parameter increased for three of the five pitchers. The results extend the generality of the GME to multialternative natural sporting contexts, and demonstrate the influence of context on behavior in natural environments. © 2017 Society for the Experimental Analysis of Behavior.

Effect of plyometric training on vertical jump height in high school basketball players: randomised control trial

OpenAIRE

Chhaya Verma, Lakshmi Subramanium, Vijaya Krishnan

2015-01-01

Background: Plyometric involve high intensity eccentric contraction immediately after a powerful concentric contraction. A vertical leap in basketball also involves rapid & repeated muscle contraction & stretching. Various methods have been used to improve the vertical leap in players, but only few studies mention about plyometrics. Aim: To determine the effect of Plyometric training on vertical jump height in high school basketball players & compare them with their untrained counterparts. Me...

High Prevalence of Nontraumatic Shoulder Pain in a Regional Sample of Female High School Volleyball Athletes

OpenAIRE

Frisch, Kayt E.; Clark, Jacob; Hanson, Chad; Fagerness, Chris; Conway, Adam; Hoogendoorn, Lindsay

2017-01-01

Background: Shoulder pain is becoming increasingly problematic in young players as volleyball gains popularity. Associations between repetitive motion and pain and overuse injury have been observed in other overhand sports (most notably baseball). Studies of adult athletes suggest that there is a shoulder pain and overuse problem present in volleyball players, but minimal research has been done to establish rates and causes in juvenile participants. Purpose: To establish rates of shoulder pai...

King-Devick Test reference values and associations with balance measures in high school American football players.

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Alsalaheen, B; Haines, J; Yorke, A; Diebold, J

2016-02-01

The King-Devick test appears to be a promising tool in screening for concussions. However, limited evidence exists on the baseline associations between the K-D test and age and baseline screening tools used after concussion. Additionally, there are no published reference values for the K-D test in high school football players. The K-D test, the Balance Error Scoring System, and the Limits of Stability (LOS) test were administered to 157 high school football players. Additionally, a subsample of 62 participants completed the test twice to examine the reliability of K-D test. There was no relationship between the K-D test and the BESS, or the reaction time and directional control of LOS test. Students aged between 16 and 18 years demonstrated faster K-D test performance compared to students between 13 and 15 years of age. However, there was no association between K-D test and history of concussion. The reliability of the K-D test was (ICC2,1 = 0.89), and the minimal detectable change was 6.10 s. Normative reference values for high school football players are presented in this study. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Real Time Baseball Database

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Fukue, Yasuhiro

The author describes the system outline, features and operations of "Nikkan Sports Realtime Basaball Database" which was developed and operated by Nikkan Sports Shimbun, K. K. The system enables to input numerical data of professional baseball games as they proceed simultaneously, and execute data updating at realtime, just-in-time. Other than serving as supporting tool for prepareing newspapers it is also available for broadcasting media, general users through NTT dial Q2 and others.

Saved at Home: Christian Branding and Faith Nights in the "Church of Baseball"

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Butterworth, Michael L.

2011-01-01

Baseball has enjoyed its status as the "national pastime" in part because it has been associated with democracy. To the extent that baseball, as an institution of civil religion, fosters pluralism and inclusion, it can indeed be viewed in democratic terms. In recent years, the advent of conservative Christian events called "Faith Nights" threatens…

Stress sonography of the ulnar collateral ligament of the elbow in professional baseball pitchers: a 10-year study.

Science.gov (United States)

Ciccotti, Michael G; Atanda, Alfred; Nazarian, Levon N; Dodson, Christopher C; Holmes, Laurens; Cohen, Steven B

2014-03-01

An injury to the ulnar collateral ligament (UCL) of the elbow is potentially career threatening for elite baseball pitchers. Stress ultrasound (US) of the elbow allows for evaluation of both the UCL and the ulnohumeral joint space at rest and with stress. Stress US can identify morphological and functional UCL changes and may predict the risk of a UCL injury in elite pitchers. Cross-sectional study; Level of evidence, 3. A total of 368 asymptomatic professional baseball pitchers underwent preseason stress US of their dominant and nondominant elbows over a 10-year period (2002-2012). Stress US examinations were performed in 30° of flexion at rest and with 150 N of valgus stress by a single musculoskeletal radiologist. Ligament thickness, ulnohumeral joint space width, and ligament abnormalities (hypoechoic foci and calcifications) were documented. There were 736 stress US studies. The mean UCL thickness in the dominant elbow (6.15 mm) was significantly greater than that in the nondominant elbow (4.82 mm) (P .05) increases in baseline ligament thickness, ulnohumeral joint space gapping with stress, and incidence of hypoechoic foci and calcifications. More than 1 stress US examination was performed in 131 players, with a mean increase of 0.78 mm in joint space gapping with subsequent evaluations. Stress US indicates that the UCL in the dominant elbow of elite pitchers is thicker, is more likely to have hypoechoic foci and/or calcifications, and has increased laxity with valgus stress over time.

Biomechanical Comparison of Three Perceived Effort Set Shots in Team Handball Players.

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Plummer, Hillary A; Gascon, Sarah S; Oliver, Gretchen D

2017-01-01

Plummer, HA, Gascon, SS, and Oliver, GD. Biomechanical comparison of three perceived effort set shots in team handball players. J Strength Cond Res 31(1): 80-87, 2017-Shoulder injuries are prevalent in the sport of team handball; however, no guidelines currently exist in the implementation of an interval throwing protocol for players returning from an upper extremity injury. These guidelines exist for the sport of baseball, but team handball may present additional challenges due to greater ball mass that must be accounted for. The purpose of this study was to examine kinematic differences in the team handball set shot at 50, 75, and 100% effort which are common throwing intensities in throwing protocols. Eleven male team handball players (23.09 ± 3.05 years; 185.12 ± 8.33 cm; 89.65 ± 12.17 kg) volunteered. An electromagnetic tracking system was used to collect kinematic data at the pelvis, trunk, scapula, and shoulder. Kinematic differences at the shoulder, trunk, and pelvis were observed across effort levels throughout the set shot with most occurring at ball release and maximum internal rotation. Significant differences in ball speed were observed between all 3 effort level shots (p handball players are able to gauge the effort at which they shoot; however, it cannot be assumed that these speeds will be at a certain percentage of their maximum. The results of this study provide valuable evidence that can be used to prepare a team handball player to return to throwing activities.

Inadequate Helmet Fit Increases Concussion Severity in American High School Football Players

Science.gov (United States)

Greenhill, Dustin A.; Navo, Paul; Zhao, Huaqing; Torg, Joseph; Comstock, R. Dawn; Boden, Barry P.

2016-01-01

Background: There is limited information on the relationship between football helmet fit and concussion severity. Hypothesis: Poor helmet fit may predispose football players to a more severe concussion. Study Design: Descriptive epidemiology study. Level of Evidence: Level 3. Methods: Data from concussion injury reports were obtained from the National High School Sports-Related Injury Surveillance System over a 9-year period. Symptoms, duration, and helmet parameters (fit, interior padding) were analyzed for all first-time concussions. Results: Data from 4580 concussions were analyzed. Patients who suffered concussions with a helmet that did not fit properly (3.22%), as determined by an athletic trainer, had higher rates of drowsiness (RR, 1.46; P = 0.005), hyperexcitability (RR, 2.38; P = 0.047), and sensitivity to noise (RR, 1.88; P < 0.001); had more symptoms (5.34 vs 4.54, P = 0.004); and had longer symptom duration (P = 0.04). Athletes with helmets lined with an air bladder had greater rates of sensitivity to light (RR, 1.13; P = 0.02), sensitivity to noise (RR, 1.25; P = 0.009), and longer symptom duration (P = 0.004) compared with foam or gel liners. Conclusion: An improperly fitted football helmet is a risk factor for a concussion with more symptoms and of longer duration. Concussions of longer duration are also more common in players with an air bladder–lined helmet. Current high school football rules should mandate supervision and maintenance of helmet fit throughout the season, prior to impact. Clinical Relevance: Team physicians, athletic trainers, coaches, and high school officials should ensure proper oversight of helmet fit in high school athletes to decrease concussion severity and duration. PMID:27005467

Baseball fans don't like lumpy batters: Influence of domain knowledge on the access of subordinate meanings.

Science.gov (United States)

Wiley, Jennifer; George, Tim; Rayner, Keith

2016-11-08

Two experiments investigated the effects of domain knowledge on the resolution of ambiguous words with dominant meanings related to baseball. When placed in a sentence context that strongly biased toward the non-baseball meaning (positive evidence), or excluded the baseball meaning (negative evidence), baseball experts had more difficulty than non-experts resolving the ambiguity. Sentence contexts containing positive evidence supported earlier resolution than did the negative evidence condition for both experts and non-experts. These experiments extend prior findings, and can be seen as support for the reordered access model of lexical access, where both prior knowledge and discourse context influence the availability of word meanings.

Epidemiology of Knee Sprains in Youth, High School, and Collegiate American Football Players.

Science.gov (United States)

Clifton, Daniel R; Onate, James A; Schussler, Eric; Djoko, Aristarque; Dompier, Thomas P; Kerr, Zachary Y

2017-05-01

  Variations in knee-sprain incidence among competition levels are unclear but may help inform prevention strategies in American football players.   To describe the epidemiology of knee sprains in youth, high school, and collegiate football players.   Descriptive epidemiology study.   Injury and athlete-exposure (AE) data were collected from 3 injury-surveillance programs at the youth, high school, and collegiate competition levels.   Data from 310 youth, 184 high school, and 71 collegiate football team-seasons were collected during the 2012 through 2014 seasons.   Knee-sprain rates and risks were calculated for each competition level. Injury rate ratios (IRRs) and risk ratios (RRs) compared knee-sprain rates by competition level. Injury proportion ratios (IPRs) compared differences in surgery needs, recurrence, injury mechanism, and injury activity by competition level.   Knee-sprain rates in youth, high school, and collegiate football were 0.16/1000 AEs, 0.25/1000 AEs, and 0.69/1000 AEs, respectively. Knee-sprain rates increased as the competition level increased (high school versus youth: IRR = 1.60; 95% confidence interval [CI] = 1.12, 2.30; collegiate versus high school: IRR = 2.73; 95% CI = 2.38, 3.96). Knee-sprain risk was highest in collegiate (4.3%), followed by high school (2.0%) and youth (0.5%) athletes. Knee-sprain risk increased as the competition level increased (high school versus youth: RR = 3.73; 95% CI = 2.60, 5.34; collegiate versus high school: RR = 2.14; 95% CI = 1.83, 2.51). Collegiate football had the lowest proportion of knee sprains that were noncontact injuries (collegiate versus youth: IPR = 0.54; 95% CI = 0.31, 0.95; collegiate versus high school: IPR = 0.59; 95% CI = 0.44, 0.79) and the lowest proportion that occurred while being tackled (collegiate versus youth: IPR = 0.44; 95% CI = 0.26, 0.76; collegiate versus high school: IPR = 0.71; 95% CI = 0.51, 0.98).   Knee-sprain incidence was highest in collegiate football

The Effects of Verbal Instruction and Shaping to Improve Tackling by High School Football Players

Science.gov (United States)

Harrison, Antonio M.; Pyles, David A.

2013-01-01

We evaluated verbal instruction and shaping using TAG (teaching with acoustical guidance) to improve tackling by 3 high school football players. Verbal instruction and shaping improved tackling for all 3 participants. In addition, performance was maintained as participants moved more quickly through the tackling procedure.

Multiple Past Concussions in High School Football Players: Are There Differences in Cognitive Functioning and Symptom Reporting?

Science.gov (United States)

Brooks, Brian L; Mannix, Rebekah; Maxwell, Bruce; Zafonte, Ross; Berkner, Paul D; Iverson, Grant L

2016-12-01

There is increasing concern about the possible long-term effects of multiple concussions, particularly on the developing adolescent brain. Whether the effect of multiple concussions is detectable in high school football players has not been well studied, although the public health implications are great in this population. To determine if there are measureable differences in cognitive functioning or symptom reporting in high school football players with a history of multiple concussions. Cross-sectional study; Level of evidence, 3. Participants included 5232 male adolescent football players (mean [±SD] age, 15.5 ± 1.2 years) who completed baseline testing between 2009 and 2014. On the basis of injury history, athletes were grouped into 0 (n = 4183), 1 (n = 733), 2 (n = 216), 3 (n = 67), or ≥4 (n = 33) prior concussions. Cognitive functioning was measured by the Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) battery, and symptom ratings were obtained from the Post-Concussion Symptom Scale. There were no statistically significant differences between groups (based on the number of reported concussions) regarding cognitive functioning. Athletes with ≥3 prior concussions reported more symptoms than did athletes with 0 or 1 prior injury. In multivariate analyses, concussion history was independently related to symptom reporting but less so than developmental problems (eg, attention or learning problems) or other health problems (eg, past treatment for psychiatric problems, headaches, or migraines). In the largest study to date, high school football players with multiple past concussions performed the same on cognitive testing as those with no prior concussions. Concussion history was one of several factors that were independently related to symptom reporting. © 2016 The Author(s).

Beyond the Playing Field: Jackie Robinson, Civil Rights Advocate. Lesson Plan.

Science.gov (United States)

National Archives and Records Administration, Washington, DC.

This packet provides primary source documents and lesson plans relating to the study of Jackie Robinson as a civil rights advocate. The legendary baseball player, Jack Roosevelt Robinson, was the first black man to "officially" play in the big leagues in the 20th century. Jackie Robinson was not only a stellar baseball player, but he…

Pearl Harbor: A Failure for Baseball?

Science.gov (United States)

Crepeau, Richard C.

The history of sports is closely tied to the larger history of the society in which they are played. Baseball in the United States in the 1920's and l930's assumed a major role in spreading the ideals of fair play, sportsmanship, and democracy to the Far East, with tours by amateur athletes and professionals such as Lou Gehrig and Babe Ruth. Even…

Haglund's Deformity

Science.gov (United States)

... years before seeking treatment.What Is a... Baseball Injuries to the Foot and Ankle Your feet and ankles take a beating when you’re playing baseball. Baseball players should be aware of the following risks. Ankle sprains may occur while running, fielding balls... In Women's Shoes, Pain Does Not ...

Peroneal Tendon Injuries

Science.gov (United States)

... Where do you hurt? Interactive Foot Diagram Baseball Injuries to the Foot and Ankle Your feet and ankles take a beating when you’re playing baseball. Baseball players should be aware of the following risks. Ankle sprains may occur while running, fielding balls... Ankle Pain Ankle pain is often ...

Balance improvements in female high school basketball players after a 6-week neuromuscular-training program.

Science.gov (United States)

McLeod, Tamara C Valovich; Armstrong, Travis; Miller, Mathew; Sauers, Jamie L

2009-11-01

Poor balance has been associated with increased injury risk among athletes. Neuromuscular-training programs have been advocated as a means of injury prevention, but little is known about the benefits of these programs on balance in high school athletes. To determine whether there are balance gains after participation in a neuromuscular-training program in high school athletes. Nonrandomized controlled trial. All data were collected at each participating high school before and after a 6-wk intervention or control period. 62 female high school basketball players recruited from the local high school community and assigned to a training (n = 37) or control (n = 25) group. Training-group subjects participated in a 6-wk neuromuscular-training program that included plyometric, functional-strengthening, balance, and stability-ball exercises. Data were collected for the Balance Error Scoring System (BESS) and Star Excursion Balance Test (SEBT) before and after the 6-wk intervention or control period. The authors found a significant decrease in total BESS errors in the trained group at the posttest compared with their pretest and the control group (P = .003). Trained subjects also scored significantly fewer BESS errors on the single-foam and tandem-foam conditions at the posttest than the control group and demonstrated improvements on the single-foam compared with their pretest (P = .033). The authors found improvements in reach in the lateral, anteromedial, medial, and posterior directions in the trained group at the posttest compared with the control group (P training program can increase the balance and proprioceptive capabilities of female high school basketball players and that clinical balance measures are sensitive to detect these differences.

Balance Regularity Among Former High School Football Players With or Without a History of Concussion.

Science.gov (United States)

Schmidt, Julianne D; Terry, Douglas P; Ko, Jihyun; Newell, Karl M; Miller, L Stephen

2018-02-01

  Subclinical postural-control changes may persist beyond the point when athletes are considered clinically recovered postconcussion.   To compare postural-control performance between former high school football players with or without a history of concussion using linear and nonlinear metrics.   Case-control study.   Clinical research laboratory.   A total of 11 former high school football players (age range, 45-60 years) with 2 or more concussions and 11 age- and height-matched former high school football players without a history of concussion. No participant had college or professional football experience.   Participants completed the Sensory Organization Test. We compared postural control (linear: equilibrium scores; nonlinear: sample and multiscale entropy) between groups using a 2 × 3 analysis of variance across conditions 4 to 6 (4: eyes open, sway-referenced platform; 5: eyes closed, sway-referenced platform; 6: eyes open, sway-referenced surround and platform).   We observed a group-by-condition interaction effect for medial-lateral sample entropy ( F 2,40 = 3.26, P = .049, η p 2 = 0.140). Participants with a history of concussion presented with more regular medial-lateral sample entropy values (0.90 ± 0.41) for condition 5 than participants without a history of concussion (1.30 ± 0.35; mean difference = -0.40; 95% confidence interval [CI] = -0.74, -0.06; t 20 = -2.48, P = .02), but conditions 4 (mean difference = -0.11; 95% CI: -0.37, 0.15; t 20 = -0.86, P = .40) and 6 (mean difference = -0.25; 95% CI: -0.55, 0.06; t 20 = -1.66, P = .11) did not differ between groups.   Postconcussion deficits, detected using nonlinear metrics, may persist long after injury resolution. Subclinical concussion deficits may persist for years beyond clinical concussion recovery.

Shoulder joint velocity during fastball pitching in baseball

NARCIS (Netherlands)

Gasparutto, X.; van der Graaff, E; van der Helm, F.C.T.; Veeger, H.E.J.; Colloud, F.; Domalain, M.; Monnet, T.

2015-01-01

The purpose of this study was to assess the rotation and translation velocity of the shoulder complex during fastball pitching in baseball. 8 pitchers from the Dutch AAA team performed each 3 fastball pitches. Their motion was recorded by an opto-electronic device. Kinematic computation was

Relative age and birthplace effect in Japanese professional sports: a quantitative evaluation using a Bayesian hierarchical Poisson model.

Science.gov (United States)

Ishigami, Hideaki

2016-01-01

Relative age effect (RAE) in sports has been well documented. Recent studies investigate the effect of birthplace in addition to the RAE. The first objective of this study was to show the magnitude of the RAE in two major professional sports in Japan, baseball and soccer. Second, we examined the birthplace effect and compared its magnitude with that of the RAE. The effect sizes were estimated using a Bayesian hierarchical Poisson model with the number of players as dependent variable. The RAEs were 9.0% and 7.7% per month for soccer and baseball, respectively. These estimates imply that children born in the first month of a school year have about three times greater chance of becoming a professional player than those born in the last month of the year. Over half of the difference in likelihoods of becoming a professional player between birthplaces was accounted for by weather conditions, with the likelihood decreasing by 1% per snow day. An effect of population size was not detected in the data. By investigating different samples, we demonstrated that using quarterly data leads to underestimation and that the age range of sampled athletes should be set carefully.

Kinematics of Shooting in High School and Collegiate Lacrosse Players With and Without Low Back Pain.

Science.gov (United States)

Wasser, Joseph G; Chen, Cong; Vincent, Heather K

2016-07-01

Low back pain (LBP) and motion alterations can occur in athletes who engage in high-speed throwing motions. The relationship between LBP and shooting motion in lacrosse players is not yet known. To quantify the effects of LBP on key kinematic parameters of the lacrosse shot and determine the contribution of the severity of LBP on specific kinematic parameters of the shooting motion. Controlled laboratory study. High school and collegiate players (N = 24) were stratified into 2 groups based on back pain symptoms (LBP or no pain). Three-dimensional motion capture of overhead throws was used to collect data on knee, pelvis, trunk, and shoulder kinematics as well as crosse stick (the stick capped with a strung net) and ball speed. Mean low back numeric pain rating scale (NRSpain) score was 2.9. Knee flexion at ball release was greater in the LBP than no pain group, indicating a more bent knee (P = .04). The LBP group demonstrated less angular velocity transfer from pelvis to trunk than the no pain group (P = .05). Total range of motion of the pelvis and shoulders during the shot and follow-through were less in the LBP group than the no pain group (83.6° ± 24.5° vs 75.9° ± 24.5°, P = .05). Age- and sex-adjusted regression analyses revealed that the low back NRSpain rating contributed 6.3% to 25.0% of the variance to the models of shoulder transverse rotation range of motion, trunk and shoulder rotation angular velocities, and knee flexion angle (P core training and prehabilitation programs for high school and collegiate players may reduce pain in affected players as well as help them to attain appropriate motion parameters and avoid secondary musculoskeletal injuries. This research identified a prehabilitation need in the understudied lacrosse population. Therapeutic strategies can be developed to strengthen the throwing motion, which could control mechanical loading patterns on the low back and minimize pain symptoms in players with chronic LBP.

Curve ball baseball, statistics, and the role of chance in the game

CERN Document Server

Bennett, Jay

2001-01-01

In its formative years, from the 1970s through the 1990s, sabermetrics was p- marily an amateur undertaking. Publications were aimed at a relatively small audience of baseball fans. To be sure, this ever-growing group of aficionados brought a lot of sophistication to baseball analysis, and were constantly looking for statistical insights beyond the listings of the top ten batters found in popular newspapers and magazines. But their influence on the baseball profession was very limited. A few consultants like Craig Wright developed temporary relati- ships with various teams, but none were able to stay long enough to create a p- manent sabermetrician staff position. (See Rob Neyer’s November 11, 2002, arti- 1 cle on ESPN. com. ) All of this changed, however, in 2002 with the hiring of Bill James by the Boston Red Sox. With that move, we have seen the admittance of the foremost proponent of sabermetrics into the top echelon of professional ba- ball management. The art and science of careful statistical analysi...

A Prospective Epidemiological Study of Injuries in Japanese National Tournament-Level Badminton Players From Junior High School to University.

Science.gov (United States)

Miyake, Eiji; Yatsunami, Mitsunobu; Kurabayashi, Jun; Teruya, Koji; Sekine, Yasuhiro; Endo, Tatsuaki; Nishida, Ryuichiro; Takano, Nao; Sato, Seiko; Jae Kyung, Han

2016-03-01

Injury prevention programs have recently been created for various sports. However, a longitudinal study on badminton injuries, as assessed by a team's dedicated medical staff, at the gymnasium has not been performed. We aimed to perform the first such study to measure the injury incidence, severity and type as the first step in creating a badminton injury prevention program. A prospective, longitudinal survey was conducted between April 2012 and March 2013 with 133 national tournament-level badminton players from junior high school to university in Japan with the teams' physical therapists at the gymnasium. Injury incidence was measured as the injury rate (IR) for every 1,000 hour (1000 hour) and IR for every 1,000 athlete exposures (1000 AE). Severity was classified in 5 levels by the number of days the athlete was absent from practice or matches. Injury types were categorized as trauma or overuse. Practice (IR) (1,000 hour) was significantly higher in female players than in male players; the rates increased with increasing age. IR (1,000 AE) was significantly higher in matches than in practice in both sexes of all ages, except for female junior high school students and injuries were most frequent for high school students in matches. The majority of the injuries were slight (83.8%); overuse injuries occurred approximately 3 times more than trauma. This is the first study in which medical staff assessed injuries in badminton, providing value through benchmark data. Injury prevention programs are particularly necessary for female university students in practice and high school students in matches.

Deficits in glenohumeral passive range of motion increase risk of elbow injury in professional baseball pitchers: a prospective study.

Science.gov (United States)

Wilk, Kevin E; Macrina, Leonard C; Fleisig, Glenn S; Aune, Kyle T; Porterfield, Ron A; Harker, Paul; Evans, Timothy J; Andrews, James R

2014-09-01

Injuries to the elbow joint in baseball pitchers appear common. There appears to be a correlation between shoulder range of motion and elbow injuries. To prospectively determine whether decreased ROM of the throwing shoulder is correlated with the onset of elbow injuries in professional baseball pitchers. Cohort study; Level of evidence, 2. For 8 consecutive years (2005-2012), passive range of motion of both the throwing and nonthrowing shoulders of all major and minor league pitchers within a single professional baseball organization were measured by using a bubble goniometer during spring training. In total, 505 examinations were conducted on 296 pitchers. Glenohumeral external rotation and internal rotation were assessed in the supine position with the arm at 90° of abduction and in the plane of the scapula. The scapula was stabilized per methods previously established. Total rotation was defined as the sum of external rotation and internal rotation. Passive shoulder flexion was assessed with the subject supine and the scapula stabilized per methods previously established. Elbow injuries and days missed because of elbow injuries were assessed and recorded by the medical staff of the team. Throwing and nonthrowing shoulder measurements were compared by using Student t tests; 1-tailed Fisher exact tests were performed to identify significant associations between shoulder motion and elbow injury. Nominal logistic regression was performed to determine the odds of elbow injury. Significant differences were noted during side-to-side comparisons within subjects. There were 49 elbow injuries and 8 surgeries in 38 players, accounting for a total of 2551 days missed. Neither glenohumeral internal rotation deficit nor external rotation insufficiency was correlated with elbow injuries. Pitchers with deficits of >5° in total rotation in their throwing shoulders had a 2.6 times greater risk for injury. Pitchers with deficit of ≥5° in flexion of the throwing shoulder had

Evaluation of the King-Devick test as a concussion screening tool in high school football players.

Science.gov (United States)

Seidman, Daniel H; Burlingame, Jennifer; Yousif, Lina R; Donahue, Xinh P; Krier, Joshua; Rayes, Lydia J; Young, Rachel; Lilla, Muareen; Mazurek, Rochelle; Hittle, Kristie; McCloskey, Charles; Misra, Saroj; Shaw, Michael K

2015-09-15

Concussion is the most common type of traumatic brain injury, and results from impact or impulsive forces to the head, neck or face. Due to the variability and subtlety of symptoms, concussions may go unrecognized or be ignored, especially with the pressure placed on athletes to return to competition. The King-Devick (KD) test, an oculomotor test originally designed for reading evaluation, was recently validated as a concussion screening tool in collegiate athletes. A prospective study was performed using high school football players in an attempt to study the KD as a concussion screening tool in this younger population. 343 athletes from four local high school football teams were recruited to participate. These athletes were given baseline KD tests prior to competition. Individual demographic information was collected on the subjects. Standard team protocol was employed to determine if a concussion had occurred during competition. Immediately after diagnosis, the KD test was re-administered to the concussed athlete for comparison to baseline. Post-season testing was also performed in non-concussed individuals. Of the 343 athletes, nine were diagnosed with concussions. In all concussed players, cumulative read times for the KD test were significantly increased (phistory of concussion was the only demographic factor predictive of concussion in this cohort. The KD test is an accurate and easily administered sideline screening tool for concussion in adolescent football players. Copyright © 2015 Elsevier B.V. All rights reserved.

Anthropometric and Athletic Performance Combine Test Results Among Positions Within Grade Levels of High School-Aged American Football Players.

Science.gov (United States)

Leutzinger, Todd J; Gillen, Zachary M; Miramonti, Amelia M; McKay, Brianna D; Mendez, Alegra I; Cramer, Joel T

2018-05-01

Leutzinger, TJ, Gillen, ZM, Miramonti, AM, McKay, BD, Mendez, AI, and Cramer, JT. Anthropometric and athletic performance combine test results among positions within grade levels of high school-aged American football players. J Strength Cond Res 32(5): 1288-1296, 2018-The purpose of this study was to investigate differences among player positions at 3 grade levels in elite, collegiate-prospective American football players. Participants' data (n = 7,160) were analyzed for this study (mean height [Ht] ± SD = 178 ± 7 cm, mass [Bm] = 86 ± 19 kg). Data were obtained from 12 different high school American football recruiting combines hosted by Zybek Sports (Boulder, Colorado). Eight 2-way (9 × 3) mixed factorial analysis of variances {position (defensive back [DB], defensive end, defensive lineman, linebacker, offensive lineman [OL], quarterback, running back, tight end, and wide receiver [WR]) × grade (freshmen, sophomores, and juniors)} were used to test for differences among the mean test scores for each combine measure (Ht, Bm, 40-yard [40 yd] dash, proagility [PA] drill, L-cone [LC] drill, vertical jump [VJ], and broad jump [BJ]). There were position-related differences (p ≤ 0.05) for Ht, 40 yd dash, and BJ, within each grade level and for Bm, PA, LC, and VJ independent of grade level. Generally, the results showed that OL were the tallest, weighed the most, and exhibited the lowest performance scores among positions. Running backs were the shortest, whereas DBs and WRs weighed the least and exhibited the highest performance scores among positions. These results demonstrate the value of classifying high school-aged American football players according to their specific position rather than categorical groupings such as "line" vs. "skill" vs. "big skill" when evaluating anthropometric and athletic performance combine test results.

Pilot study of female high school basketball players' anterior cruciate ligament injury knowledge, attitudes, and practices.

Science.gov (United States)

Iversen, M D; Friden, C

2009-08-01

An anterior cruciate ligament (ACL) injury prevention program was evaluated. One hundred and thirteen female high school varsity and junior varsity basketball players and 12 coaches participated in an 8-week educational and skills program. Demographic and injury history data were collected. At pre-intervention and at the end of season, knowledge, attitudes, and practices about ACL risk and injury prevention were assessed via questionnaires, and frequency of two-footed landings were videotaped during games. Univariate statistics described the sample. Paired t-tests evaluated the program's impact. Cronbach's alpha, correlations, and kappa statistics assessed the validity and reliability of questionnaires and video analysis. Of the 113 players, 74 completed the study. The players' mean age was 16.25 years (SD=1.07; range=14.2-18.8). Baseline knowledge score was 57.2%, practice 58.4%, and attitude 73.5%. The mean baseline knowledge score of the 12 coaches (mean age=40.8 years; SD=10.3; range=26.9-56.3) was 68.7%. Players' knowledge about ACL injury prevention improved (t=2.57; P<0.01). No changes in attitudes toward injury prevention were found (t(diff)=1.88; P<0.06). Inter-rater reliability of two-footed landings observed was acceptable (kappa=0.72). Videotape analyses revealed a 5.5% increase in landing performance (t(diff)=9.6; P<0.0001). The program increased knowledge about ACL injury risk and improved player's landing skills.

The Jackie Robinson I Remember.

Science.gov (United States)

Kahn, Roger

1997-01-01

This memoir describes Jackie Robinson's historic career as the first black player in major league baseball, emphasizing his courage and determination in the face of racism, and recounting the background to his entry into baseball. (SLD)

Leadership styles of elite Dixie youth baseball coaches.

Science.gov (United States)

Bennett, G; Maneval, M

1998-12-01

Chelladurai and Saleh's Leadership Scale for Sports was administered to 52 elite Dixie Youth baseball coaches. Analyses indicated that subjects scored high in positive feedback, training and instruction, and social support, moderate in democratic behavior, and low in autocratic behavior. These results seem to support the validity of using the scale to compare coaching behavior.

A COMPARATIVE STUDY RELATING PASS BETWEEN MALE AND FEMALE BASKETBALL PLAYERS

Directory of Open Access Journals (Sweden)

Antonios THEOHAROPOULOS

2010-04-01

Full Text Available The main goal of this research is to examine the importance of different kind of passes through their frequency of appearance and success that male and female basketball players execute in Greek championships.The sample consisted of male and female teams of Thessaloniki - Greece. The 1st group consisted of male teams (18 from different divisions while the 2nd group consisted of female teams (10. Data collection was based on personal observation by a research team, who registries the kind of passes that took place either from the sampleteam or the opposite teams. The passes that were registered are: behind the back, chest, overhead, push, hand with hand, bounce and baseball pass. The analysis of variance (Anova in types of passes was formed, based on the factor “sex” (male-female. Specifically the comparisons were made between: a the total number of eachpass b their successful number c their frequency of appearance d and their total successful percentage. The results indicate that statistically significant differences exist between the two sexes, concerning the total number, the successful number and the percentages of success for the most used passes in Greek basketball. The analysis indicates that male and female basketball players tend to use different kind of passes during activity.

Baseball II-T, a new target plasma startup experiment

International Nuclear Information System (INIS)

Chargin, A.; Denhoy, B.; Frank, A.; Thomas, S.

1975-01-01

A brief description is given of modifications and additions to the existing Baseball II experiment. These changes will make it possible to study target plasma buildup in a steady-state magnetic field. This experiment, now called Baseball II-T + will use a pellet generator to deliver ammonia pellets into the center of the magnetic mirror field where they will be heated with a 300-J, 50-ns, CO 2 laser. The plasma created by this method will have a density of approximately 10 13 cm -3 and a temperature of about 1 keV. This target plasma will be used for neutral beam injection startup studies with a 50-A, 20-keV neutral beam. Later, the beam power will be increased to study buildup. With ion injection energies of up to 50 keV, it may be possible to achieve etatau as high as 10 12 cm -3 s. The new components necessary to achieve these goals are described

Comparison of Indiana High School Football Injury Rates by Inclusion of the USA Football "Heads Up Football" Player Safety Coach.

Science.gov (United States)

Kerr, Zachary Y; Dalton, Sara L; Roos, Karen G; Djoko, Aristarque; Phelps, Jennifer; Dompier, Thomas P

2016-05-01

In Indiana, high school football coaches are required to complete a coaching education course with material related to concussion awareness, equipment fitting, heat emergency preparedness, and proper technique. Some high schools have also opted to implement a player safety coach (PSC). The PSC, an integral component of USA Football's Heads Up Football (HUF) program, is a coach whose primary responsibility is to ensure that other coaches are implementing proper tackling and blocking techniques alongside other components of the HUF program. To compare injury rates in Indiana high school football teams by their usage of a PSC or online coaching education only. Cohort study; Level of evidence, 2. Athletic trainers (ATs) evaluated and tracked injuries at each practice and game during the 2015 high school football season. Players were drawn from 6 teams in Indiana. The PSC group, which used the PSC component, was comprised of 204 players from 3 teams. The "education only" group (EDU), which utilized coaching education only, was composed of 186 players from 3 teams. Injury rates and injury rate ratios (IRRs) were reported with 95% confidence intervals (CIs). During 25,938 athlete-exposures (AEs), a total of 149 injuries were reported, of which 54 (36.2%) and 95 (63.8%) originated from the PSC and EDU groups, respectively. The practice injury rate was lower in the PSC group than the EDU group (2.99 vs 4.83/1000 AEs; IRR, 0.62; 95% CI, 0.40-0.95). The game injury rate was also lower in the PSC group than the EDU group (11.37 vs 26.37/1000 AEs; IRR, 0.43; 95% CI, 0.25-0.74). When restricted to concussions only, the rate was lower in the PSC group (0.09 vs 0.73/1000 AEs; IRR, 0.12; 95% CI, 0.01-0.94), although only 1 concussion was reported in the PSC group. No differences were found in game concussion rates (0.60 vs 4.39/1000 AEs; IRR, 0.14; 95% CI, 0.02-1.11). Findings support the PSC as an effective method of injury mitigation in high school football. Future research

The Use of Ice in Baseball Injuries (Cryotherapy).

Science.gov (United States)

Suspenski, Thomas J.

Cryotherapy (the use of ice and exercise to rehabilitate athletic injuries) can be an effective method of treating baseball injuries. It is generally agreed that ice is appropriate for the first 24 to 48 hours, but there is disagreement over its use beyond 72 hours. Some physicians and trainers support the use of heat with either exercise or rest,…

Major League Baseball Anti-Trust Immunity: Examining the Legal and Financial Implications of Relocation Rules

OpenAIRE

Mark, Nagel; Matt, Brown; Daniel, Rascher; Chad, McEvoy

2006-01-01

Major League Baseball (MLB) rules restrict the movement of any franchise into another’s territory. These territorial rules are designed to protect each team’s potential local revenue sources as well as to provide stability throughout the league. Recently, Major League Baseball approved financial compensation for the Washington Nationals’ move into the Baltimore Orioles’ territory – primarily because it was in the best interest of MLB even though it hurt the Orioles. However, the Oakland Athle...

Simulation in Sport Finance

OpenAIRE

Joris, Drayer; Daniel, Rascher

2010-01-01

Simulations have long been used in business schools to give students experience making real-world decisions in a relatively low-risk environment. The OAKLAND A’S BASEBALL BUSINESS SIMULATOR takes a traditional business simulation and applies it to the sport industry where sales of tangible products are replaced by sales of an experience provided to fans. The simulator asks students to make decisions about prices for concessions, parking, and merchandise, player payroll expenses, funding for...

Kinematic and Kinetic Profiles of Trunk and Lower Limbs during Baseball Pitching in Collegiate Pitchers

Directory of Open Access Journals (Sweden)

Masahiro Kageyama, Takashi Sugiyama, Yohei Takai, Hiroaki Kanehisa, Akira Maeda

2014-12-01

Full Text Available The purpose of this study was to clarify differences in the kinematic and kinetic profiles of the trunk and lower extremities during baseball pitching in collegiate baseball pitchers, in relation to differences in the pitched ball velocity. The subjects were 30 collegiate baseball pitchers aged 18 to 22 yrs, who were assigned to high- (HG, 37.4 ± 0.8 m·s-1 and low-pitched-ball-velocity groups (LG, 33.3 ± 0.8 m·s-1. Three-dimensional motion analysis with a comprehensive lower-extremity model was used to evaluate kinematic and kinetic parameters during baseball pitching. The ground-reaction forces (GRF of the pivot and stride legs during pitching were determined using two multicomponent force plates. The joint torques of hip, knee, and ankle were calculated using inverse-dynamics computation of a musculoskeletal human model. To eliminate any effect of variation in body size, kinetic and GRF data were normalized by dividing them by body mass. The maxima and minima of GRF (Fy, Fz, and resultant forces on the pivot and stride leg were significantly greater in the HG than in the LG (p < 0.05. Furthermore, Fy, Fz, and resultant forces on the stride leg at maximum shoulder external rotation and ball release were significantly greater in the HG than in the LG (p < 0.05. The hip abduction, hip internal rotation and knee extension torques of the pivot leg and the hip adduction torque of the stride leg when it contacted the ground were significantly greater in the HG than in the LG (p < 0.05. These results indicate that, compared with low-ball-velocity pitchers, high-ball-velocity pitchers can generate greater momentum of the lower limbs during baseball pitching.

Are the hamstrings from the drive leg or landing leg more active in baseball pitchers? An electromyographic study.

Science.gov (United States)

Erickson, Brandon J; Zaferiou, Antonia; Chalmers, Peter N; Ruby, Deana; Malloy, Phillip; Luchetti, Timothy J; Verma, Nikhil N; Romeo, Anthony A

2017-11-01

Ulnar collateral ligament reconstruction (UCLR) has become a common procedure among baseball players of all levels. There are several graft choices in performing UCLR, one of which is a hamstring (gracilis or semitendinosus) autograft. It is unclear whether the hamstring muscle from a pitcher's drive leg (ipsilateral side of the UCLR) or landing leg (contralateral side of the UCLR) is more active during the pitching motion. We hypothesized that the landing leg semitendinosus will be more electromyographically active than the drive leg. Healthy, elite male pitchers aged 16-21 years were recruited. Sixteen pitchers (average age, 17.6 ± 1.6 years; 67% threw right handed) underwent electromyographic analysis. Pitchers threw 5 fastballs at 100% effort from the wind-up with electromyographic analysis of every pitch. Activation of the semitendinosus and biceps femoris in both legs was compared within pitchers and between pitchers. Hamstring activity was higher in the drive leg than in the landing leg during each phase and in sum, although the difference was significant only during the double support phase (P = .021). On within-pitcher analysis, 10 of 16 pitchers had significantly more sum hamstring activity in the drive leg than in the landing leg, while only 4 of 16 had more activity in the landing leg (P = .043). During the baseball pitch, muscle activity of the semitendinosus was higher in the drive leg than in the landing leg in most pitchers. Surgeons performing UCLR using hamstring autograft should consider harvesting the graft from the pitcher's landing leg to minimize disruption to the athlete's pitching motion. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Improper trunk rotation sequence is associated with increased maximal shoulder external rotation angle and shoulder joint force in high school baseball pitchers.

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Oyama, Sakiko; Yu, Bing; Blackburn, J Troy; Padua, Darin A; Li, Li; Myers, Joseph B

2014-09-01

In a properly coordinated throwing motion, peak pelvic rotation velocity is reached before peak upper torso rotation velocity, so that angular momentum can be transferred effectively from the proximal (pelvis) to distal (upper torso) segment. However, the effects of trunk rotation sequence on pitching biomechanics and performance have not been investigated. The aim of this study was to investigate the effects of trunk rotation sequence on ball speed and on upper extremity biomechanics that are linked to injuries in high school baseball pitchers. The hypothesis was that pitchers with improper trunk rotation sequence would demonstrate lower ball velocity and greater stress to the joint. Descriptive laboratory study. Three-dimensional pitching kinematics data were captured from 72 high school pitchers. Subjects were considered to have proper or improper trunk rotation sequences when the peak pelvic rotation velocity was reached either before or after the peak upper torso rotation velocity beyond the margin of error (±3.7% of the time from stride-foot contact to ball release). Maximal shoulder external rotation angle, elbow extension angle at ball release, peak shoulder proximal force, shoulder internal rotation moment, and elbow varus moment were compared between groups using independent t tests (α ways that may influence injury risk. As such, exercises that reinforce the use of a proper trunk rotation sequence during the pitching motion may reduce the stress placed on the structures around the shoulder joint and lead to the prevention of injuries. © 2014 The Author(s).

Effects of Game Pitch Count and Body Mass Index on Pitching Biomechanics in 9- to 10-Year-Old Baseball Athletes.

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Darke, Jim D; Dandekar, Eshan M; Aguinaldo, Arnel L; Hazelwood, Scott J; Klisch, Stephen M

2018-04-01

Pitching while fatigued and body composition may increase the injury risk in youth and adult pitchers. However, the relationships between game pitch count, biomechanics, and body composition have not been reported for a study group restricted to 9- to 10-year-old athletes. During a simulated game with 9- to 10-year-old athletes, (1) participants will experience biomechanical signs of fatigue, and (2) shoulder and elbow kinetics will correlate with body mass index (BMI). Descriptive laboratory study. Thirteen 9- to 10-year-old youth baseball players pitched a simulated game (75 pitches). Range of motion and muscular output tests were conducted before and after the simulated game to quantify fatigue. Kinematic parameters at foot contact, maximum external rotation, and maximum internal rotation velocity (MIRV), as well as maximum shoulder and elbow kinetics between foot contact and MIRV were compared at pitches 1-5, 34-38, and 71-75. Multivariate analyses of variance were used to test the first hypothesis, and linear regressions were used to test the second hypothesis. MIRV increased from pitches 1-5 to 71-75 ( P = .007), and head flexion at MIRV decreased from pitches 1-5 to 34-38 ( P = .022). Maximum shoulder horizontal adduction, external rotation, and internal rotation torques increased from pitches 34-38 to 71-75 ( P = .031, .023, and .021, respectively). Shoulder compression force increased from pitches 1-5 to 71-75 ( P = .011). Correlations of joint torque/force with BMI were found at every pitch period: for example, shoulder internal rotation ( R 2 = 0.93, P biomechanics for 9- to 10-year-old baseball pitchers and may be used in future studies to improve evidence-based injury prevention guidelines.

Concussion Incidence and Return-to-Play Time in National Basketball Association Players: Results From 2006 to 2014.

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Padaki, Ajay S; Cole, Brian J; Ahmad, Christopher S

2016-09-01

Various research efforts have studied concussions in the National Football League, Major League Baseball, and the National Hockey League. However, no study has investigated the incidence and return-to-play trends in the National Basketball Association (NBA), which this study aims to do. Increased media scrutiny and public awareness, in addition to the institution of a league-wide concussion protocol, may have resulted in more conservative return-to-play practices. Descriptive epidemiology study. All concussions to NBA players that were publicly reported in the media from the beginning of the 2006 NBA season to the end of the 2014 season were included. The incidence and return-to-play statistics were generated by synthesizing information from publicly available records. There were 134 publicly reported concussions to NBA players from the beginning of the 2006 season to the conclusion of the 2014 season, resulting in an average of 14.9 concussions per season. The incidence has not changed significantly during this time span. The average games missed after a concussion from 2006 to 2010 was 1.6, significantly less than the 5.0 games missed from 2011 to 2014, following the institution of the NBA concussion protocol (P = .023). Although the incidence of publicly reported concussions in the NBA has not changed appreciably over the past 9 seasons, the time missed after a concussion has. While players often returned in the same game in the 2006 season, the combination of implemented policy, national coverage, medical staff awareness, and player education may have contributed to players now missing an average of 4 to 6 games after a concussion. A multitude of factors has resulted in more conservative return-to-play practices for NBA players after concussions. © 2016 The Author(s).

Comparing preseason frontal and sagittal plane plyometric programs on vertical jump height in high-school basketball players.

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King, Jeffrey A; Cipriani, Daniel J

2010-08-01

The primary purpose of this study was to evaluate whether frontal plane (FP) plyometrics, which are defined as plyometrics dominated with a lateral component, would produce similar increases in vertical jump height (VJH) compared to sagittal plane (SP) Plyometrics. Thirty-two junior varsity and varsity high-school basketball players participated in 6 weeks of plyometric training. Players participated in either FP or SP plyometrics for the entire study. Vertical jump height was measured on 3 occasions: preintervention (baseline), at week 3 of preparatory training, and at week 6 of training. Descriptive statistics were calculated for VJH. A 2-way analysis of variance (ANOVA) with repeated measures was used to test the difference in mean vertical jump scores using FP and SP training modalities. Results showed a significant effect over time for vertical jump (p training did not have a significant effect on VJH and significant improvement in VJH was seen in subjects participating in SP plyometrics thus reinforcing the specificity principle of training. However, coaches should implement both types of plyometrics because both training modalities can improve power and quickness among basketball players.

Effect of plyometric training on vertical jump height in high school basketball players: randomised control trial

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Chhaya Verma, Lakshmi Subramanium, Vijaya Krishnan

2015-01-01

Full Text Available Background: Plyometric involve high intensity eccentric contraction immediately after a powerful concentric contraction. A vertical leap in basketball also involves rapid & repeated muscle contraction & stretching. Various methods have been used to improve the vertical leap in players, but only few studies mention about plyometrics. Aim: To determine the effect of Plyometric training on vertical jump height in high school basketball players & compare them with their untrained counterparts. Methods and Materials: 144 students were randomly selected & distributed in Group I (Pre-pubertal & Group II (Pubertal which was further divided into Group A (trained players & Group B (untrained students. A gender wise distribution followed this. Plyometric training of 6 weeks was conducted & the vertical jump height pre & post training were recorded & compared. Results: Vertical jump height improved significantly post Plyometric in Group Bcompared to Group A. Boys showed improvement in Group B, however girls were better in Group A. Correlation of BMI with vertical jump height was negative & significant in Group B. Conclusion: Plyometric training brought significant change in untrained students. Boys gained more jump height while girls showed significant increase in jump height during pubertal growth spurt. Also, increased BMI reduced jump height.

Aseptic meningitis outbreak associated with echovirus 30 among high school football players--Los Angeles County, California, 2014.

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Croker, Curtis; Civen, Rachel; Keough, Kathleen; Ngo, Van; Marutani, Amy; Schwartz, Benjamin

2015-01-02

On August 4, 2014, the Acute Communicable Disease Control Program of the Los Angeles County Department of Public Health received a report of three aseptic meningitis cases among football players at a county high school. An investigation was conducted to determine the extent of the outbreak, identify potential exposures, and recommend control measures. An outbreak-associated aseptic meningitis case was defined as an illness of any team or family member with onset during July 28-August 11 with 1) cerebrospinal fluid pleocytosis and negative bacterial culture or 2) an emergency department visit with headache, fever, and stiff neck. Ten cases were identified; nine in males, and one in a female; patient ages ranged from 13 to 17 years. All the patients sought care at an emergency department, and five were hospitalized, resulting in 12 total hospital days. All 10 patients have recovered. Eight patients were football players, and two were siblings of football players. The most affected subgroup was the junior varsity football team, with seven cases out of 57 players (attack rate = 12.3%); the relative risk for aseptic meningitis was higher among players who were linemen than among those who were not linemen (relative risk = 5.4 [p = 0.03]). Of the 10 patients, eight tested positive by polymerase chain reaction for enterovirus, and two were not tested. Echovirus testing was performed at the California Viral and Rickettsial Disease Laboratory. Of the eight specimens testing positive for enterovirus, seven tested positive for echovirus 30, and one specimen could not be typed because of insufficient quantity.

Sex-specific differences in injury types among basketball players

OpenAIRE

Ito E; Iwamoto J; Azuma K; Matsumoto H

2014-01-01

Eri Ito, Jun Iwamoto, Koichiro Azuma, Hideo MatsumotoInstitute for Integrated Sports Medicine, Keio University School of Medicine, Tokyo, JapanAbstract: The purpose of the present study was to investigate sex-specific differences in injury types among basketball players. According to our database, during the 20-year period between October 1991 and June 2011, 1,219 basketball players (640 males and 579 females) consulted our sports medicine clinic; in total, 1,414 injuries in basketball player...

Inadequate pre-season preparation of schoolboy rugby players - a ...

African Journals Online (AJOL)

... in prospective studies at the same schools. The players' knowledge of techniques known to prevent rugby injuries was inadequate and too little attention was paid at the start of the rugby season to training and coaching techniques to reduce injury risk. Coaching errors may therefore have predisposed players to injury.

PERFORMANCE OF HIGH SCHOOL FOOTBALL PLAYERS ON CLINICAL MEASURES OF DEEP CERVICAL FLEXOR ENDURANCE AND CERVICAL ACTIVE RANGE OF MOTION: IS HISTORY OF CONCUSSION A FACTOR?

Science.gov (United States)

Smith, Laura; Ruediger, Thomas; Alsalaheen, Bara; Bean, Ryan

2016-04-01

More than one million adolescent athletes participated in organized high school sanctioned football during the 2014-15 season. These athletes are at risk for sustaining concussion. Although cervical spine active range of motion (AROM) and deep neck flexor endurance may serve a preventative role in concussion, and widespread clinical use of measurements of these variables, reference values are not available for this population. Cost effective, clinically relevant methods for measuring neck endurance are also well established for adolescent athletes. The purpose of this study was to report reference values for deep cervical flexor endurance and cervical AROM in adolescent football players and examine whether differences in these measures exist in high school football players with and without a history of concussion. Concussion history, cervical AROM, and deep neck flexor endurance were measured in 122 high school football players. Reference values were calculated for AROM and endurance measures; association were examined between various descriptive variables and concussion. No statistically significant differences were found between athletes with a history of concussion and those without. A modest inverse correlation was seen between body mass and AROM in the sagittal and transverse planes. The results of this study indicate that the participants with larger body mass had less cervical AROM in some directions. While cervical AROM and endurance measurements may not be adequate to identify adolescents with a history of previous concussions among high school football players. However, if a concussion is sustained, these measures can offer a baseline to examine whether cervical AROM is affected as compared to healthy adolescents. 2c.

High School Football Players' Knowledge and Attitudes About Concussions.

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Anderson, Brit L; Gittelman, Michael A; Mann, Jessica K; Cyriac, RoseAnn L; Pomerantz, Wendy J

2016-05-01

To assess high school (HS) football players' knowledge of concussions and to determine whether increased knowledge is correlated with better attitudes toward reporting concussion symptoms and abstaining from play. Two survey tools were used to assess athletes' knowledge and attitudes about concussions. Surveys collected information about demographics, knowledge about concussions, and attitudes about playing sports after a concussion. All athletes present completed one of the 2 surveys. A knowledge and attitude score for each survey was calculated. Frequencies and mean values were used to characterize the population; regression analysis, analysis of variance, and t tests were used to look for associations. A football camp for HS athletes in the Cincinnati area. Male HS football players from competitive football programs in the Cincinnati area. None. Scores on knowledge and attitude sections; responses to individual questions. One hundred twenty (100%) athletes were enrolled although not every athlete responded to every question. Thirty (25%) reported history of a concussion; 82 (70%) reported receiving prior concussion education. More than 75% correctly recognized all concussion symptoms that were asked, except "feeling in a fog" [n = 63 (53%)]. One hundred nine (92%) recognized a risk of serious injury if they return to play too quickly. Sixty-four (54%) athletes would report symptoms of a concussion to their coach; 62 (53%) would continue to play with a headache from an injury. There was no association between knowledge score and attitude score (P = 0.08). Despite having knowledge about the symptoms and danger of concussions, many HS football athletes in our sample did not have a positive attitude toward reporting symptoms or abstaining from play after a concussion. Physicians should be aware that young athletes may not report concussion symptoms.

Incidence of Staphylococcus aureus nasal colonization and soft tissue infection among high school football players.

Science.gov (United States)

Lear, Aaron; McCord, Gary; Peiffer, Jeffrey; Watkins, Richard R; Parikh, Arpan; Warrington, Steven

2011-01-01

Methicillin-resistant Staphylococcus aureus (MRSA) skin and soft tissue infections have been documented with increasing frequency in both team and individual sports in recent years. It also seems that the level of MRSA skin and soft tissue infections in the general population has increased. One hundred ninety athletes from 6 local high school football teams were recruited for this prospective observational study to document nasal colonization and the potential role this plays in skin and soft tissue infections in football players and, in particular, MRSA infections. Athletes had nasal swabs done before their season started, and they filled out questionnaires regarding potential risk factors for skin and soft tissue infections. Those enrolled in the study were then observed over the course of the season for skin and soft tissue infections. Those infected had data about their infections collected. One hundred ninety of 386 available student athletes enrolled in the study. Forty-four of the subjects had nasal colonization with methicillin-susceptible S. aureus, and none were colonized with MRSA. There were 10 skin and soft tissue infections (8 bacterial and 2 fungal) documented over the course of the season. All were treated as outpatients with oral or topical antibiotics, and none were considered serious. Survey data from the preseason questionnaire showed 21% with skin infection, 11% with methicillin-susceptible S. aureus, and none with MRSA infection during the past year. Three reported a remote history of MRSA infection. We documented an overall skin infection rate of 5.3% among high school football players over a single season. Our results suggest that skin and soft tissue infection may not be widespread among high school athletes in northeast Ohio.

Visual Enhancement for Sports Entertainment by Vision-Based Augmented Reality

OpenAIRE

Uematsu, Yuko; Saito, Hideo

2008-01-01

This paper presents visually enhanced sports entertainment applications: AR Baseball Presentation System and Interactive AR Bowling System. We utilize vision-based augmented reality for getting immersive feeling. First application is an observation system of a virtual baseball game on the tabletop. 3D virtual players are playing a game on a real baseball field model, so that users can observe the game from favorite view points through a handheld monitor with a web camera....

Does posteromedial chondromalacia reduce rate of return to play after ulnar collateral ligament reconstruction?

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Osbahr, Daryl C; Dines, Joshua S; Rosenbaum, Andrew J; Nguyen, Joseph T; Altchek, David W

2012-06-01

Biomechanical studies suggest ulnohumeral chondral and ligamentous overload (UCLO) explains the development of posteromedial chondromalacia (PMC) in throwing athletes with ulnar collateral ligament (UCL) insufficiency. UCL reconstruction reportedly allows 90% of baseball players to return to prior or a higher level of play; however, players with concomitant posteromedial chondromalacia may experience lower rates of return to play. The purpose of this investigation is to determine: (1) the rates of return to play of baseball players undergoing UCL reconstruction and posteromedial chondromalacia; and (2) the complications occurring after UCL reconstruction in the setting of posteromedial chondromalacia. We retrospectively reviewed 29 of 161 (18%) baseball players who were treated for the combined posteromedial chondromalacia and UCL injury. UCL reconstruction was accomplished with the docking technique, and the PMC was addressed with nothing or débridement if Grade 2 or 3 and with débridement or microfracture if Grade 4. The mean age was 19.6 years (range, 16-23 years). Most players were college athletes (76%) and pitchers (93%). We used a modified four-level scale of Conway et al. to assess return to play with 1 being the highest level (return to preinjury level of competition or performance for at least one season after UCL reconstruction). The minimum followup was 24 months (mean, 37 months; range, 24-52 months). Return to play was Level 1 in 22 patients (76%), Level 2 in four patients (14%), Level 3 in two patients (7%), and Level 4 in one (3%) patient. Our data suggest baseball players with concomitant PMC, may have lower rates of return to the same or a higher level of play compared with historical controls. Level IV, case series. See Guidelines for Authors for a complete description of levels of evidence.

Comparison of Indiana High School Football Injury Rates by Inclusion of the USA Football “Heads Up Football” Player Safety Coach

Science.gov (United States)

Kerr, Zachary Y.; Dalton, Sara L.; Roos, Karen G.; Djoko, Aristarque; Phelps, Jennifer; Dompier, Thomas P.

2016-01-01

Background: In Indiana, high school football coaches are required to complete a coaching education course with material related to concussion awareness, equipment fitting, heat emergency preparedness, and proper technique. Some high schools have also opted to implement a player safety coach (PSC). The PSC, an integral component of USA Football’s Heads Up Football (HUF) program, is a coach whose primary responsibility is to ensure that other coaches are implementing proper tackling and blocking techniques alongside other components of the HUF program. Purpose: To compare injury rates in Indiana high school football teams by their usage of a PSC or online coaching education only. Study Design: Cohort study; Level of evidence, 2. Methods: Athletic trainers (ATs) evaluated and tracked injuries at each practice and game during the 2015 high school football season. Players were drawn from 6 teams in Indiana. The PSC group, which used the PSC component, was comprised of 204 players from 3 teams. The “education only” group (EDU), which utilized coaching education only, was composed of 186 players from 3 teams. Injury rates and injury rate ratios (IRRs) were reported with 95% confidence intervals (CIs). Results: During 25,938 athlete-exposures (AEs), a total of 149 injuries were reported, of which 54 (36.2%) and 95 (63.8%) originated from the PSC and EDU groups, respectively. The practice injury rate was lower in the PSC group than the EDU group (2.99 vs 4.83/1000 AEs; IRR, 0.62; 95% CI, 0.40-0.95). The game injury rate was also lower in the PSC group than the EDU group (11.37 vs 26.37/1000 AEs; IRR, 0.43; 95% CI, 0.25-0.74). When restricted to concussions only, the rate was lower in the PSC group (0.09 vs 0.73/1000 AEs; IRR, 0.12; 95% CI, 0.01-0.94), although only 1 concussion was reported in the PSC group. No differences were found in game concussion rates (0.60 vs 4.39/1000 AEs; IRR, 0.14; 95% CI, 0.02-1.11). Conclusion: Findings support the PSC as an effective

Hip and upper extremity kinematics in youth baseball pitchers.

Science.gov (United States)

Holt, Taylor; Oliver, Gretchen D

2016-01-01

The purpose of this study was to examine the relationship between dynamic hip rotational range of motion and upper extremity kinematics during baseball pitching. Thirty-one youth baseball pitchers (10.87 ± 0.92 years; 150.03 ± 5.48 cm; 44.83 ± 8.04 kg) participated. A strong correlation was found between stance hip rotation and scapular upward rotation at maximum shoulder external rotation (r = 0.531, P = 0.002) and at ball release (r = 0.536, P = 0.002). No statistically significant correlations were found between dynamic hip rotational range of motion and passive hip range of motion. Hip range of motion deficits can constrain pelvis rotation and limit energy generation in the lower extremities. Shoulder pathomechanics can then develop as greater responsibility is placed on the shoulder to generate the energy lost from the proximal segments, increasing risk of upper extremity injury. Additionally, it appears that passive seated measurements of hip range of motion may not accurately reflect the dynamic range of motion of the hips through the progression of the pitch cycle.

The Economics of the Duration of the Baseball World Series

Science.gov (United States)

Cassuto, Alexander E.; Lowenthal, Franklin

2007-01-01

This note examines some statistical features of the major league baseball World Series. We show that, based upon actual historical data, we cannot reject the hypothesis that the two World Series teams are evenly matched. Yet, we can also calculate the relative strengths of the teams that would best match the actual outcomes, and we find that those…

Vascular Health in American Football Players: Cardiovascular Risk Increased in Division III Players

Directory of Open Access Journals (Sweden)

Deborah L. Feairheller

2016-01-01

Full Text Available Studies report that football players have high blood pressure (BP and increased cardiovascular risk. There are over 70,000 NCAA football players and 450 Division III schools sponsor football programs, yet limited research exists on vascular health of athletes. This study aimed to compare vascular and cardiovascular health measures between football players and nonathlete controls. Twenty-three athletes and 19 nonathletes participated. Vascular health measures included flow-mediated dilation (FMD and carotid artery intima-media thickness (IMT. Cardiovascular measures included clinic and 24 hr BP levels, body composition, VO2 max, and fasting glucose/cholesterol levels. Compared to controls, football players had a worse vascular and cardiovascular profile. Football players had thicker carotid artery IMT (0.49 ± 0.06 mm versus 0.46 ± 0.07 mm and larger brachial artery diameter during FMD (4.3±0.5 mm versus 3.7±0.6 mm, but no difference in percent FMD. Systolic BP was significantly higher in football players at all measurements: resting (128.2±6.4 mmHg versus 122.4±6.8 mmHg, submaximal exercise (150.4±18.8 mmHg versus 137.3±9.5 mmHg, maximal exercise (211.3±25.9 mmHg versus 191.4±19.2 mmHg, and 24-hour BP (124.9±6.3 mmHg versus 109.8±3.7 mmHg. Football players also had higher fasting glucose (91.6±6.5 mg/dL versus 86.6±5.8 mg/dL, lower HDL (36.5±11.2 mg/dL versus 47.1±14.8 mg/dL, and higher body fat percentage (29.2±7.9% versus 23.2±7.0%. Division III collegiate football players remain an understudied population and may be at increased cardiovascular risk.

Knee Angle and Stride Length in Association with Ball Speed in Youth Baseball Pitchers

Directory of Open Access Journals (Sweden)

Bart van Trigt

2018-05-01

Full Text Available The purpose of this study was to determine whether stride length and knee angle of the leading leg at foot contact, at the instant of maximal external rotation of the shoulder, and at ball release are associated with ball speed in elite youth baseball pitchers. In this study, fifty-two elite youth baseball pitchers (mean age 15.2 SD (standard deviation 1.7 years pitched ten fastballs. Data were collected with three high-speed video cameras at a frequency of 240 Hz. Stride length and knee angle of the leading leg were calculated at foot contact, maximal external rotation, and ball release. The associations between these kinematic variables and ball speed were separately determined using generalized estimating equations. Stride length as percentage of body height and knee angle at foot contact were not significantly associated with ball speed. However, knee angles at maximal external rotation and ball release were significantly associated with ball speed. Ball speed increased by 0.45 m/s (1 mph with an increase in knee extension of 18 degrees at maximal external rotation and 19.5 degrees at ball release. In conclusion, more knee extension of the leading leg at maximal external rotation and ball release is associated with higher ball speeds in elite youth baseball pitchers.

Clinicopathological Evaluation of Chronic Traumatic Encephalopathy in Players of American Football.

Science.gov (United States)

Mez, Jesse; Daneshvar, Daniel H; Kiernan, Patrick T; Abdolmohammadi, Bobak; Alvarez, Victor E; Huber, Bertrand R; Alosco, Michael L; Solomon, Todd M; Nowinski, Christopher J; McHale, Lisa; Cormier, Kerry A; Kubilus, Caroline A; Martin, Brett M; Murphy, Lauren; Baugh, Christine M; Montenigro, Phillip H; Chaisson, Christine E; Tripodis, Yorghos; Kowall, Neil W; Weuve, Jennifer; McClean, Michael D; Cantu, Robert C; Goldstein, Lee E; Katz, Douglas I; Stern, Robert A; Stein, Thor D; McKee, Ann C

2017-07-25

Players of American football may be at increased risk of long-term neurological conditions, particularly chronic traumatic encephalopathy (CTE). To determine the neuropathological and clinical features of deceased football players with CTE. Case series of 202 football players whose brains were donated for research. Neuropathological evaluations and retrospective telephone clinical assessments (including head trauma history) with informants were performed blinded. Online questionnaires ascertained athletic and military history. Participation in American football at any level of play. Neuropathological diagnoses of neurodegenerative diseases, including CTE, based on defined diagnostic criteria; CTE neuropathological severity (stages I to IV or dichotomized into mild [stages I and II] and severe [stages III and IV]); informant-reported athletic history and, for players who died in 2014 or later, clinical presentation, including behavior, mood, and cognitive symptoms and dementia. Among 202 deceased former football players (median age at death, 66 years [interquartile range, 47-76 years]), CTE was neuropathologically diagnosed in 177 players (87%; median age at death, 67 years [interquartile range, 52-77 years]; mean years of football participation, 15.1 [SD, 5.2]), including 0 of 2 pre-high school, 3 of 14 high school (21%), 48 of 53 college (91%), 9 of 14 semiprofessional (64%), 7 of 8 Canadian Football League (88%), and 110 of 111 National Football League (99%) players. Neuropathological severity of CTE was distributed across the highest level of play, with all 3 former high school players having mild pathology and the majority of former college (27 [56%]), semiprofessional (5 [56%]), and professional (101 [86%]) players having severe pathology. Among 27 participants with mild CTE pathology, 26 (96%) had behavioral or mood symptoms or both, 23 (85%) had cognitive symptoms, and 9 (33%) had signs of dementia. Among 84 participants with severe CTE pathology, 75 (89

Opportunities Suspended: The Disparate Impact of Disciplinary Exclusion from School

Science.gov (United States)

Losen, Daniel J.; Gillespie, Jonathan

2012-01-01

Well over three million children, K-12, are estimated to have lost instructional "seat time" in 2009-2010 because they were suspended from school, often with no guarantee of adult supervision outside the school. That's about the number of children it would take to fill every seat in every major league baseball park and every NFL stadium…

A Study of the Interaction between Batting Cage Baseballs and Pitching Machine

Directory of Open Access Journals (Sweden)

Patrick Drane

2018-02-01

Full Text Available Batting cage pitching machines are widely used across the sports of baseball and softball for training and recreation purposes. The balls are specifically designed for the machines and for the environment to ensure high durability and typically do not have seams. Polymeric foam balls are widely used in these automated pitching machines for batting practice in a cage environment and are similar in weight and size compared with the regulation balls used in leagues. The primary objective of this paper is to characterize the polymeric balls and their interaction with the pitching machine. The paper will present measured ball properties and measured relationships between various pitching machine parameters such as wheel speed, and the ratio of wheel speeds on the ball exit velocity and rotation. This paper will also characterize some of the effects of wear on the baseballs and wheels from their prolonged use.

Single season changes in resting state network power and the connectivity between regions distinguish head impact exposure level in high school and youth football players

Science.gov (United States)

Murugesan, Gowtham; Saghafi, Behrouz; Davenport, Elizabeth; Wagner, Ben; Urban, Jillian; Kelley, Mireille; Jones, Derek; Powers, Alex; Whitlow, Christopher; Stitzel, Joel; Maldjian, Joseph; Montillo, Albert

2018-02-01

The effect of repetitive sub-concussive head impact exposure in contact sports like American football on brain health is poorly understood, especially in the understudied populations of youth and high school players. These players, aged 9-18 years old may be particularly susceptible to impact exposure as their brains are undergoing rapid maturation. This study helps fill the void by quantifying the association between head impact exposure and functional connectivity, an important aspect of brain health measurable via resting-state fMRI (rs-fMRI). The contributions of this paper are three fold. First, the data from two separate studies (youth and high school) are combined to form a high-powered analysis with 60 players. These players experience head acceleration within overlapping impact exposure making their combination particularly appropriate. Second, multiple features are extracted from rs-fMRI and tested for their association with impact exposure. One type of feature is the power spectral density decomposition of intrinsic, spatially distributed networks extracted via independent components analysis (ICA). Another feature type is the functional connectivity between brain regions known often associated with mild traumatic brain injury (mTBI). Third, multiple supervised machine learning algorithms are evaluated for their stability and predictive accuracy in a low bias, nested cross-validation modeling framework. Each classifier predicts whether a player sustained low or high levels of head impact exposure. The nested cross validation reveals similarly high classification performance across the feature types, and the Support Vector, Extremely randomized trees, and Gradboost classifiers achieve F1-score up to 75%.

Analysis of Decision Making Process in Moneyball: The Art of Winning an Unfair Game

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Mochamad Sandy Triady

2015-03-01

Full Text Available Billy Beanes’s success in using data-driven decision making in baseball industry is wonderfully written by Michael Lewis in Moneyball. As a general manager in baseball team that were in the bottom position of the league from the financial side to acquire the players, Beane, along with his partner, explored the use of data in choosing the team’s player. They figured out how to determine the worth of every player.The process was not smooth, due to the condition of baseball industry that was not common with using advanced statistic in acquiring   players. Many teams still use the old paradigm that rely on experts’ judgments, intuition, or experience in decision making process. Moneyball approached that using data-driven decision making gave excellent result for Beane’s team. The team won 20 gamessequently in the 2002 season and also spent the lowest cost per win than other teams.This paper attempts to review the principles of Moneyball – The Art of Winning an Unfair Game as a process of decision making and gives what we can learn from the story in order to win the games, the unfair games.

Correlation of glenohumeral internal rotation deficit and total rotational motion to shoulder injuries in professional baseball pitchers.

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Wilk, Kevin E; Macrina, Leonard C; Fleisig, Glenn S; Porterfield, Ronald; Simpson, Charles D; Harker, Paul; Paparesta, Nick; Andrews, James R

2011-02-01

Glenohumeral internal rotation deficit (GIRD) indicates a 20° or greater loss of internal rotation of the throwing shoulder compared with the nondominant shoulder. To determine whether GIRD and a deficit in total rotational motion (external rotation + internal rotation) compared with the nonthrowing shoulder correlate with shoulder injuries in professional baseball pitchers. Case series; Level of evidence, 4. Over 3 competitive seasons (2005 to 2007), passive range of motion measurements were evaluated on the dominant and nondominant shoulders for 170 pitcher-seasons. This included 122 professional pitchers during the 3 seasons of data collection, in which some pitchers were measured during multiple seasons. Ranges of motion were measured with a bubble goniometer during the preseason, by the same examiner each year. External and internal rotation of the glenohumeral joint was assessed with the participant supine and the arm abducted 90° in the plane of the scapula, with the scapula stabilized anteriorly at the coracoid process. The reproducibility of the test methods had an intraclass correlation coefficient of .81. Days in which the player was unable to participate because of injury or surgery were recorded during the season by the medical staff of the team and defined as an injury. Pitchers with GIRD (n = 40) were nearly twice as likely to be injured as those without but without statistical significance (P = .17). Pitchers with total rotational motion deficit greater than 5° had a higher rate of injury. Minor league pitchers were more likely than major league pitchers to be injured. However, when players were injured, major league pitchers missed a significantly greater number of games than minor league pitchers. Compared with pitchers without GIRD, pitchers with GIRD appear to be at a higher risk for injury and shoulder surgery.

Physiologic performance test differences in female volleyball athletes by competition level and player position.

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Schaal, Monique; Ransdell, Lynda B; Simonson, Shawn R; Gao, Yong

2013-07-01

The purpose of this study was to examine physiologic performance test differences by competition level (high school and Division-I collegiate athletes) and player position (hitter, setter, defensive specialist) in 4 volleyball-related tests. A secondary purpose was to establish whether a 150-yd shuttle could be used as a field test to assess anaerobic capacity. Female participants from 4 varsity high school volleyball teams (n = 27) and 2 Division-I collegiate volleyball teams (n = 26) were recruited for the study. Participants completed 4 performance-based field tests (vertical jump, agility T-test, and 150- and 300-yd shuttle runs) after completing a standardized dynamic warm-up. A 2-way multivariate analysis of variance with Bonferroni post hoc adjustments (when appropriate) and effect sizes were used for the analyses. The most important findings of this study were that (a) college volleyball athletes were older, heavier, and taller than high school athletes; (b) high school athletes had performance deficiencies in vertical jump/lower-body power, agility, and anaerobic fitness; (c) lower-body power was the only statistically significant difference in the performance test measures by player position; and (d) the correlation between the 150- and 300-yd shuttle was moderate (r = 0.488). Female high school volleyball players may enhance their ability to play collegiate volleyball by improving their vertical jump, lower-body power, agility, and anaerobic fitness. Furthermore, all player positions should emphasize lower-body power conditioning. These physical test scores provide baseline performance scores that should help strength and conditioning coaches create programs that will address deficits in female volleyball player performance, especially as they transition from high school to college.

As Cutbacks Hit College Sports, Baseball Falls behind in the Count

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Wolverton, Brad

2009-01-01

For two weeks every June, the College World Series showcases one of the National Collegiate Athletic Association's (NCAA's) most popular sports. More than 300,000 fans flock to picturesque Rosenblatt Stadium, in Omaha, with millions more tuning in on ESPN. Ticket sales, which in recent years topped $9-million, make baseball the NCAA's…

« Nous sommes tous frères ». Les valeurs des Elephants de Brother, club de baseball professionnel à Taiwan “We are all Brothers”. The Values of Brother Elephants, professional baseball club in Taiwan

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Jérôme Soldani

2013-06-01

Full Text Available À Taiwan, où le baseball est considéré comme le « sport national », les équipes professionnelles sont la propriété de grandes firmes locales et ne sont pas formellement attachées à une municipalité. Ce sont elles-mêmes de petites entreprises qui proposent, en archétype de société, un mode de fonctionnement interne qui repose sur des valeurs autour desquelles se fédèrent leurs supporters. Basée sur une enquête ethnographique de douze mois, notamment au sein de la formation professionnelle des Elephants de Brother, cette contribution montrera comment celle-ci se donne à voir comme une entreprise structurée autour de valeurs morales entendues comme « traditionnelles » et dont les joueurs de l’équipe sont érigés en parangons. Le modèle d’une famille unie et strictement hiérarchisée est mis en exergue par les propriétaires du club et son iconographie. Mais ces représentations se heurtent à la réalité de la pratique quotidienne et aux affaires de corruption qui sapent régulièrement l’image de la ligue professionnelle taiwanaise.In Taiwan, where baseball is considered as the national sport, professional teams are owned by large local firms and are not formally attached to a municipality. They are themselves small companies offering an archetypal society, whose mode of internal operations are based on values around which to unite their fans. Based on an ethnographic study of twelve months, particularly among the professional team of Brother Elephants, this contribution will show how it is to be seen as an enterprise structured around moral values understood as traditional and whose players are established as paragons. The model of a united family and strictly hierarchical is highlighted by the owners of the club and its iconography. But these representations are faced with the reality of daily practice and corruption that regularly undermine the image of the Taiwanese professional league.

A Highly Miniaturized, Wireless Inertial Measurement Unit for Characterizing the Dynamics of Pitched Baseballs and Softballs

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McGinnis, Ryan S.; Perkins, Noel C.

2012-01-01

Baseball and softball pitch types are distinguished by the path and speed of the ball which, in turn, are determined by the angular velocity of the ball and the velocity of the ball center at the instant of release from the pitcher's hand. While radar guns and video-based motion capture (mocap) resolve ball speed, they provide little information about how the angular velocity of the ball and the velocity of the ball center develop and change during the throwing motion. Moreover, mocap requires measurements in a controlled lab environment and by a skilled technician. This study addresses these shortcomings by introducing a highly miniaturized, wireless inertial measurement unit (IMU) that is embedded in both baseballs and softballs. The resulting “ball-embedded” sensor resolves ball dynamics right on the field of play. Experimental results from ten pitches, five thrown by one softball pitcher and five by one baseball pitcher, demonstrate that this sensor technology can deduce the magnitude and direction of the ball's velocity at release to within 4.6% of measurements made using standard mocap. Moreover, the IMU directly measures the angular velocity of the ball, which further enables the analysis of different pitch types.

A Model of Motor Inhibition for a Complex Skill: Baseball Batting

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Gray, Rob

2009-01-01

The ability to inhibit an ongoing action in response to a signal from the environment is important for many perceptual-motor actions. This paper examines a particular example of this behavior: attempting to inhibit or "check" a swing in baseball batting. A model of motor inhibition in batting is proposed. In the model there are three different…

Opportunities Suspended: The Disparate Impact of Disciplinary Exclusion from School. Executive Summary

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Losen, Daniel J.; Gillespie, Jonathan

2012-01-01

Well over three million children, K-12, are estimated to have lost instructional "seat time" in 2009-2010 because they were suspended from school, often with no guarantee of adult supervision outside the school. That's about the number of children it would take to fill every seat in every major league baseball park and every NFL stadium…

Incidence of Concussion During Practice and Games in Youth, High School, and Collegiate American Football Players.

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Dompier, Thomas P; Kerr, Zachary Y; Marshall, Stephen W; Hainline, Brian; Snook, Erin M; Hayden, Ross; Simon, Janet E

2015-07-01

.80; 95% CI, 0.67-0.96). Youth football had the lowest 1-season concussion risks in 2012 (3.53%) and 2013 (3.13%). The 1-season concussion risk was highest in high school (9.98%) and college (5.54%) in 2012. Football practices were a major source of concussion at all 3 levels of competition. Concussions during practice might be mitigated and should prompt an evaluation of technique and head impact exposure. Although it is more difficult to change the intensity or conditions of a game, many strategies can be used during practice to limit player-to-player contact and other potentially injurious behaviors.

Adolescents and MP3 players: too many risks, too few precautions.

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Vogel, Ineke; Verschuure, Hans; van der Ploeg, Catharina P B; Brug, Johannes; Raat, Hein

2009-06-01

The goal was to assess risky and protective listening behaviors of adolescent users of MP3 players and the association of these behaviors with demographic characteristics and frequency of use. In 2007, 1687 adolescents (12-19 years of age) in 68 classes in 15 Dutch secondary schools were invited to complete questionnaires about their music-listening behaviors. . Ninety percent of participants reported listening to music through earphones on MP3 players; 32.8% were frequent users, 48.0% used high volume settings, and only 6.8% always or nearly always used a noise-limiter. Frequent users were >4 times more likely to listen to high-volume music than were infrequent users, and adolescents in practical prevocational schools were more than twice as likely to listen to high-volume music as were those attending preuniversity education. When using MP3 players, adolescents are very likely to engage in risky listening behaviors and are unlikely to seek protection. Frequent MP3 player use is an indicator of other risky listening behaviors, such as listening at high volumes and failing to use noise-limiters.

MP3 players and hearing loss: adolescents' perceptions of loud music and hearing conservation.

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Vogel, Ineke; Brug, Johannes; Hosli, Esther J; van der Ploeg, Catharina P B; Raat, Hein

2008-03-01

To explore adolescents' behaviors and opinions about exposure to loud music from MP3 players. We conducted a qualitative analysis of focus-group discussions with adolescents aged 12 to 18 years from 2 large secondary schools (1 urban and 1 rural) for pre-vocational and pre-university education. The semi-structured question route was theoretically framed within the protection motivation theory. Most adolescents-especially male students and students from pre-vocational schools-indicated that they often played their MP3 players at maximum volume. Although they appeared to be generally aware of the risks of exposure to loud music, they expressed low personal vulnerability to music-induced hearing loss. Most adolescents said that they would not accept any interference with their music-exposure habits. Interventions should target students from pre-vocational schools and should focus on increasing adolescents' knowledge of the risks of loud music and how to protect themselves. Besides hearing education for adolescents and technical modifications of MP3 players, volume-level regulations for MP3 players may be warranted.

Lumbar Spondylolysis in Juveniles from the Same Family: A Report of Three Cases and a Review of the Literature

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Atsuhisa Yamada

2013-01-01

Full Text Available Spondylolysis is reported as a stress fracture of the pars interarticularis with a strong hereditary basis. Three cases of lumbar spondylolysis in juveniles from the same family are reported, and the genetics of the condition are reviewed. The first boy, a 13-year-old soccer player, was diagnosed with terminal stage L5 bilateral spondylolysis with grade 1 slippage. The second boy, a 10-year-old baseball player, had terminal stage right side unilateral spondylolysis. The third boy, also a 10-year-old baseball player, was diagnosed with early stage bilateral L5 spondylolysis. The second and third boys are identical twins, and all three cases exhibited concomitant spina bifida occulta. Lumbar spondylolysis has a strong hereditary basis and is reported to be an autosomal dominant condition.

Lumbar Spondylolysis in Juveniles from the Same Family: A Report of Three Cases and a Review of the Literature

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Yamada, Atsuhisa; Sairyo, Koichi; Shibuya, Isao; Kato, Ko; Dezawa, Akira

2013-01-01

Spondylolysis is reported as a stress fracture of the pars interarticularis with a strong hereditary basis. Three cases of lumbar spondylolysis in juveniles from the same family are reported, and the genetics of the condition are reviewed. The first boy, a 13-year-old soccer player, was diagnosed with terminal stage L5 bilateral spondylolysis with grade 1 slippage. The second boy, a 10-year-old baseball player, had terminal stage right side unilateral spondylolysis. The third boy, also a 10-year-old baseball player, was diagnosed with early stage bilateral L5 spondylolysis. The second and third boys are identical twins, and all three cases exhibited concomitant spina bifida occulta. Lumbar spondylolysis has a strong hereditary basis and is reported to be an autosomal dominant condition. PMID:24191211

Female adolescent elite handball players are more susceptible to shoulder problems than their male counterparts.

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Asker, Martin; Holm, Lena W; Källberg, Henrik; Waldén, Markus; Skillgate, Eva

2018-02-10

Shoulder problems are frequent among senior elite handball players. The objective of this study was to assess the prevalence of shoulder problems among adolescent elite handball players and to investigate potential differences in gender, school grade, playing position and playing level. During the 2014 and 2015 pre-season periods, 471 players (age 15-18 years, 54% female) completed a comprehensive baseline questionnaire regarding history of any shoulder pain and shoulder problems experienced during the past season. The players were monitored weekly for one competition season (September-April) regarding shoulder problems and the amount of match and training. Generalised linear models with a binomial link function were used to calculate a prevalence ratio (PR) with 95% confidence interval (CI) to compare the subgroups of players. In total, 110 players (23%) reported having substantial shoulder problems (defined as moderate/severe reduction in training volume, or moderate/severe reduction in performance, or complete inability to participate) at some point during the follow-up season, of which almost half reported complete inability to participate. Of those players reporting substantial problems, 43% (95% CI 39-48) did so for at least 3 consecutive weeks during the season. The prevalence was significantly higher in female players (PR 1.46, 95% 1.04-2.06) and in backcourt players (PR 1.58, 95% CI 1.08-2.32), but no differences were found for school grade (PR 1.21 95% CI 0.88-1.67) or playing level (PR 1.09 95% CI 0.76-1.56). The prevalence of substantial shoulder problems in adolescent elite handball players is high, especially among females, and this warrants further studies on risk factors for shoulder injury and the development of prevention strategies in handball players already before the age of 15. These findings also highlight the importance of introducing a clinical monitoring programme on a routine basis and improving the medical support, taking gender

Incidence of Stingers in Young Rugby Players.

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Kawasaki, Takayuki; Ota, Chihiro; Yoneda, Takeshi; Maki, Nobukazu; Urayama, Shingo; Nagao, Masashi; Nagayama, Masataka; Kaketa, Takefumi; Takazawa, Yuji; Kaneko, Kazuo

2015-11-01

A stinger is a type of neurapraxia of the cervical roots or brachial plexus and represents a reversible peripheral nerve injury. The incidence of and major risk factors for stingers among young rugby players remain uninvestigated. To investigate the incidence, symptoms, and intrinsic risk factors for stingers in elite rugby union teams of young players. Descriptive epidemiology study. A total of 569 male rugby players, including 358 players from 7 high school teams and 211 players from 2 university teams, were investigated using self-administered preseason and postseason questionnaires. The prevalence of a history of stingers was 33.9% (95% CI, 30.3-37.9), and 20.9% (119/569) of players experienced at least 1 episode of a stinger during the season (34.2 [95% CI, 26.2-42.1] events per 1000 player-hours of match exposure). The reinjury rate for stingers per season was 37.3% (95% CI, 30.4-44.2). Using the multivariate Poisson regression method, a history of stingers in the previous season and the grade and position of the player were found to be risk factors for stingers during the current season. The mean severity of injury was 2.9 days, with 79.3% (191/241) of the players not losing any time from playing after sustaining a stinger injury and 5.8% (14/241) of the players recovering within more than 14 days. The most frequent symptom was numbness in the unilateral upper extremity, and the most severe symptom was weakness of grasping (mean severity, 6 days). A logistic regression analysis indicated that a history of stingers in the previous season and an injury with more than 3 symptoms, especially motor weakness, were correlated with the severity of injury. Young rugby players with a history of stingers have a significantly high rate of repeat injuries. Although nearly 80% of the players experienced only minimal (0-1 day) time loss injuries, neurological deficits sometimes last beyond 1 month. A history of stingers was identified to be the strongest risk factor for

A Multisport Epidemiologic Comparison of Anterior Cruciate Ligament Injuries in High School Athletics

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Joseph, Allan M.; Collins, Christy L.; Henke, Natalie M.; Yard, Ellen E.; Fields, Sarah K.; Comstock, R. Dawn

2013-01-01

Background: The knee joint is the second most commonly injured body site after the ankle and the leading cause of sport-related surgeries. Knee injuries, especially of the anterior cruciate ligament (ACL), are among the most economically costly sport injuries, frequently requiring expensive surgery and rehabilitation. Objective: To investigate the epidemiology of ACL injuries among high school athletes by sport and sex. Design: Descriptive epidemiology study. Main Outcome Measure(s): Using an Internet-based data-collection tool, Reporting Information Online (RIO), certified athletic trainers from 100 nationally representative US high schools reported athlete-exposure and injury data for athletes from 9 sports during the 2007/08–2011/12 academic years. The outcome of interest in this study was ACL injuries. Results: During the study period, 617 ACL injuries were reported during 9 452 180 athlete exposures (AEs), for an injury rate of 6.5 per 100 000 AEs. Nationally, in the 9 sports studied, an estimated 215 628 ACL injuries occurred during the study period. The injury rate was higher in competition (17.6) than practice (2.4; rate ratio [RR] = 7.3, 95% confidence interval [CI] = 6.08, 8.68). Girls' soccer had the highest injury rate (12.2) followed by boys' football (11.1), with boys' basketball (2.3) and boys' baseball (0.7) having the lowest rates. In sex-comparable sports, girls had a higher rate (8.9) than boys (2.6; RR = 3.4, 95% CI = 2.64, 4.47). Overall, 76.6% of ACL injuries resulted in surgery. The most common mechanisms of injury were player-to-player contact (42.8%) and no contact (37.9%). Conclusions: Anterior cruciate ligament injury rates vary by sport, sex, and type of exposure. Recognizing such differences is important when evaluating the effectiveness of evidence-based, targeted prevention efforts. PMID:24143905

Pitching Emotions: The Interpersonal Effects of Emotions in Professional Baseball.

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Cheshin, Arik; Heerdink, Marc W; Kossakowski, Jolanda J; Van Kleef, Gerben A

2016-01-01

Sports games are inherently emotional situations, but surprisingly little is known about the social consequences of these emotions. We examined the interpersonal effects of emotional expressions in professional baseball. Specifically, we investigated whether pitchers' facial displays influence how pitches are assessed and responded to. Using footage from the Major League Baseball World Series finals, we isolated incidents where the pitcher's face was visible before a pitch. A pre-study indicated that participants consistently perceived anger, happiness, and worry in pitchers' facial displays. An independent sample then predicted pitch characteristics and batter responses based on the same perceived emotional displays. Participants expected pitchers perceived as happy to throw more accurate balls, pitchers perceived as angry to throw faster and more difficult balls, and pitchers perceived as worried to throw slower and less accurate balls. Batters were expected to approach (swing) when faced with a pitcher perceived as happy and to avoid (no swing) when faced with a pitcher perceived as worried. Whereas previous research focused on using emotional expressions as information regarding past and current situations, our work suggests that people also use perceived emotional expressions to predict future behavior. Our results attest to the impact perceived emotional expressions can have on professional sports.

A Highly Miniaturized, Wireless Inertial Measurement Unit for Characterizing the Dynamics of Pitched Baseballs and Softballs

Directory of Open Access Journals (Sweden)

Noel C. Perkins

2012-08-01

Full Text Available Baseball and softball pitch types are distinguished by the path and speed of the ball which, in turn, are determined by the angular velocity of the ball and the velocity of the ball center at the instant of release from the pitcher’s hand. While radar guns and video-based motion capture (mocap resolve ball speed, they provide little information about how the angular velocity of the ball and the velocity of the ball center develop and change during the throwing motion. Moreover, mocap requires measurements in a controlled lab environment and by a skilled technician. This study addresses these shortcomings by introducing a highly miniaturized, wireless inertial measurement unit (IMU that is embedded in both baseballs and softballs. The resulting “ball-embedded” sensor resolves ball dynamics right on the field of play. Experimental results from ten pitches, five thrown by one softball pitcher and five by one baseball pitcher, demonstrate that this sensor technology can deduce the magnitude and direction of the ball’s velocity at release to within 4.6% of measurements made using standard mocap. Moreover, the IMU directly measures the angular velocity of the ball, which further enables the analysis of different pitch types.

Instructional Design for Accelerated Macrocognitive Expertise in the Baseball Workplace.

Science.gov (United States)

Fadde, Peter J

2016-01-01

The goal of accelerating expertise can leave researchers and trainers in human factors, naturalistic decision making, sport science, and expertise studies concerned about seemingly insufficient application of expert performance theories, findings and methods for training macrocognitive aspects of human performance. Video-occlusion methods perfected by sports expertise researchers have great instructional utility, in some cases offering an effective and inexpensive alternative to high-fidelity simulation. A key problem for instructional designers seems to be that expertise research done in laboratory and field settings doesn't get adequately translated into workplace training. Therefore, this article presents a framework for better linkage of expertise research/training across laboratory, field, and workplace settings. It also uses a case study to trace the development and implementation of a macrocognitive training program in the very challenging workplace of the baseball batters' box. This training, which was embedded for a full season in a college baseball team, targeted the perceptual-cognitive skill of pitch recognition that allows expert batters to circumvent limitations of human reaction time in order to hit a 90 mile-per-hour slider. While baseball batting has few analogous skills outside of sports, the instructional design principles of the training program developed to improve batting have wider applicability and implications. Its core operational principle, supported by information processing models but challenged by ecological models, decouples the perception-action link for targeted part-task training of the perception component, in much the same way that motor components routinely are isolated to leverage instructional efficiencies. After targeted perceptual training, perception and action were recoupled via transfer-appropriate tasks inspired by in situ research tasks. Using NCAA published statistics as performance measures, the cooperating team

Instructional Design for Accelerated Macrocognitive Expertise in the Baseball Workplace

Directory of Open Access Journals (Sweden)

Peter J. Fadde

2016-03-01

Full Text Available The goal of accelerating expertise can leave researchers and trainers in human factors, naturalistic decision making, sport science, and expertise studies concerned about seemingly insufficient application of expert performance theories, findings and methods for training macrocognitive aspects of human performance. Video-occlusion methods perfected by sports expertise researchers have great instructional utility, in some cases offering an effective and inexpensive alternative to high-fidelity simulation. A key problem for instructional designers seems to be that expertise research done in laboratory and field settings doesn’t get adequately translated into workplace training. Therefore, this article presents a framework for better linkage of expertise research/training across laboratory, field, and workplace settings. It also uses a case study to trace the development and implementation of a macrocognitive training program in the very challenging workplace of the baseball batters’ box. This training, which was embedded for a full season in a college baseball team, targeted the perceptual-cognitive skill of pitch recognition that allows expert batters to circumvent limitations of human reaction time in order to hit a 90 mile-per-hour slider. While baseball batting has few analogous skills outside of sports, the instructional design principles of the training program developed to improve batting have wider applicability and implications. Its core operational principle, supported by information processing models but challenged by ecological models, decouples the perception-action link for targeted part-task training of the perception component, in much the same way that motor components routinely are isolated to leverage instructional efficiencies. After targeted perceptual training, perception and action were recoupled via transfer-appropriate tasks inspired by in situ research tasks. Using NCAA published statistics as performance measures

Head Impact Exposure and Neurologic Function of Youth Football Players.

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Munce, Thayne A; Dorman, Jason C; Thompson, Paul A; Valentine, Verle D; Bergeron, Michael F

2015-08-01

Football players are subjected to repetitive impacts that may lead to brain injury and neurologic dysfunction. Knowledge about head impact exposure (HIE) and consequent neurologic function among youth football players is limited. This study aimed to measure and characterize HIE of youth football players throughout one season and explore associations between HIE and changes in selected clinical measures of neurologic function. Twenty-two youth football players (11-13 yr) wore helmets outfitted with a head impact telemetry (HIT) system to quantify head impact frequency, magnitude, duration, and location. Impact data were collected for each practice (27) and game (9) in a single season. Selected clinical measures of balance, oculomotor performance, reaction time, and self-reported symptoms were assessed before and after the season. The median individual head impacts per practice, per game, and throughout the entire season were 9, 12, and 252, respectively. Approximately 50% of all head impacts (6183) had a linear acceleration between 10g and 20g, but nearly 2% were greater than 80g. Overall, the head impact frequency distributions in this study population were similar in magnitude and location as in high school and collegiate football, but total impact frequency was lower. Individual changes in neurologic function were not associated with cumulative HIE. This study provides a novel examination of HIE and associations with short-term neurologic function in youth football and notably contributes to the limited HIE data currently available for this population. Whereas youth football players can experience remarkably similar head impact forces as high school players, cumulative subconcussive HIE throughout one youth football season may not be detrimental to short-term clinical measures of neurologic function.

Football Players' Head-Impact Exposure After Limiting of Full-Contact Practices.

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Broglio, Steven P; Williams, Richelle M; O'Connor, Kathryn L; Goldstick, Jason

2016-07-01

Sporting organizations limit full-contact football practices to reduce concussion risk and based on speculation that repeated head impacts may result in long-term neurodegeneration. To directly compare head-impact exposure in high school football players before and after a statewide restriction on full-contact practices. Cross-sectional study. High school football field. Participants were varsity football athletes from a single high school. Before the rule change, 26 athletes (age = 16.2 ± 0.8 years, height = 179.6 ± 6.4 cm, weight = 81.9 ± 13.1 kg) participated. After the rule change, 24 athletes (age = 15.9 ± 0.8 years, height = 178.3 ± 6.5 cm, weight = 76.2 ± 11.6 kg) participated. Nine athletes participated in both years of the investigation. Head-impact exposure was monitored using the Head Impact Telemetry System while the athletes participated in football games and practices in the seasons before and after the rule change. Head-impact frequency, location, and magnitude (ie, linear acceleration, rotational acceleration, and Head Impact Telemetry severity profile [HITsp], respectively) were measured. A total of 15 398 impacts (592 impacts per player per season) were captured before the rule change and 8269 impacts (345 impacts per player per season) after the change. An average 42% decline in impact exposure occurred across all players, with practice-exposure declines occurring among linemen (46% decline); receivers, cornerbacks, and safeties (41% decline); and tight ends, running backs (including fullbacks), and linebackers (39% decline). Impact magnitudes remained largely unchanged between the years. A rule change limiting full-contact high school football practices appears to have been effective in reducing head-impact exposure across all players, with the largest reduction occurring among linemen. This finding is likely associated with the rule modification, particularly because the coaching staff and offensive scheme remained consistent, yet how

Are You Listening to Me? Space, Context and Perspective in the Regulation of Mp3 Players and Cell Phones in Secondary School

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Domitrek, Julie; Raby, Rebecca

2008-01-01

Recently, there has been much media coverage about cell phone and personal music player usage in schools, including in the Toronto and Whitton regions. However, there is little literature on how students and teachers view rules on the use of such electronic devices. Using data gathered from focus groups with students in Toronto and Whitton and…

Sport Nutrition Knowledge, Behaviors and Beliefs of High School Soccer Players

Directory of Open Access Journals (Sweden)

Melinda M. Manore

2017-04-01

Full Text Available For adolescent athletes (14–18 years, data on sport nutrition knowledge, behaviors and beliefs are limited, especially based on sex, race/ethnicity and socioeconomic status. High school soccer players (n = 535; 55% female; 51% White, 41% Latino; 41% National School Lunch Program (NSLP participants (80% Latino completed two questionnaires (demographic/health history and sport nutrition. The sport nutrition knowledge score was 45.6% with higher scores in NSLP-Whites vs. NSLP-Latinos (p < 0.01. Supplement knowledge differed by sex (16% lower in females; p = 0.047 and race/ethnicity (33% lower in Latinos; p < 0.001. Breakfast consumption was 57%; females ate breakfast less (50% than males (60%; p < 0.001; NSLP-participants ate breakfast less (47% than non-NSLP (62%; p < 0.001. Supplement use was 46%, with Latinos using more supplements than Whites do (p = 0.016. Overall, 30% used protein shakes, with females using less than males (p = 0.02, while use was twice as likely in Latino vs. White (p = 0.03. Overall, 45% reported their nutrient requirements were different from non-athlete peers. Latinos were less likely (p = 0.03 to report that their diet met nutritional requirements, but more than twice as likely to report that nutritional supplements were necessary for training (p < 0.001. Adolescent athletes, especially females and Latinos, would benefit from sport nutrition education that enhances food selection skills for health and sport performance.

A cross-sport comparison of performance-based outcomes of professional athletes following primary microfracture of the knee.

Science.gov (United States)

Schallmo, Michael S; Singh, Sameer K; Barth, Kathryn A; Freshman, Ryan D; Mai, Harry T; Hsu, Wellington K

2018-05-08

The purpose of this study was to compare performance-based outcomes among professional athletes in four major North American sports following microfracture to treat symptomatic chondral defects of the knee. Major League Baseball (MLB), National Basketball Association (NBA), National Football League (NFL), and National Hockey League (NHL) athletes who underwent primary unilateral microfracture of the knee were identified through a previously reported protocol based on public sources. Successful return-to-play was defined as returning for at least one professional regular season game after surgery. Regular season player statistics and sport-specific performance scores were compiled for each player. Each player served as his own control, with the season prior to surgery defined as baseline. Comparisons across sports were enabled by adjusting for expected season and career length differences between sports and by calculating percent changes in performance. One hundred thirty one professional athletes who underwent microfracture were included. One hundred three athletes (78.6%) successfully returned to play. The ratio of games started-to-games played before surgery was found to be a significant positive independent predictor of returning (p = 0.002). Compared with their preoperative season, basketball and baseball players demonstrated significantly decreased performance one season after surgery (-14.8%, p = 0.029 and -12.9%, p = 0.002, respectively) that was recoverable to baseline by postoperative seasons 2-3 for baseball players but not for basketball players (-9.7%, p = 0.024). Knee microfracture surgery is associated with a high rate of return to the professional level. However, the impact of this procedure on postoperative performance varied significantly depending on sport. Copyright © 2018. Published by Elsevier B.V.

Traumatic Brain and Spinal Cord Fatalities Among High School and College Football Players - United States, 2005-2014.

Science.gov (United States)

Kucera, Kristen L; Yau, Rebecca K; Register-Mihalik, Johna; Marshall, Stephen W; Thomas, Leah C; Wolf, Susanne; Cantu, Robert C; Mueller, Frederick O; Guskiewicz, Kevin M

2017-01-06

An estimated 1.1 million high school and 75,000 college athletes participate in tackle football annually in the United States. Football is a collision sport; traumatic injuries are frequent (1,2), and can be fatal (3). This report updates the incidence and characteristics of deaths caused by traumatic brain injury and spinal cord injury (4) in high school and college football and presents illustrative case descriptions. Information was analyzed from the National Center for Catastrophic Sport Injury Research (NCCSIR). During 2005-2014, a total of 28 deaths (2.8 deaths per year) from traumatic brain and spinal cord injuries occurred among high school (24 deaths) and college football players (four deaths) combined. Most deaths occurred during competitions and resulted from tackling or being tackled. All four of the college deaths and 14 (58%) of the 24 high school deaths occurred during the last 5 years (2010-2014) of the 10-year study period. These findings support the need for continued surveillance and safety efforts (particularly during competition) to ensure proper tackling techniques, emergency planning for severe injuries, availability of medical care onsite during competitions, and assessment that it is safe to return to play following a concussion.

Differences in game reading between selected and non-selected youth soccer players.

Science.gov (United States)

Den Hartigh, Ruud J R; Van Der Steen, Steffie; Hakvoort, Bas; Frencken, Wouter G P; Lemmink, Koen A P M

2018-02-01

Applying an established theory of cognitive development-Skill Theory-the current study compares the game-reading skills of youth players selected for a soccer school of a professional soccer club (n = 49) and their non-selected peers (n = 38). Participants described the actions taking place in videos of soccer game plays, and their verbalisations were coded using Skill Theory. Compared to the non-selected players, the selected players generally demonstrated higher levels of complexity in their game-reading, and structured the information of game elements-primarily the player, teammate and field-at higher complexity levels. These results demonstrate how Skill Theory can be used to assess, and distinguish game-reading of youth players with different expertise, a skill important for soccer, but also for other sports.

Epidemiology of injuries in female high school soccer players.

African Journals Online (AJOL)

... commonly injured. Keywords: Epidemiology, soccer injuries, youth ... fun and enjoyment while burning up calories especially when electronic devices ... ture on female soccer players has also grown significant- ly9,10. In the last decade, ...

Talented High School Football Players’ Perception of Talent Identification Criteria

Directory of Open Access Journals (Sweden)

Vazjwar Matin

2017-06-01

Full Text Available Talent identification (TID is a major part of top-level football. Even so, most studies of talented players are skewed towards exploring the work of coaches who are already dealing with pre-defined “talented performers” and not a broader range of players, such as high school students in sport specialisation programs (SSP and elite sport specialisation programs (ESSP. In this study, we explore which skills high school players find most important, how they assess their own skills compared to their schoolmates and which skills their school and club coaches find most important, comparing: girls and boys, an SSP and an ESSP school and players playing top-level versus low-level football. Included in this study were 111 high school football players (81 boys and 30 girls representing one SSP and one ESSP. The results showed that the players ranked mental and tactical skills as most important compared to the school and club coach who ranked, respectively, technical and physical, and tactical and technical skills as most important. Girls considered both tactical and physical skills significantly (<0.01 more important than boys. Players from SSP considered mental skills as significantly more important, while the ESSP players considered the tactical skills as significantly more important. Furthermore, the top-level players considered technical and mental skills as significantly more important. These results could indicate that gender, school type and playing level could affect the players’ perception of the most important skills in TID.

Trunk Muscle Function Deficit in Youth Baseball Pitchers With Excessive Contralateral Trunk Tilt During Pitching.

Science.gov (United States)

Oyama, Sakiko; Waldhelm, Andrew G; Sosa, Araceli R; Patel, Ravina R; Kalinowski, Derick L

2017-09-01

Pitching technique is one of many factors that affect injury risk. Exhibiting excessive contralateral trunk tilt (CLT) during pitching has been linked to higher ball speed but also to increased joint loading. Deficit in trunk muscle strength has been suggested as an underlying cause of this movement pattern. The purpose of the study was to compare trunk muscle strength between youth baseball pitchers with varying degree of CLT during pitching. Cross-sectional study. Baseball practice fields. Twenty-eight youth baseball pitchers. Pitching technique was captured using a video camera. Based on the 2-dimensional trunk contralateral flexion angle, pitchers were categorized into low (30 degrees) CLT groups. Maximum isometric strength tests for trunk flexion, extension, and bilateral rotation, measured using a dynamometer. The pitchers with high CLT (n = 10) had longer pitching experience (P = 0.014), produced higher ball speed (P = 0.003) compared with the pitchers with moderate (n = 10) and low (n = 8) CLT, but demonstrated greater asymmetry in trunk rotation strength (relative weakness in rotation strength toward dominant side) compared with the pitchers with low CLT (P = 0.015). Excessive CLT may be a strategy that young pitchers learn to achieve higher ball velocity but also may be associated with imbalance between the oblique muscles on dominant and nondominant side, which may be acquired from repetitive pitching. Strengthening and emphasizing the use of dominant side oblique muscles may keep pitchers from leaning excessively during pitching and thus decrease joint loading.

Sex-specific differences in injury types among basketball players

Directory of Open Access Journals (Sweden)

Ito E

2014-12-01

Full Text Available Eri Ito, Jun Iwamoto, Koichiro Azuma, Hideo MatsumotoInstitute for Integrated Sports Medicine, Keio University School of Medicine, Tokyo, JapanAbstract: The purpose of the present study was to investigate sex-specific differences in injury types among basketball players. According to our database, during the 20-year period between October 1991 and June 2011, 1,219 basketball players (640 males and 579 females consulted our sports medicine clinic; in total, 1,414 injuries in basketball players (729 injuries in males and 685 injuries in females were recorded. The mean age of patients was 19.6 years. The most common injury site was the knee, followed by the foot and ankle, lower back, and upper extremities. There was a higher proportion of female players presenting with a knee injury, compared with male players (50.4% vs 41.7%, and a lower proportion of female players presenting with an upper extremity injury (5.1% vs 9.7%. The proportion of anterior cruciate ligament injury in the 10–19-year-old age group was higher among female players than among male players (45.9% vs 22.1%, while the proportions of Osgood–Schlatter disease in the 10–19-year-old age group and jumper's knee (patellar and femoral tendinopathy in the 20–29-year-old age group were higher among male players than among female players (12.5% vs 1.8% and 14.6% vs 3.7%, respectively. However, the proportions of other injuries did not differ significantly between male and female players. The present observational study, which was performed using a retrospective case-series design, showed the existence of sex-specific differences in knee injuries sustained while participating in basketball.Keywords: sports injury, sex, anterior cruciate ligament injury, Osgood–Schlatter disease, basketball

Training activities and injuries in English youth academy and schools rugby union.

Science.gov (United States)

Palmer-Green, Deborah S; Stokes, Keith A; Fuller, Colin W; England, Michael; Kemp, Simon P T; Trewartha, Grant

2015-02-01

All rugby training activities carry an injury risk, but in the training environment these injury risks should be more controllable than during matches. To (1) describe the incidence, severity, anatomic location, and type of youth rugby training injuries; (2) determine the injury events and type of training activities associated with injuries; and (3) compare 2 levels of play (professional academy vs school) within English youth rugby union. Cohort study; Level of evidence, 2. A 2-season (2006-2007 and 2007-2008) study recorded exposure to training activities and time-loss injuries in male youth rugby union players (age range, 16-18 years) from 12 English Premiership academies (250 player-seasons) and 7 schools (222 player-seasons). Players from the Premiership academies, associated with the top-level professional clubs in England, represented the elite level of youth rugby; the school players were from established rugby-playing schools but were overall considered at a lower level of play. There was a trend for training injury incidence to be lower for the academy group (1.4/1000 player-hours; 95% CI, 1.0-1.7) compared with the school group (2.1/1000 player-hours; 95% CI, 1.4-2.9) (P = .06). Injuries to the ankle/heel and thigh were most common in academy players and injuries to the lumbar spine and ankle/heel region most common in school players. The training activities responsible for injury differed between the 2 groups: technical skills (scrummaging) for school players and contact skills (defense and ruck/maul drills) for academy players. For injury risk management in youth rugby, coaches of school players should focus on the development of the correct technique during practice of technical skills such as scrummaging, weight training, and skills training, and coaches of academy players should consider the extent to which contact drills are necessary during training. © 2014 The Author(s).

An investigation of player to player character identification via personal pronouns

DEFF Research Database (Denmark)

Hichens, Michael; Drachen, Anders; Richards, Deborah

2012-01-01

The player character is an important feature of many games, where it is through the character that the player interacts with game world. There has been considerable interest in the relationship between the player and the player character. Much of this work has examined the identification of players......, third) as an indication of the relationship between player and character. Results indicate that the presence of story and information about the player character had no effect on identification with the plater character. However, characteristics of the players, particularly gender and general experience...... in playing video games, did have a statistically significant affect, indicating that different levels of identification are more dependent on the player than on the game. This indicates that players are not a homogeneous group with respect to player character identification and is an important consideration...

Streaming-plasma measurements in the Baseball II-T mirror experiment

International Nuclear Information System (INIS)

Damm, C.C.; Foote, J.H.; Futch, A.H.; Goodman, R.K.; Hornady, R.S.; Osher, J.E.; Porter, G.D.

1977-01-01

The warm plasma from a deuterium-loaded titanium washer gun, streaming along magnetic-field lines through the steady-state magnetic well of Baseball II, has been examined for its suitability in this experimental situation as a target plasma for hot-ion buildup experiments and for microinstability control. The gun was positioned near the magnetic axis outside the mirror region. Measurements were made with gridded, end-loss detectors placed outside the opposite mirror, a microwave interferometer, a beam-attenuation detector, and other diagnostics

Comparisons of eccentric knee flexor strength and asymmetries across elite, sub-elite and school level cricket players

Directory of Open Access Journals (Sweden)

Wade J. Chalker

2016-02-01

Full Text Available Background. There has been a continual increase in injury rates in cricket, with hamstring strain injuries (HSIs being the most prominent. Eccentric knee flexor weakness and bilateral asymmetries are major modifiable risk factors for future HSIs. However, there is a lack of data relating to eccentric hamstring strength in cricket at any skill level. The objective of this study was to compare eccentric knee flexor strength and bilateral asymmetries in elite, sub-elite and school level cricket players; and to determine if playing position and limb role influenced these eccentric knee flexor strength indices. Methods. Seventy four male cricket players of three distinct skill levels performed three repetitions of the Nordic hamstring exercise on the experimental device. Strength was assessed as the absolute and relative mean peak force output for both limbs, with bilateral asymmetries. Differences in mean peak force outputs between skill level and playing positions were measured. Results. There were no significant differences between elite, sub-elite and school level athletes for mean peak force and bilateral asymmetries of the knee flexors. There were no significant differences observed between bowler’s and batter’s mean peak force and bilateral asymmetries. There were no significant differences between front and back limb mean peak force outputs. Discussion. Skill level, playing position and limb role appeared to have no significant effect on eccentric knee flexor strength and bilateral asymmetries. Future research should seek to determine whether eccentric knee flexor strength thresholds are predictive of HSIs in cricket and if specific eccentric knee flexor strengthening can reduce these injuries.

Effect on High versus Low Fidelity Haptic Feedback in a Virtual Reality Baseball Simulation

DEFF Research Database (Denmark)

Ryge, Andreas Nicolaj; Thomsen, Lui Albæk; Berthelsen, Theis

2017-01-01

In this paper we present a within-subjects study (n=26) comparing participants' experience of three kinds of haptic feedback (no haptic feedback, low fidelity haptic feedback and high fidelity haptic feedback) simulating the impact between a virtual baseball bat and ball. We noticed some minor ef...

Participants in School-Sponsored and Independent Sports: Perceptions of Self and Family.

Science.gov (United States)

Browne, Beverly A.; Francis, Sally K.

1993-01-01

Examined perceptions of social competence and family dynamics among adolescent participants in school-sponsored and independent sports (baseball and skateboarding). Findings from 271 adolescents revealed that perceptions of social competence were differentially related to degree of sports involvement and perceived skill but were not related to…

Association Between Portable Music Player Use and Hearing Loss Among Children of School Age in the Netherlands.

Science.gov (United States)

le Clercq, Carlijn M P; Goedegebure, André; Jaddoe, Vincent W V; Raat, Hein; Baatenburg de Jong, Robert J; van der Schroeff, Marc P

2018-06-14

), but listening time and duration were not. There was no association of music exposure with high-frequency notches. In this study, 14.2% of school-aged children showed audiometric notches or high-frequency hearing loss. This hearing impairment is already present prior to exposure to known noise hazards, such as club and concert attendance, and may have lifelong consequences. Repeated measurements are needed to confirm the association of portable music player use with hearing impairment in children.

Using Elite Athletes to Promote Drug Abstinence: Evaluation of a Single-Session School-Based Drug Use Prevention Program Delivered by Junior Hockey Players

Science.gov (United States)

Wong, Jennifer

2016-01-01

School-based substance use prevention programs are a common method to approaching drug use in youths. Project SOS is a single-session drug prevention program developed by police officers and delivered by elite junior hockey players to students in grades 6 and 7. The current study evaluates the effects of Project SOS at achieving its objectives of…

Baseball Stadium Design: Teaching Engineering Economics and Technical Communication in a Multi-Disciplinary Setting.

Science.gov (United States)

Dahm, Kevin; Newell, James

2001-01-01

Reports on a course at Rowan University, based on the economic design of a baseball stadium, that offers an introduction to multidisciplinary engineering design linked with formal training in technical communication. Addresses four pedagogical goals: (1) developing public speaking skills in a realistic, business setting; (2) giving students…

"School Shooter" Web Video Game Raises Concerns

Science.gov (United States)

Rhen, Brad

2011-01-01

A new video game in which the player stalks and shoots fellow students and teachers in school settings is drawing fire from school district officials. "School Shooter: North American Tour 2012" is a first-person game that allows the player to move around a school and collect points by killing defenseless students and teachers. The game,…

Introducing Player-Driven Video Analysis to Enhance Reflective Soccer Practice

DEFF Research Database (Denmark)

Hjort, Anders; Elbæk, Lars; Henriksen, Kristoffer

2017-01-01

. The implementation and evaluation of PU took place in the FC Copenhagen (FCK) School of Excellence. Findings show that PU can improve youth football players’ reflection skills through consistent video analyses and tagging, that coaches are important as role models and providers of feedback, and that the use......In the present study, we investigated the introduction of a cloud-based video analysis platform called Player Universe (PU) in a Danish football club. Video analysis is not a new performance-enhancing element in sport, but PU is innovative in the way players and coaches produce footage and how...... it facilitates reflective learning. Video analysis is executed in the (PU) platform by involving the players in the analysis process, in the sense that they are encouraged to tag game actions in video-documented football matches. Following this, players can get virtual feedback from their coach. The philosophy...

DoD Science and Engineering Apprenticeship Program for High School Students, 1996-󈨥 Activities

Science.gov (United States)

1997-05-01

Science Fair, A Honor Roll Baseball, Cross Country, Athletics, Weightlifting , Computers Robert Sidney Cox, III Other Male Leon High School...Sports Medicine Honor Roll Weightlifting , Swimming Marcus Mills Black Male Godby High School Florida State University Undecided FSU Incentive...paid for by the program. Seven of the students took a Psy- chology course, one a Nutritional Science class and two a Mathematics course. Eight of these

Frozen ammonia micropellet generator for Baseball II-T

International Nuclear Information System (INIS)

Denhoy, B.S.

1975-01-01

A ''startup'' plasma at the center of the Baseball II-T magnet was studied. This startup plasma will be used as a target for high energy neutral beams to achieve the required build-up. The target plasma will be created by irradiating a solid pellet with a laser beam. Although a deuterium pellet would be superior because of purity, the development of an ammonia pellet was undertaken because it requires a simpler technology. The ammonia target plasma is physically acceptable for the initial experiment. A frozen ammonia pellet, about 100 μm in diameter, will be irradiated with 300-J CO 2 laser, to produce a density of about 10 13 cm -3 and about 1 kV temperature

Return to competition, re-injury, and impact on performance of preseason shoulder injuries in Major League Baseball pitchers.

Science.gov (United States)

Makhni, Eric C; Lee, Randall W; Nwosu, Ekene O; Steinhaus, Michael E; Ahmad, Christopher S

2015-07-01

Major league baseball (MLB) pitchers are vulnerable to overuse injury of the upper extremity, especially in the shoulder. Injuries sustained in the preseason may have negative impact on performance following return. The goal of this study was to document the frequency of preseason shoulder injury in these athletes, as well as risk for re-injury and impact on performance following return from injury. A comprehensive search of MLB injury information from 2001 to 2010 of public databases yielded a cohort of MLB pitchers who sustained preseason shoulder injuries. These databases were utilized to obtain information regarding return to MLB competition, re-injury, and performance following return from injury. All performance metrics were compared to those of an age-matched control cohort. A total of 74 pitchers were identified who sustained a preseason shoulder injury. Only 39 (53%) returned that same season to pitch in the MLB competition. Of those that returned, nearly 50% of players were re-designated on the Disabled List during the return season. There was a decline in performance in earned run average and batting average against in the year of return. Compared to age-matched control pitchers, those with preseason shoulder injury had lower performance metrics across a number of outcomes. Preseason shoulder injury in MLB pitchers has the potential to result in high re-injury rates and decreased subsequent performance.

The NBA’s Maximum Player Salary and the Distribution of Player Rents

Directory of Open Access Journals (Sweden)

Kelly M. Hastings

2015-03-01

Full Text Available The NBA’s 1999 Collective Bargaining Agreement (CBA included provisions capping individual player pay in addition to team payrolls. This study examines the effect the NBA’s maximum player salary on player rents by comparing player pay from the 1997–1998 and 2003–2004 seasons while controlling for player productivity and other factors related to player pay. The results indicate a large increase in the pay received by teams’ second highest and, to a lesser extent, third highest paid players. We interpret this result as evidence that the adoption of the maximum player salary shifted rents from stars to complementary players. We also show that the 1999 CBA’s rookie contract provisions reduced salaries of early career players.

Do stingers affect scapular kinematics in rugby players?

Science.gov (United States)

Kawasaki, Takayuki; Maki, Nobukazu; Shimizu, Kyoko; Ota, Chihiro; Urayama, Shingo; Moriya, Shuichi; Kaketa, Takefumi; Kobayashi, Hideo; Kaneko, Kazuo

2014-12-01

Scapular dyskinesis is observed in subjects with pathologic conditions of the shoulder; however, there is limited information about the factors related to scapular dyskinesis among participants in rugby. The purpose of this study was to investigate the incidence, reliability, and relationships between scapular dyskinesis and variables related to the shoulder in high-school rugby players. A total of 164 Japanese high-school rugby players were evaluated with questionnaires, physical examinations, and a video analysis during their preseason. After evaluation of the inter-rater reliability of a classification of scapular dyskinesis, the outcomes were analyzed to assess the relationships between scapular dyskinesis and other variables during the preseason. The data were assessed with a logistic regression analysis calculating the odds ratios (OR). The inter-rater reliability among 3 blinded observers based on the Fleiss κ value and percentage agreement was .52 and 79.0%, respectively, which indicates that the method is moderately reliable. Scapular dyskinesis was identified in 16 (10.1%) shoulders among 159 players, with type I being prominent. A multivariate logistic regression analysis revealed that a type I dyskinesis was significantly associated with a past history of stingers with projected pain to the affected side of the shoulder (OR, 3.7) and the player's competitive grade at the time of the survey (OR, 3.9). Scapular dyskinesis is significantly associated with a past history of stingers. This suggests that stingers are a causative factor of scapular dyskinesis in the rugby population. Our method of evaluating scapular dyskinesis in collision athletes exhibits moderate reliability. Copyright © 2014 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Ballplayer or barrier breaker? Branding through the seven statues of Jackie Robinson

OpenAIRE

Stride, C.; Thomas, F.; Smith, M.M.

2014-01-01

Jackie Robinson is the baseball player most frequently depicted by a public statue within the USA, a ubiquity explained by his unique position as barrier breaker of the Major League colour bar. Utilising a detailed inspection of statue designs, locations and inscriptions, and comparisons with wider baseball statuary, Robinson's monuments reveal a distinctive set of cultural projections. These are commemorations distinguished by their age, location away from MLB ballparks, lack of action poses...

Path Analysis Examining Self-Efficacy and Decision-Making Performance on a Simulated Baseball Task

Science.gov (United States)

Hepler, Teri J.; Feltz, Deborah L.

2012-01-01

The purpose of this study was to examine the relationship between decision-making self-efficacy and decision-making performance in sport. Undergraduate students (N = 78) performed 10 trials of a decision-making task in baseball. Self-efficacy was measured before performing each trial. Decision-making performance was assessed by decision speed and…

Double-Play: Using Minor League Baseball to Apply Themes and Standards in Human Geography Courses

Science.gov (United States)

Zeitler, Ezra

2013-01-01

Growing student interest in sports provides geography teachers with a special opportunity to make connections between it and fundamental concepts in the discipline. This article examines the structure, arrangement, relationships, and distinctions among minor league baseball franchise locations, stadia, and team names, and presents examples of…

Instrumented mouthguard acceleration analyses for head impacts in amateur rugby union players over a season of matches.

Science.gov (United States)

King, Doug; Hume, Patria A; Brughelli, Matt; Gissane, Conor

2015-03-01

Direct impacts with the head (linear acceleration or pressure) and inertial loading of the head (rotational acceleration or strain) have been postulated as the 2 major mechanisms of head-related injuries such as concussion. Although data are accumulating for soccer and American football, there are no published data for nonhelmeted collision sports such as rugby union. To quantify head impacts via instrumented mouthguard acceleration analyses for rugby union players over a season of matches. Descriptive epidemiology study. Data on impact magnitude and frequency were collected with molded instrumented mouthguards worn by 38 premier amateur senior rugby players participating in the 2013 domestic season of matches. A total of 20,687 impacts >10g (range, 10.0-164.9g) were recorded over the duration of the study. The mean ± SD number of impacts per player over the duration of the season of matches was 564 ± 618, resulting in a mean ± SD of 95 ± 133 impacts to the head per player, per match over the duration of the season of matches. The impact magnitudes for linear accelerations were skewed to the lower values (Sp = 3.7 ± 0.02; P rugby union players over a season of matches, measured via instrumented mouthguard accelerations, were higher than for most sports previously reported. Mean linear acceleration measured over a season of matches was similar to the mean linear accelerations previously reported for youth, high school, and collegiate American football players but lower than that for female youth soccer players. Mean rotational acceleration measured over a season of matches was similar to mean rotational accelerations for youth, high school, and collegiate American football players but less than those for female youth soccer players, concussed American collegiate players, collegiate American football players, and professional American football players. © 2014 The Author(s).

Player-Character Dynamics in Multi- Player Role Playing Games

DEFF Research Database (Denmark)

Tychsen, Anders; McIlwain, D.; Brolund, T.

2007-01-01

This paper presents the results of a comprehensive empirical study of the impact of integrating complex game characters in multi-player Role Playing Games across tabletop and digital formats. Players were provided with characters that had detailed background history, personality and goals. Player...

Health Promotion at the Ballpark.

Science.gov (United States)

Hodges, Bonni C

2017-03-01

The arrival of a new summer collegiate baseball league franchise to a small central New York city was seen as an opportunity for health promotion. The initiative was set up to explore two overarching questions: (1) Are summer collegiate baseball events acceptable to local public health organizations as viable places for health promotion activities addressing local health issues? (2) Are summer collegiate baseball organizations amenable to health promotion activities built in to their fan and/or player experiences? Planning and implementation were guided by precede-proceed, social cognitive theory, social marketing, and diffusion of innovations constructs. Environmental changes were implemented to support healthy eating and nontobacco use by players and fans; four health awareness nights were implemented at home games corresponding to local public health priorities and included public service announcements, between inning quizzes, information dissemination at concession and team market locations, and special guests. Sales and fan feedback support mostly healthy concession offerings and a tobacco-free ballpark; postseason evaluations from team staff and public health partners support continuing the trials of this sports event as a venue for health promotion.

Applying Multiculturalism to a High School American Literature Course: Changing Lenses and Crossing Borders.

Science.gov (United States)

Noskin, David; Marshalek, Angela

1995-01-01

Describes a nine-week, secondary-school, language arts unit on the American dream with an emphasis on multicultural issues, particularly as they concern those students who are apathetic about or resistant to the multicultural program. Reviews specific lesson approaches to "The Great Gatsby,""Baseball in April,""Justin and…

76 FR 37007 - Safety Zone; Stockton Ports Baseball Club Fourth of July Fireworks Display, Stockton, CA

Science.gov (United States)

2011-06-24

..., performance, design, or operation; test methods; sampling procedures; and related management systems practices...-AA00 Safety Zone; Stockton Ports Baseball Club Fourth of July Fireworks Display, Stockton, CA AGENCY... inspection or copying two locations: the Docket Management Facility (M-30), U.S. Department of Transportation...

METRIC TESTS CHARACTERISTIC FOR ESTIMATING JUMPING FOR VOLLEYBALL PLAYERS

Directory of Open Access Journals (Sweden)

Toplica Stojanović

2008-08-01

Full Text Available With goal to establish metric tests characteristics for estimating jumping for volleyball players, it was organized a pilot research on pattern of 23 volleyball players from cadet team and 23 students from high-school. For needs of this research four tests are valid for estimation, jump in block with left and right leg and jump in spike with left and right leg. Each test has been taken three times, so that we could with test-re test method determine their reliability, and with factor analysis their validity. Data were processed by multivariate analysis (item analysis, factor analysis from statistical package „Statistica 6.0 for windows“. On the results of research and discussion we can say that the tests had high coefficient of reliability, as well as factor validity, and these tests can be used to estimate jumping for volleyball players.

Factors Related to the Academic Success and Failure of College Football Players: The Case of the Mental Dropout.

Science.gov (United States)

Lang, Gale; And Others

1988-01-01

Examines variables used to predict the academic success or failure of college football players. Valid predictors include the following: (1) high school grades; (2) repeating a year in school; (3) feelings towards school; (4) discipline history; (5) mother's education; and (6) high school background. (FMW)

Video incident analysis of concussions in boys' high school lacrosse.

Science.gov (United States)

Lincoln, Andrew E; Caswell, Shane V; Almquist, Jon L; Dunn, Reginald E; Hinton, Richard Y

2013-04-01

Boys' lacrosse has one of the highest rates of concussion among boys' high school sports. A thorough understanding of injury mechanisms and game situations associated with concussions in boys' high school lacrosse is necessary to target injury prevention efforts. To characterize common game-play scenarios and mechanisms of injury associated with concussions in boys' high school lacrosse using game video. Descriptive epidemiological study. In 25 public high schools of a single school system, 518 boys' lacrosse games were videotaped by trained videographers during the 2008 and 2009 seasons. Video of concussion incidents was examined to identify game characteristics and injury mechanisms using a lacrosse-specific coding instrument. A total of 34 concussions were captured on video. All concussions resulted from player-to-player bodily contact. Players were most often injured when contact was unanticipated or players were defenseless (n = 19; 56%), attempting to pick up a loose ball (n = 16; 47%), and/or ball handling (n = 14; 41%). Most frequently, the striking player's head (n = 27; 79%) was involved in the collision, and the struck player's head was the initial point of impact in 20 incidents (59%). In 68% (n = 23) of cases, a subsequent impact with the playing surface occurred immediately after the initial impact. A penalty was called in 26% (n = 9) of collisions. Player-to-player contact was the mechanism for all concussions. Most commonly, injured players were unaware of the pending contact, and the striking player used his head to initiate contact. Further investigation of preventive measures such as education of coaches and officials and enforcement of rules designed to prevent intentional head-to-head contact is warranted to reduce the incidence of concussions in boys' lacrosse.

Thermoregulation, Fluid Balance, and Sweat Losses in American Football Players.

Science.gov (United States)

Davis, Jon K; Baker, Lindsay B; Barnes, Kelly; Ungaro, Corey; Stofan, John

2016-10-01

studies in different geographical regions (i.e., southeast) of the United States. Further, there have been a limited number of studies examining body core temperature of American Football players during preseason practice, especially at the high school level. Future field-based research in American Football with various levels of competition in hotter geographical regions of the United States is warranted.

Impact of specific training and competition on myocardial structure and function in different age ranges of male handball players.

Directory of Open Access Journals (Sweden)

Brahim Agrebi

Full Text Available Handball activity involves cardiac changes and demands a mixture of both eccentric and concentric remodeling within the heart. This study seeks to explore heart performance and cardiac remodeling likely to define cardiac parameters which influence specific performance in male handball players across different age ranges. Forty three players, with a regular training and competitive background in handball separated into three groups aged on average 11.78 ± 0.41 for youth players aka "schools", "elite juniors" 15.99 ± 0.81 and "elite adults" 24.46 ± 2.63 years, underwent echocardiography and ECG examinations. Incremental ergocycle and specific field (SFT tests have also been conducted. With age and regular training and competition, myocardial remodeling in different age ranges exhibit significant differences in dilatation's parameters between "schools" and "juniors" players, such as the end-diastolic diameter (LVEDD and the end-systolic diameter of the left ventricle (LVESD, the root of aorta (Ao and left atrial (LA, while significant increase is observed between "juniors" and "adults" players in the interventricular septum (IVS, the posterior wall thicknesses (PWT and LV mass index. ECG changes are also noted but NS differences were observed in studied parameters. For incremental maximal test, players demonstrate a significant increase in duration and total work between "schools" and "juniors" and, in total work only, between "juniors" and "seniors". The SFT shows improvement in performance which ranged between 26.17 ± 1.83 sec to 31.23 ± 2.34 sec respectively from "seniors" to "schools". The cross-sectional approach used to compare groups with prior hypothesis that there would be differences in exercise performance and cardiac parameters depending on duration of prior handball practice, leads to point out the early cardiac remodeling within the heart as adaptive change. Prevalence of cardiac chamber dilation with less hypertrophy remodeling

Impact of specific training and competition on myocardial structure and function in different age ranges of male handball players.

Science.gov (United States)

Agrebi, Brahim; Tkatchuk, Vladimir; Hlila, Nawel; Mouelhi, Emna; Belhani, Ali

2015-01-01

Handball activity involves cardiac changes and demands a mixture of both eccentric and concentric remodeling within the heart. This study seeks to explore heart performance and cardiac remodeling likely to define cardiac parameters which influence specific performance in male handball players across different age ranges. Forty three players, with a regular training and competitive background in handball separated into three groups aged on average 11.78 ± 0.41 for youth players aka "schools", "elite juniors" 15.99 ± 0.81 and "elite adults" 24.46 ± 2.63 years, underwent echocardiography and ECG examinations. Incremental ergocycle and specific field (SFT) tests have also been conducted. With age and regular training and competition, myocardial remodeling in different age ranges exhibit significant differences in dilatation's parameters between "schools" and "juniors" players, such as the end-diastolic diameter (LVEDD) and the end-systolic diameter of the left ventricle (LVESD), the root of aorta (Ao) and left atrial (LA), while significant increase is observed between "juniors" and "adults" players in the interventricular septum (IVS), the posterior wall thicknesses (PWT) and LV mass index. ECG changes are also noted but NS differences were observed in studied parameters. For incremental maximal test, players demonstrate a significant increase in duration and total work between "schools" and "juniors" and, in total work only, between "juniors" and "seniors". The SFT shows improvement in performance which ranged between 26.17 ± 1.83 sec to 31.23 ± 2.34 sec respectively from "seniors" to "schools". The cross-sectional approach used to compare groups with prior hypothesis that there would be differences in exercise performance and cardiac parameters depending on duration of prior handball practice, leads to point out the early cardiac remodeling within the heart as adaptive change. Prevalence of cardiac chamber dilation with less hypertrophy remodeling was found

The Anthropometric Characteristics of Futsal Players Compared with Professional Soccer Players

Directory of Open Access Journals (Sweden)

Burdukiewicz Anna

2014-08-01

Full Text Available Purpose. The aim of the study was to compare the morphological characteristics of experienced futsal players with professional soccer players. Methods. The research sample included 22 university futsal players and 22 professional soccer players. Parameters including body height and mass, skinfold thicknesses of the trunk and extremities, lower limb length, trunk width, humerus and femur bone breadths, and the circumferences of the chest, hips, thighs, and calves were used to calculate various somatic indices. Somatotyping was performed using the Heath–carter method. Differences in the characteristics between the futsal and soccer players were analyzed using Student’s t test. Intragroup analysis was also performed on futsal players depending on player position and compared with the arithmetic means and standard deviations of all variables of the entire sample. Results. compared with their soccer-playing peers, the futsal players were shorter, weighed less, had shorter lower limbs, narrower hips, and smaller hip circumference and bone breadth values. In contrast, higher levels of body fat and endomorphy were noted in this group. The proportion of mesomorphs and ectomorphs were similar in both groups. Futsal goalkeepers were differentiated by greater subcutaneous adiposity and body mass. Defenders had the slimmest body shape, with relatively narrower shoulders and hips, smaller bone breadths, and lower levels of adiposity. The body build of wingers was slightly larger. Pivoters were characterized by greater body height and larger values for the characteristics measuring the lateral trunk dimensions. Conclusions. The observed morphological differences between futsal and soccer players were mainly in body height and height-associated characteristics. This indicates that no specialized approach in futsal recruitment is currently used. This points to the need to develop a specialized approach in the player recruitment stage, as the tactical and

Measurement of fatigue in knee flexor and extensor muscles.

Science.gov (United States)

Kawabata, Y; Senda, M; Oka, T; Yagata, Y; Takahara, Y; Nagashima, H; Inoue, H

2000-04-01

In order to examine fatigue of the knee flexor and extensor muscles and to investigate the characteristics of muscular fatigue in different sports, a Cybex machine was used to measure muscle fatigue and recovery during isokinetic knee flexion and extension. Eighteen baseball players, 12 soccer players and 13 marathon runners were studied. Each subject was tested in the sitting position and made to perform 50 consecutive right knee bends and stretches at maximum strength. This was done 3 times with an interval of 10 min between each series. The peak torque to body weight ratio and the fatigue rate were determined in each case. In all subjects, the peak torque to body weight ratio was higher for extensors than flexors. Over the 3 trials, the fatigue rate of extensors showed little change, while that of flexors had a tendency to increase. In each subject, knee extensors showed a high fatigue rate but a quick recovery, while knee flexors showed a low fatigue rate but a slow recovery. As the marathon runners had the smallest fatigue rates for both flexors and extensors, we concluded that marathon runners had more stamina than baseball players and soccer players.

Prediction of Lateral Ankle Sprains in Football Players Based on Clinical Tests and Body Mass Index.

Science.gov (United States)

Gribble, Phillip A; Terada, Masafumi; Beard, Megan Q; Kosik, Kyle B; Lepley, Adam S; McCann, Ryan S; Pietrosimone, Brian G; Thomas, Abbey C

2016-02-01

The lateral ankle sprain (LAS) is the most common injury suffered in sports, especially in football. While suggested in some studies, a predictive role of clinical tests for LAS has not been established. To determine which clinical tests, focused on potentially modifiable factors of movement patterns and body mass index (BMI), could best demonstrate risk of LAS among high school and collegiate football players. Case-control study; Level of evidence, 3. A total of 539 high school and collegiate football players were evaluated during the preseason with the Star Excursion Balance Test (SEBT) and Functional Movement Screen as well as BMI. Results were compared between players who did and did not suffer an LAS during the season. Logistic regression analyses and calculated odds ratios were used to determine which measures predicted risk of LAS. The LAS group performed worse on the SEBT-anterior reaching direction (SEBT-ANT) and had higher BMI as compared with the noninjured group (P football players. BMI was also significantly higher in football players who sustained an LAS. Identifying clinical tools for successful LAS injury risk prediction will be a critical step toward the creation of effective prevention programs to reduce risk of sustaining an LAS during participation in football. © 2015 The Author(s).

Comparison of Some Biomotoric Properties and Anthropometric Measurements of Male Basketball and Football Players

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Turna, Bülent; Kilinç, Fatih

2018-01-01

The purpose of this study is to determine and compare some biomotoric properties and anthropometric measurements of Antalya Muratpasa High School Boys' Basketball Team and Football Team. Thirty volunteering players from Antalya Muratpasa High School Boys' Basketball and Football Teams participated in the study. Fifteen of the participants were…

FMRI hypoactivation during verbal learning and memory in former high school football players with multiple concussions.

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Terry, Douglas P; Adams, T Eric; Ferrara, Michael S; Miller, L Stephen

2015-06-01

Multiple concussions before the age of 18 may be associated with late-life memory deficits. This study examined neural activation associated with verbal encoding and memory retrieval in former athletes ages 40-65 who received at least two concussions (median = 3; range = 2-15) playing high school football and a group of former high school football players with no reported history of concussions matched on age, education, and pre-morbid IQ. Functional magnetic resonance imaging data collected during a modified verbal paired associates paradigm indicated that those with concussive histories had hypoactivation in left hemispheric language regions, including the inferior/middle frontal gyri and angular gyrus compared with controls. However, concussive history was not associated with worse memory functioning on neuropsychological tests or worse behavioral performance during the paradigm, suggesting that multiple early-life concussions may be associated with subtle changes in the verbal encoding system that limits one from accessing higher-order semantic networks, but this difference does not translate into measurable cognitive performance deficits. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Prospective Player-Reported Injuries in Female Youth Fast-Pitch Softball Players.

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Smith, Matthew V; Davis, Randi; Brophy, Robert H; Prather, Heidi; Garbutt, Jane; Wright, Rick W

2015-01-01

There is a scarcity of literature evaluating injuries in youth fast-pitch softball players. To perform a descriptive analysis of player-reported injuries in youth fast-pitch softball position players and pitchers during a single select-level season. Prospective observation cohort study. Level 3. Ninety-eight athletes (48 pitchers, 50 position players) were followed for a single select fast-pitch softball season. Study participants completed web-based surveys every 3 weeks reporting injuries related to participation in fast-pitch softball. Injury was defined as pain causing cessation of participation in the current game or practice that prevents the player's return to that session or any pain that causes cessation of a player's customary participation on the day after the day of onset. The median age of the study participants was 14 years (range, 9-18 years). There were 49 reported injuries in 98 athletes. The average age was 13 years for those not injured and 14 years for those who were injured (P softball players. Better off-season and preseason conditioning may be a key factor for reducing pitching injuries. Recognition of injury patterns in fast-pitch softball players is critical to developing strategies to keep these athletes competing safely. © 2015 The Author(s).

Equal Opportunity Employers: The Department of Defense and Major League Baseball

Science.gov (United States)

1993-01-01

indication of the black athlete’s presence in American sports: Of the more than 1,300 players in the NFL, about 60 percent are Black. In the NBA , black...enabled today’s successes to manifest themselves. The Nearo Leacue Although, black players were forbidden from playing within the white league, this...actuality as opposing player had spit in his face. ’I don’t know any other player that could have gone through2 what he did and been successful

Biomechanical differences in female basketball and soccer players during multi-directional jump landings.

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Taylor, Jeffrey B; Ford, Kevin R; Schmitz, Randy J; Ross, Scott E; Ackerman, Terry A; Shultz, Sandra J

2017-07-14

Anterior cruciate ligament injury prevention programs are less successful in basketball than soccer and may be due to distinct movement strategies that these athletes develop from sport-specific training. The purpose of this study was to identify biomechanical differences between female basketball and soccer players during multi-directional jump landings. Lower extremity biomechanics of eighty-nine female athletes who played competitive basketball (n=40) or soccer (n=49) at the middle- or high-school level were analyzed with three-dimensional motion analysis during a drop vertical jump (DVJ), double- (SAG-DL) and single-leg forward jump (SAG-SL), and double- (FRONT-DL) and single-leg (FRONT-SL) lateral jump. Basketball players landed with less hip and/or knee excursion during all tasks (pbasketball players landed with greater peak hip flexion angles (p=.04). The FRONT-SL task elicited the most distinct sport-specific differences, including decreased hip adduction (pbasketball players. Additionally, the FRONT-SL task elicited greater forces in knee abduction (p=.003) and lesser forces in hip adduction (p=.001) and knee external rotation (pbasketball players. Joint energetics were different during the FRONT-DL task, as basketball players exhibited less sagittal plane energy absorption at the hip (pjump landing tasks, such that soccer players exhibited a more protective landing strategy than basketball players, justifying future efforts toward sport-specific ACL injury prevention programs.

Sports Adaptations for Unilateral and Bilateral Upper-Limb Amputees: Archery/Badminton/Baseball/Softball/Bowling/Golf/Table Tennis.

Science.gov (United States)

Cowart, Jim

1979-01-01

The booklet discusses sports adaptations for unilateral and bilateral upper limb amputees. Designs for adapted equipment are illustrated and information on adaptations are described for archery (including an archery release aid and a stationary bow holder); badminton (serving tray); baseball/softball (adaptations for catching, throwing, and…

Relationship of biomechanical factors to baseball pitching velocity: within pitcher variation.

Science.gov (United States)

Stodden, David F; Fleisig, Glenn S; McLean, Scott P; Andrews, James R

2005-02-01

To reach the level of elite, most baseball pitchers need to consistently produce high ball velocity but avoid high joint loads at the shoulder and elbow that may lead to injury. This study examined the relationship between fastball velocity and variations in throwing mechanics within 19 baseball pitchers who were analyzed via 3-D high-speed motion analysis. Inclusion in the study required each one to demonstrate a variation in velocity of at least 1.8 m/s (range 1.8-3.5 m/s) during 6 to 10 fastball pitch trials. Three mixed model analyses were performed to assess the independent effects of 7 kinetic, 11 temporal, and 12 kinematic parameters on pitched ball velocity. Results indicated that elbow flexion torque, shoulder proximal force, and elbow proximal force were the only three kinetic parameters significantly associated with increased ball velocity. Two temporal parameters (increased time to max shoulder horizontal adduction and decreased time to max shoulder internal rotation) and three kinematic parameters (decreased shoulder horizontal adduction at foot contact, decreased shoulder abduction during acceleration, and increased trunk tilt forward at release) were significantly related to increased ball velocity. These results point to variations in an individual's throwing mechanics that relate to pitched ball velocity, and also suggest that pitchers should focus on consistent mechanics to produce consistently high fastball velocities. In addition, pitchers should strengthen shoulder and elbow musculature that resist distraction as well as improve trunk strength and flexibility to maximize pitching velocity and help prevent injury.

Injuries in Australian school-level rugby union.

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Leung, Felix T; Franettovich Smith, Melinda M; Hides, Julie A

2017-11-01

There is a high incidence of injuries in rugby union due to the physical nature of the game. In youth rugby union, there are large variations in injury rates reported. Our study investigated the rates of injuries in school-level rugby union players in Australia using the consensus statement for rugby union injuries. Injury surveillance was conducted on 480 rugby players from 1 school in Queensland, Australia. Injury data were collected using paper-based injury recording forms during the 8-week rugby season using a "medical-attention" injury definition. In total, 76 players sustained one or more injuries, with a total of 80 injuries recorded. The overall injury rate was 31.8 injuries/1000 match player hours (95% CI, 25.4-39.4). Concussion had an incidence rate of 6.0/1000 match player hours (95% CI, 3.5-9.6). The incidence of upper limb and lower limb injuries were 9.1 and 9.9/1000 match player hours, respectively (95% CI, 5.9-13.5 and 6.6-14.5). The older age divisions had higher injury rates and most injuries occurred while tackling or being tackled. The injury rates observed in this sample of Australian school rugby union players provides direction for future studies to enable informed decisions relating to development of injury prevention programmes at this level of rugby.

Academic characteristics of orthopedic team physicians affiliated with high school, collegiate, and professional teams.

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Makhni, Eric C; Buza, John A; Byram, Ian; Ahmad, Christopher S

2015-11-01

We conducted a study to determine the academic involvement and research productivity of orthopedic team physicians at high school, college, and professional levels of sport. Through Internet and telephone queries, we identified 1054 team physicians from 362 institutions, including 120 randomly selected high schools and colleges and 122 professional teams (baseball, basketball, football, hockey). For all physicians included in the study, we performed a comprehensive search of the Internet and of a citation database to determine academic affiliations, number of publications, and h-index values. Of the 1054 physicians, 678 (64%) were orthopedic surgeons. Percentage of orthopedic team physicians affiliated with an academic medical center was highest in professional sports (64%; 173/270) followed by collegiate sports (36%; 98/275) and high school sports (20%; 27/133). Median number of publications per orthopedic team physician was significantly higher in professional sports (30.6) than in collegiate sports (10.7) or high school sports (6). Median number of publications by orthopedic physicians also varied by sport, with the highest number in Major League Baseball (37.9; range, 0-225) followed by the National Basketball Association (32.0; range, 0-227) and the National Football League (30.4; range, 0-460), with the lowest number within the National Hockey League (20.7; range, 0-144). Academic affiliation and research productivity of orthopedic team physicians vary by competition level and professional sporting league.

A Mathematical Modelling Approach to One-Day Cricket Batting Orders

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Bukiet, Bruce; Ovens, Matthews

2006-01-01

While scoring strategies and player performance in cricket have been studied, there has been little published work about the influence of batting order with respect to One-Day cricket. We apply a mathematical modelling approach to compute efficiently the expected performance (runs distribution) of a cricket batting order in an innings. Among other applications, our method enables one to solve for the probability of one team beating another or to find the optimal batting order for a set of 11 players. The influence of defence and bowling ability can be taken into account in a straightforward manner. In this presentation, we outline how we develop our Markov Chain approach to studying the progress of runs for a batting order of non- identical players along the lines of work in baseball modelling by Bukiet et al., 1997. We describe the issues that arise in applying such methods to cricket, discuss ideas for addressing these difficulties and note limitations on modelling batting order for One-Day cricket. By performing our analysis on a selected subset of the possible batting orders, we apply the model to quantify the influence of batting order in a game of One Day cricket using available real-world data for current players. Key Points Batting order does effect the expected runs distribution in one-day cricket. One-day cricket has fewer data points than baseball, thus extreme values have greater effect on estimated probabilities. Dismissals rare and probabilities very small by comparison to baseball. Probability distribution for lower order batsmen is potentially skewed due to increased risk taking. Full enumeration of all possible line-ups is impractical using a single average computer. PMID:24357943

Private Financing and Sports Franchise Values: The Case of Major League Baseball

OpenAIRE

Phillip Miller

2006-01-01

This paper examines the impact of receiving a new stadium on team franchise values. I argue that a new stadium will increase the franchise values of teams regardless of how construction was financed. A team playing in a stadium that it owns will be able to capitalize the value of the stadium in the team’s franchise value and will thus have a higher franchise value. Using panel data for Major League Baseball teams from 1990-2002, I find that, after controlling for team quality and metro area d...

[Anthropometrical profile of Brazilian junior volleyball players for different sports requirement levels].

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Fonseca-Toledo, Cláudio; Roquetti, Paula; Fernandes-Filho, José

2010-12-01

This study was aimed at investigating the anthropometrics characteristics of male Brazilian junior volleyball players, organised into 3 sports requirement groups: high qualification (HQ) formed by the national team, middle qualification (MQ) formed by athletes playing in the Brazilian national championships and low qualification (LQ) formed by players at school level. 101 athletes were observed, HQ (n=16), MQ (n=68) and LQ (n=17), aged 16.7 ± 0.5; 16.6 ± 0.5 and 16.2 ± 0.7 years, respectively. There following were evaluated: body mass, height, standing reach height, % body fat and Heath & Carter somatotype. The statistical analysis was descriptive and inferential, the Kruskal Wallis test being used for detecting differences between groups (pcharacteristics and requirement levels, considering psports' selection instrument for young talented volleyball players.

Laser startup optics for Baseball II and future mirror machines

International Nuclear Information System (INIS)

Frank, A.M.; Chargin, A.K.; Brown, N.J.

1975-01-01

The laser startup system for Baseball II-T uses a 300-J CO 2 laser to hit a 100-μ diameter pellet with a laser power density on the order of 10 13 W/cm 2 . The laser is a 20-cm diameter unstable resonator transversely excited (TEA) oscillator. The beam is split and then focused using off-axis parabolas. The symmetric configuration and central obscuration of the CO 2 beam allow coaxial alignment and pellet detection optics. This experiment primarily uses commercially available systems and components. Optical elements were fabricated both by direct machining and standard polishing techniques. The laser and optical systems are directly scalable to reactor requirements using demonstrated technologies

Epidemiology of soccer-related injuries among male high school ...

African Journals Online (AJOL)

Soccer in Rwandan high schools can expose players to the risk of injury warranting prevention programmes. The aim of this study was to determine the type, causes, severity and management of injuries among high school soccer players in Rwanda, in order to obtain baseline data for injury prevention programmes.

Recognizing and managing concussion in school sport.

Science.gov (United States)

Evans, Vicki

2014-08-01

Every country around the world enjoys some sort of sport. The Olympics sees countries from all over the globe participate in elite sport, in both winter and summer competitions. Australia is widely known for cricket and rugby; America is known for baseball and gridiron football (among others). These sports are played at an elite level as well as beginners from early ages as young as 4 years in the backyard. Yet, it is also these sports that can deliver a ball at the speed of 100 km/h (football), 105 km/h (baseball), 112 km/h (rugby), 150 km/h (cricket), and 211 km/h (soccer). This is the same force that a car collision can produce. That force eventually finds a target, and in some cases, unfortunately, it is a head. Damage to the brain is not only from the impact of the ball hitting its target but rather also the shearing forces of acceleration-deceleration injury that can cause extensive injuries. There has been much discussion of late regarding concussion in sport and the accumulative effects of head blows resulting in varying degrees of memory loss and dementia later in life. The media have been saturated with heightened awareness of chronic traumatic encephalopathy. This, however, is still being researched. It is true that each concussion compounds the one before, but rather than focus on the injury, managers/coaches and sporting codes should be focusing on the identification and proper management of a suspected concussion and the return-to-play protocols. This is especially important in our schools where growing brains need nurturing. Neuroscience nurses are at the forefront of educating school children, teachers, and coaches through partnering with local schools. This article will focus on concussion recognition and management in school sport.

A prospective cohort study identifying risk factors for shoulder injuries in adolescent elite handball players: the Karolinska Handball Study (KHAST) study protocol.

Science.gov (United States)

Asker, Martin; Waldén, Markus; Källberg, Henrik; Holm, Lena W; Skillgate, Eva

2017-11-22

Handball is a physical contact sport that includes frequent overhead throwing, and this combination leads to a high rate of shoulder injuries. Several factors have been associated with shoulder injuries in overhead athletes, but strong scientific evidence is lacking for most suggested risk factors. We therefore designed the Karolinska Handball Study (KHAST) with the aim to identify risk factors for shoulder injuries in adolescent male and female elite handball players studying at handball-profiled secondary schools in Sweden. Secondary objectives are to investigate whether shoulder function changes during the competition season and whether the physical profile of the players changes during their time in secondary school. Players aged 15 to 19 years were included during the pre-season period of the 2014-2015 and the 2015-2016 seasons. At inclusion, players signed informed consent and filled in a questionnaire regarding playing position, playing level, previous handball experience, history of shoulder problems and athletic identity. Players also completed a detailed test battery at baseline evaluating the shoulder, neck and trunk. Players were then prospectively monitored weekly during the 2014-2015 and/or 2015-2016 competitive seasons regarding injuries and training/match workload. Results from the annual routine physical tests in the secondary school curriculum including bench press, deep squat, hand grip strength, clean lifts, squat jumps, counter movement jumps, handball players and a reduction of these injuries is therefore warranted. However, in order to introduce appropriate preventive measures, a detailed understanding of the underlying risk factors is needed. Our study has a high potential to identify important risk factors for shoulder injuries in adolescent elite handball players owing to a large study sample, a high response rate, data collection during consecutive seasons, and recording of potential confounding factors.

Biomechanical Differences of Multidirectional Jump Landings Among Female Basketball and Soccer Players.

Science.gov (United States)

Taylor, Jeffrey B; Ford, Kevin R; Schmitz, Randy J; Ross, Scott E; Ackerman, Terry A; Shultz, Sandra J

2017-11-01

Taylor, JB, Ford, KR, Schmitz, RJ, Ross, SE, Ackerman, TA, and Shultz, SJ. Biomechanical differences of multidirectional jump landings among female basketball and soccer players. J Strength Cond Res 31(11): 3034-3045, 2017-Anterior cruciate ligament (ACL) injury prevention programs are less successful in basketball than soccer and may be due to distinct movement strategies that these athletes develop from sport-specific training. The purpose of this study was to identify biomechanical differences between female basketball and soccer players during multidirectional jump landings. Lower extremity biomechanics of 89 female athletes who played competitive basketball (n = 40) or soccer (n = 49) at the middle- or high-school level were analyzed with 3-dimensional motion analysis during a drop vertical jump, double- (SAG-DL) and single-leg forward jump (SAG-SL), and double- (FRONT-DL) and single-leg (FRONT-SL) lateral jump. Basketball players landed with either less hip or knee, or both hip and knee excursion during all tasks (p ≤ 0.05) except for the SAGSL task, basketball players landed with greater peak hip flexion angles (p = 0.04). The FRONT-SL task elicited the most distinct sport-specific differences, including decreased hip adduction (p soccer players exhibited a more protective landing strategy than basketball players, justifying future efforts toward sport-specific ACL injury prevention programs.

Racial Fault-lines in “Baseball’s Great Experiment:” Black Perceptions, White Reactions

Directory of Open Access Journals (Sweden)

Henry D. Fetter

2012-06-01

Full Text Available This paper examines three facets of the breaking of major league baseball’s color line by Jackie Robinson of the Brooklyn Dodgers in 1947: the perception of blacks, the response of white players (whether teammates or opponents, and the reaction of baseball fans. By so doing, the paper will illuminate the fault-lines that characterized race relations within both the sport of baseball and the larger society as each was confronted with new challenges to long established policies and practices in the years after the Second World War.

Physical Education for High School Students. A Book of Sports, Athletics, and Recreational Activities for Teen-Age Boys and Girls.

Science.gov (United States)

Savage, William H., Ed.

This book about physical activity was written especially for high school students. It is divided into chapters on different physical events. Among the activities discussed are archery, badminton, baseball and softball, golf, riflery, swimming, tennis, touch football, volleyball, and wrestling. Each chapter contains discussions of the history of…

Estimation of the adiabatic energy limit versus beta in Baseball II

International Nuclear Information System (INIS)

Foote, J.H.

1976-01-01

Several estimates of the adiabatic energy limit versus beta in Baseball II are summarized, and the calculational methods used to obtain them are described. Some estimates are based on analytic expressions; for others, particle orbits are calculated, magnetic-moment jumps are inspected, and adiabatic limits then derived. The results are sensitive to the assumed variation of the combined vacuum-plus-plasma magnetic field. The calculated adiabatic energy limit falls rapidly with beta, even for a gradual magnetic-field variation. If we assume a sharp depression in the axial profile of the combined magnetic field for a finite-beta plasma, the adiabatic limit can be further markedly reduced

Do cell phones, iPods/MP3 players, siblings and friends matter? Predictors of child body mass in a U.S. Southern Border City Middle School.

Science.gov (United States)

Ynalvez, Marcus Antonius; Ynalvez, Ruby; Torregosa, Marivic; Palacios, Horacio; Kilburn, John

2012-01-01

This study examines the association of children's (i) micro-social environment, specifically siblings [kin-friends] and friends from school and neighborhood [non-kin-friends], and (ii) ownership of information and communication technologies (ICT), specifically cell phones and iPod/MP3 players, with body mass index percentile (BMIp). Fifty-five randomly selected 6th graders with a mean age of 12 years, stratified by gender (23 boys and 32 girls), from a Texas middle school located in a city along the U.S. southern border. The linear regression of BMIp on number of siblings and of non-kin-friends, and ownership of cell phone and of iPod/MP3 player was examined using two models: M1 was based on the manual selection of predictors from a pool of potential predictors. M2 was derived from the predictors specified in M1 using backward elimination technique. Because sample size was small, the significance of regression coefficients was evaluated using robust standard errors to calculate t-values. Data for predictors were obtained through a survey. Height and weight were obtained through actual anthropometric measurements. BMIp was calculated using the on-line BMI calculator of the Center for Disease Control and Prevention. Findings reveal that children's social environment and ICT ownership predict BMIp; specifically, number of siblings (M2: β = -0.34, p-value MP3 players (M2: β = 0.33, p-value < .001). These results underscore the importance of family in configuring, and of new personal technical devices (that encourage solitary, and oftentimes sedentary, activities) in predicting child body mass. © 2012 Asian Oceanian Association for the Study of Obesity . Published by Elsevier Ltd. All rights reserved.

The Effectiveness Evaluation among Different Player-Matching Mechanisms in a Multi-Player Quiz Game

Science.gov (United States)

Tsai, Fu-Hsing

2016-01-01

This study aims to investigate whether different player-matching mechanisms in educational multi-player online games (MOGs) can affect students' learning performance, enjoyment perception and gaming behaviors. Based on the multi-player quiz game, TRIS-Q, developed by Tsai, Tsai and Lin (2015) using a free player-matching (FPM) mechanism, the same…

Frontal lobe function in chess players.

Science.gov (United States)

Nejati, Majid; Nejati, Vahid

2012-01-01

Chess is considered as a cognitive game because of severe engagement of the mental resources during playing. The purpose of this study is evaluation of frontal lobe function of chess players with matched non-players. Wisconsin Card Sorting Test (WCST) data showed no difference between the player and non-player groups in preservation error and completed categories but surprisingly showed significantly lower grade of the player group in correct response. Our data reveal that chess players don't have any preference in any stage of Stroop test. Chess players don't have any preference in selective attention, inhibition and executive cognitive function. Chess players' have lower shifting abilities than non-players.

Veto players

NARCIS (Netherlands)

Warntjen, Andreas; Dowding, Keith

2010-01-01

Veto players are political actors whose consent is necessary to adopt a new policy. Put otherwise, they have veto power which allows them to prevent a change to the status quo. The concept is crucial to the influential veto player theory developed by George Tsebelis. Building on earlier work in

Frontal Lobe Function in Chess Players

Directory of Open Access Journals (Sweden)

Vahid Nejati

2012-05-01

Full Text Available Chess is considered as a cognitive game because of severe engagement of the mental resources during playing. The purpose of this study is evaluation of frontal lobe function of chess players with matched non-players. Wisconsin Card Sorting Test (WCST data showed no difference between the player and non-player groups in preservation error and completed categories but surprisingly showed significantly lower grade of the player group in correct response. Our data reveal that chess players dont have any preference in any stage of Stroop test. Chess players dont have any preference in selective attention, inhibition and executive cognitive function. Chess players' have lower shifting abilities than non-players.

Target-plasma production by laser irradiation of a pellet in the Baseball II-T experiment

International Nuclear Information System (INIS)

Damm, C.C.; Foote, J.H.; Futch, A.H.; Goodman, R.K.; Hornady, R.S.; Osher, J.E.; Porter, G.D.

1977-01-01

One way to generate a plasma target that can be used in conjunction with an injected neutral beam to initiate a high-energy plasma in a steady-state, magnetic-mirror field is by the laser irradiation of a solid pellet located within the confinement region. In the Lawrence Livermore Laboratory Baseball II-T experiment, a CO 2 laser was used to provide a two-sided irradiation of an ammonia pellet; the maximum laser intensity on the pellet was approximately 4 x 10 12 W/cm 2 . The 150-μm-dia pellets were guided to the laser focal spot in the Baseball II-T magnetic field using steering voltages controlled by a microcomputer-based system. Diagnostics showed complete ionization of the pellet, average ion energies in the keV range, synchronized triggering of the laser and the neutral beam, and rapid expansion of the plasma to a diameter that was a good match to the diameter of the neutral beam. Predictions obtained from the LASNEX code compared well with measured results. Although the laser-pellet approach was proven usable as a target-plasma startup system, it would be much more complicated and expensive than the method in which streaming plasma is used to trap the neutal beams

Prospective Player-Reported Injuries in Female Youth Fast-Pitch Softball Players

Science.gov (United States)

Smith, Matthew V.; Davis, Randi; Brophy, Robert H.; Prather, Heidi; Garbutt, Jane; Wright, Rick W.

2015-01-01

Background: There is a scarcity of literature evaluating injuries in youth fast-pitch softball players. Purpose: To perform a descriptive analysis of player-reported injuries in youth fast-pitch softball position players and pitchers during a single select-level season. Study Design: Prospective observation cohort study. Level of Evidence: Level 3. Methods: Ninety-eight athletes (48 pitchers, 50 position players) were followed for a single select fast-pitch softball season. Study participants completed web-based surveys every 3 weeks reporting injuries related to participation in fast-pitch softball. Injury was defined as pain causing cessation of participation in the current game or practice that prevents the player’s return to that session or any pain that causes cessation of a player’s customary participation on the day after the day of onset. Results: The median age of the study participants was 14 years (range, 9-18 years). There were 49 reported injuries in 98 athletes. The average age was 13 years for those not injured and 14 years for those who were injured (P softball players. Better off-season and preseason conditioning may be a key factor for reducing pitching injuries. Clinical Relevance: Recognition of injury patterns in fast-pitch softball players is critical to developing strategies to keep these athletes competing safely. PMID:26502442

High School Football and Late-Life Risk of Neurodegenerative Syndromes, 1956-1970.

Science.gov (United States)

Janssen, Pieter H H; Mandrekar, Jay; Mielke, Michelle M; Ahlskog, J Eric; Boeve, Bradley F; Josephs, Keith; Savica, Rodolfo

2017-01-01

To assess whether athletes who played American varsity high school football between 1956 and 1970 have an increased risk of neurodegenerative diseases later in life. We identified all male varsity football players between 1956 and 1970 in the public high schools of Rochester, Minnesota, and non-football-playing male varsity swimmers, wrestlers, and basketball players. Using the medical records linkage system of the Rochester Epidemiology Project, we ascertained the incidence of late-life neurodegenerative diseases: dementia, parkinsonism, and amyotrophic lateral sclerosis. We also recorded medical record-documented head trauma during high school years. We identified 296 varsity football players and 190 athletes engaging in other sports. Football players had an increased risk of medically documented head trauma, especially if they played football for more than 1 year. Compared with nonfootball athletes, football players did not have an increased risk of neurodegenerative disease overall or of the individual conditions of dementia, parkinsonism, and amyotrophic lateral sclerosis. In this community-based study, varsity high school football players from 1956 to 1970 did not have an increased risk of neurodegenerative diseases compared with athletes engaged in other varsity sports. This was from an era when there was a generally nihilistic view of concussion dangers, less protective equipment, and no prohibition of spearing (head-first tackling). However, the size and strength of players from previous eras may not be comparable with that of current high school athletes. Copyright © 2016 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.

A COMPARISON OF THE ANTHROPOMETRIC PARAMETERS BETWEEN BASKETBALL PLAYERS, HANDBALL PLAYERS AND VOLLEYBALL PLAYERS

OpenAIRE

Florian Miftari; Juel Jarani; Dhimitraq Stratoberdha; Hazir Salihu

2017-01-01

The purpose of this study was to compare the anthropometric measurement to the professional players of the three different disciplines of basketball, handball and volleyball. . For each player anthropometric measurements such as weight, body height, waist circumference, BMI and skinfold calculation on different sports are performed. Differences in terms of anthropometric measurements were assessed by independent static tests and the differences for each variable for each sport were evaluated ...

Epidemiology of injuries in Australian school level rugby union.

Science.gov (United States)

Leung, Felix T; Franettovich Smith, Melinda M; Brown, Mark; Rahmann, Ann; Mendis, M Dilani; Hides, Julie A

2017-08-01

There is a high incidence of injuries in rugby union due to the physical nature of the game. There is a lack of large-scale injury surveillance data reported for school level rugby players of different ages. Our study aimed to investigate the frequency and nature of injuries being sustained during an Australian school level rugby union season. Prospective observational study. Injury surveillance was conducted on 3585 rugby players from all 8 schools participating in an interschool rugby competition in Queensland, Australia. Match injury data were collected using paper-based injury recording forms during the season using a 'medical-attention' injury definition for each age group from opens (17 and 18year olds) through to year 5 teams (9-10year olds). There were 332 injuries recorded over 14,029 player hours during the season. The overall rate of injury was 23.7/1000 player hours (95% CI, 21.2-26.3). The incidence of upper and lower limb injuries were 6.3 and 5.6 injuries/1000 player hours respectively (95% CI, 5.1-7.8 and 4.5-7.0). The incidence of suspected concussion injuries was 4.3/1000 player hours (95% CI, 3.6-5.5). Injuries differed across age groups and tackling was the most common mechanism of injury. The injury patterns observed in this large sample of players could be used to guide injury prevention programs in school level rugby union. Injury prevention programs should include age appropriate interventions and focus on improving the techniques used during the contact phase of rugby. Copyright © 2017 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Suicide Mortality Among Retired National Football League Players Who Played 5 or More Seasons.

Science.gov (United States)

Lehman, Everett J; Hein, Misty J; Gersic, Christine M

2016-10-01

There is current disagreement in the scientific literature about the relationship between playing football and suicide risk, particularly among professional players in the National Football League (NFL). While some research indicates players are at high risk of football-related concussions, which may lead to chronic traumatic encephalopathy and suicide, other research finds such a connection to be speculative and unsupported by methodologically sound research. To compare the suicide mortality of a cohort of NFL players to what would be expected in the general population of the United States. Cohort study; Level of evidence, 3. A cohort of 3439 NFL players with at least 5 credited playing seasons between 1959 and 1988 was assembled for statistical analysis. The vital status for this cohort was updated through 2013. Standardized mortality ratios (SMRs), the ratio of observed deaths to expected deaths, and 95% CIs were computed for the cohort; 95% CIs that excluded unity were considered statistically significant. For internal comparison purposes, standardized rate ratios were calculated to compare mortality results between players stratified into speed and nonspeed position types. Suicide among this cohort of professional football players was significantly less than would be expected in comparison with the United States population (SMR = 0.47; 95% CI, 0.24-0.82). There were no significant differences in suicide mortality between speed and nonspeed position players. There is no indication of elevated suicide risk in this cohort of professional football players with 5 or more credited seasons of play. Because of the unique nature of this cohort, these study results may not be applicable to professional football players who played fewer than 5 years or to college or high school players. © 2016 The Author(s).

29 CFR 570.35 - Hours of work and conditions of employment permitted for minors 14 and 15 years of age.

Science.gov (United States)

2010-07-01

..., football, soccer, tennis, etc., the requirements of paragraphs (a)(2) through (a)(6) of this section shall..., drinks, towels, etc., to players during play; running errands for trainers, managers, coaches, and...-attending services at professional sporting events, i.e., baseball, basketball, football, soccer, tennis...

The association of foot arch posture and prior history of shoulder or elbow surgery in elite-level baseball pitchers.

Science.gov (United States)

Feigenbaum, Luis A; Roach, Kathryn E; Kaplan, Lee D; Lesniak, Bryson; Cunningham, Sean

2013-11-01

Case-control. The specific aim of this study was to examine the association between abnormal foot arch postures and a history of shoulder or elbow surgery in baseball pitchers. Pitching a baseball generates forces throughout the musculoskeletal structures of the upper and lower limbs. Structures such as the longitudinal arch of the foot are adaptable to stresses over time. Repeated pitching-related stresses may contribute to acquiring abnormal foot arch postures. Inversely, congenitally abnormal foot arch posture may lead to altered stresses of the upper limb during pitching. A convenience sample of 77 pitchers was recruited from a Division I university team and a professional baseball franchise. Subjects who had a history of shoulder or elbow surgery to the pitching arm were classified as cases. Subjects who met the criteria for classification of pes planus or pes cavus based on longitudinal arch angle were classified as having abnormal foot arch posture. Odds ratios were calculated to examine the association between abnormal foot arch posture and pitching-arm injury requiring surgery. Twenty-three subjects were classified as cases. The odds of being a case were 3.4 (95% confidence interval: 1.2, 9.6; P = .02) times greater for subjects with abnormal foot arch posture and 2.9 (95% confidence interval: 1.0, 8.1; P = .04) times greater for subjects with abnormal foot posture on the lunge leg. Abnormal foot arch posture and a surgical history in the pitching shoulder or elbow may be associated. Because the foot and its arches are adaptable and change over time, the pathomechanics of this association should be further explored.

Training strategy of explosive strength in young female volleyball players.

Science.gov (United States)

Pereira, Ana; Costa, Aldo M; Santos, Patricia; Figueiredo, Teresa; João, Paulo Vicente

2015-01-01

The aim of this study was to examine the effect of an 8-week combined jump and ball throwing training program in the performance of upper and lower extremities among young female volleyball players of the high school. A total of 20 young female volleyball players playing at Scholar Sport in High School at the district level were divided in two groups: the experimental group (n=10; 14.0±0.0 years; 1.6±0.1 m; 52.0±7.0 kg and 20.7±2.4% body mass) and the control group (n=10; 13.8±0.4 years, 1.6±0.1 m; 53.5±4.7 kg and 20.3±1.7% body mass). The experimental group received additional plyometric and ball throwing exercises besides their normal volleyball practice. The control group underwent only their regular session of training. Strength performance in the experimental group significantly improved (medicine ball and volleyball ball throwing: P=0.00; and counter movement jump: P=0.05), with the improvement ranging from 5.3% to 20.1%. No significant changes in strength performance were observed in the control group (P>0.05). The 8-week combined jump and ball throwing training can significantly improve muscular performance in young female volleyball players. These findings may be useful for all physical education teachers and volleyball coaches. Copyright © 2015 Lithuanian University of Health Sciences. Production and hosting by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

Out-of-Hospital Cardiac Arrests During the Japanese Professional Baseball Championship Series.

Science.gov (United States)

Onozuka, Daisuke; Hagihara, Akihito

2018-03-14

Because the Japan Professional Baseball Championship Series (Japan Series) is a stressful sports event, it is possible that watching Japan Series matches may increase the risk of cardiovascular events. Therefore, we investigated the potential association between the Japan Series and the incidence of out-of-hospital cardiac arrest (OHCA) events. National registry data for all cases of OHCA between 2005 and 2014 from 47 prefectures of Japan were obtained. We used a time-stratified case-crossover design with a conditional Poisson regression model to compare OHCA events during the Japan Series with those events that occurred during the periods except for dates of the Japan Series. The estimated associations for each prefecture were pooled at the nationwide level using a random-effects meta-analysis. In total, 666,020 OHCAs of presumed cardiac origin were reported during the study period. On days of Japan Series matches, the pooled relative risk of OHCA was 1.033 (95% confidence interval 1.012 to 1.055; p = 0.002; I 2  = 3.5%, P for heterogeneity = 0.405). Stratified analyses by gender revealed that the substantial increase in OHCA during the events was observed for men, whereas we found no significant increase for women. We also found a considerable rise in OHCA among patients aged ≥65 years; however, there was no significant evidence of increased risk in those aged 18 to 64 years. In conclusion, stressful baseball match is associated with an increased risk of OHCA. Prevention measures for severe emotional stress-related OHCA should be implemented, particularly for elderly men. Copyright © 2018 Elsevier Inc. All rights reserved.

The 1985 ARI Survey of Army Recruits: User’s Manual

Science.gov (United States)

1986-05-01

league baseball regular season games 2 3 99. Major leagus baseball playoffs 1 2 3 4 100. World Series 1 2 3 4 101. NBA basketball 1 2 3 4 102...did you participate in while you were in high school? (CIRCLE ALL THAT APPLY) Football ....................... 1 Basketball ..................... 2...I Basketball ...................... 2 Swimming....................... 3 4P Baseball ....................... Track

Player and Game Characteristics and Head Impacts in Female Youth Ice Hockey Players.

Science.gov (United States)

Reed, Nick; Taha, Tim; Greenwald, Richard; Keightley, Michelle

2017-08-01

  Despite the growing popularity of ice hockey among female youth and interest in the biomechanics of head impacts in sport, the head impacts sustained by this population have yet to be characterized.   To describe the number of, biomechanical characteristics of, and exposure to head impacts of female youth ice hockey players during competition and to investigate the influences of player and game characteristics on head impacts.   Cohort study.   Twenty-seven female youth ice hockey players (mean age = 12.5 ± 0.52 years) wore instrumented ice hockey helmets during 66 ice hockey games over a 3-year period. Data specific to player, game, and biomechanical head impact characteristics were recorded. A multiple regression analysis identified factors most associated with head impacts of greater frequency and severity.   A total of 436 total head impacts were sustained during 6924 minutes of active ice hockey participation (0.9 ± 0.6 impacts per player per game; range, 0-2.1). A higher body mass index (BMI) significantly predicted a higher number of head impacts sustained per game (P = .008). Linear acceleration of head impacts was greater in older players and those who played the forward position, had a greater BMI, and spent more time on the ice (P = .008), whereas greater rotational acceleration was present in older players who had a greater BMI and played the forward position (P = .008). During tournament games, increased ice time predicted increased severity of head impacts (P = .03).   This study reveals for the first time that head impacts are occurring in female youth ice hockey players, albeit at a lower rate and severity than in male youth ice hockey players, despite the lack of intentional body checking.

STS-95 Payload Specialist Glenn greets baseball legend Williams following a parade in Cocoa Beach

Science.gov (United States)

1998-01-01

STS-95 Payload Specialist John H. Glenn Jr. (left) greets baseball legend Ted Williams at a reception at the Double Tree Oceanfront Hotel following a parade down State Road A1A in nearby Cocoa Beach. Organizers of the parade included the Cocoa Beach Area Chamber of Commerce, the Brevard County Tourist Development Council, and the cities of Cape Canaveral and Cocoa Beach. The parade is reminiscent of those held after missions during the Mercury Program.

The Effects of Playing Multiple High School Sports on National Basketball Association Players' Propensity for Injury and Athletic Performance.

Science.gov (United States)

Rugg, Caitlin; Kadoor, Adarsh; Feeley, Brian T; Pandya, Nirav K

2018-02-01

Athletes who specialize in their sport at an early age may be at risk for burnout, overuse injury, and reduced attainment of elite status. Timing of sport specialization has not been studied in elite basketball athletes. National Basketball Association (NBA) players who played multiple sports during adolescence would be less likely to experience injury and would have higher participation rates in terms of games played and career length compared with single-sport athletes. Descriptive epidemiology study. First-round draft picks from 2008 to 2015 in the NBA were included in the study. From publically available records from the internet, the following data were collected for each athlete: participation in high school sports, major injuries sustained in the NBA, percentage of games played in the NBA, and whether the athlete was still active in the NBA. Athletes who participated in sports in addition to basketball during high school were defined as multisport athletes and were compared with athletes who participated only in basketball in high school. Two hundred thirty-seven athletes were included in the study, of which 36 (15%) were multisport athletes and 201 (85%) were single-sport athletes in high school. The multisport cohort played in a statistically significantly greater percentage of total games (78.4% vs 72.8%; P NBA (94% vs 81.1%; P = .03). While a minority of professional basketball athletes participated in multiple sports in high school, those who were multisport athletes participated in more games, experienced fewer major injuries, and had longer careers than those who participated in a single sport. Further research is needed to determine the reasons behind these differences.

The effect of winter sports participation on high school football players: strength, power, agility, and body composition.

Science.gov (United States)

Wroble, R R; Moxley, D R

2001-02-01

In this study, football players (N = 57) in grades 9-11 from 3 high schools chose to participate in 1 of 2 groups. Group WC (N = 39) participated in off-season strength training only. Group SP (N = 18) participated in both a winter sport (either wrestling or basketball) and an identical strength training program. All participants were tested at the close of football season (Pre) and at the end of the winter sports season (Post), a period of 4 months. Body composition (weight [W] and body fat percentage [BF]), strength (calculated 1RM [1 repetition maximum] max for barbell bench press [BP] and squat [SQ]), power (vertical jump [VJ] and seated shot put [UP]), and agility (18.3-m agility run [AG]) were measured. Both groups WC and SP increased significantly in W and BF and improved significantly in BP and VJ (p training.

Lower extremity muscle activation during baseball pitching.

Science.gov (United States)

Campbell, Brian M; Stodden, David F; Nixon, Megan K

2010-04-01

The purpose of this study was to investigate muscle activation levels of select lower extremity muscles during the pitching motion. Bilateral surface electromyography data on 5 lower extremity muscles (biceps femoris, rectus femoris, gluteus maximus, vastus medialis, and gastrocnemius) were collected on 11 highly skilled baseball pitchers and compared with individual maximal voluntary isometric contraction (MVIC) data. The pitching motion was divided into 4 distinct phases: phase 1, initiation of pitching motion to maximum stride leg knee height; phase 2, maximum stride leg knee height to stride foot contact (SFC); phase 3, SFC to ball release; and phase 4, ball release to 0.5 seconds after ball release (follow-through). Results indicated that trail leg musculature elicited moderate to high activity levels during phases 2 and 3 (38-172% of MVIC). Muscle activity levels of the stride leg were moderate to high during phases 2-4 (23-170% of MVIC). These data indicate a high demand for lower extremity strength and endurance. Specifically, coaches should incorporate unilateral and bilateral lower extremity exercises for strength improvement or maintenance and to facilitate dynamic stabilization of the lower extremities during the pitching motion.

Active Learning for Player Modeling

DEFF Research Database (Denmark)

Shaker, Noor; Abou-Zleikha, Mohamed; Shaker, Mohammad

2015-01-01

Learning models of player behavior has been the focus of several studies. This work is motivated by better understanding of player behavior, a knowledge that can ultimately be employed to provide player-adapted or personalized content. In this paper, we propose the use of active learning for player...... experience modeling. We use a dataset from hundreds of players playing Infinite Mario Bros. as a case study and we employ the random forest method to learn mod- els of player experience through the active learning approach. The results obtained suggest that only part of the dataset (up to half the size...... that the method can be used online during the content generation process where the mod- els can improve and better content can be presented as the game is being played....

The effects of forearm fatigue on baseball fastball pitching, with implications about elbow injury.

Science.gov (United States)

Wang, Lin-Hwa; Lo, Kuo-Cheng; Jou, I-Ming; Kuo, Li-Chieh; Tai, Ta-Wei; Su, Fong-Chin

2016-01-01

This study investigated the contribution of flexor muscles to the forearm through fatigue; therefore, the differences in forearm mechanisms on the pitching motion in fastball were analysed. Fifteen baseball pitchers were included in this study. Ultrasonographical examination of participants' ulnar nerve in the cubital tunnel with the elbow extended and at 45°, 90° and 120° of flexion was carried. A three-dimensional motion analysis system with 14 reflective markers attached on participants was used for motion data collection. The electromyography system was applied over the flexor carpi ulnaris, flexor carpi radialis and extensor carpi radialis muscles of the dominant arm. Flexor carpi ulnaris muscle activity showed a significant difference during the acceleration phase, with a peak value during fastball post-fatigue (P = 0.02). Significant differences in the distance between ulnar nerve and medial condyle on throwing arm and non-throwing arm were observed as the distance increased with the elbow movement from 0° to 120° of flexion (P = 0.01). The significant increase of the flexor carpi ulnaris muscle activity might be responsible for maintaining the stability of the wrist joint. The increased diameter might compress the ulnar nerve and cause several pathological changes. Therefore, fatigue in baseball pitchers still poses a threat to the ulnar nerve because the flexor carpi ulnaris and flexor carpi radialis all originate from the medial side of the elbow, and the swelling tendons after fatigue might be a key point.

Participation in Pre-High School Football and Neurological, Neuroradiological, and Neuropsychological Findings in Later Life: A Study of 45 Retired National Football League Players.

Science.gov (United States)

Solomon, Gary S; Kuhn, Andrew W; Zuckerman, Scott L; Casson, Ira R; Viano, David C; Lovell, Mark R; Sills, Allen K

2016-05-01

A recent study found that an earlier age of first exposure (AFE) to tackle football was associated with long-term neurocognitive impairment in retired National Football League (NFL) players. To assess the association between years of exposure to pre-high school football (PreYOE) and neuroradiological, neurological, and neuropsychological outcome measures in a different sample of retired NFL players. Cross-sectional study; Level of evidence, 3. Forty-five former NFL players were included in this study. All participants prospectively completed extensive history taking, a neurological examination, brain magnetic resonance imaging, and a comprehensive battery of neuropsychological tests. To measure the associations between PreYOE and these outcome measures, multiple regression models were utilized while controlling for several covariates. After applying a Bonferroni correction for multiple comparisons, none of the neurological, neuroradiological, or neuropsychological outcome measures yielded a significant relationship with PreYOE. A second Bonferroni-corrected analysis of a subset of these athletes with self-reported learning disability yielded no significant relationships on paper-and-pencil neurocognitive tests but did result in a significant association between learning disability and computerized indices of visual motor speed and reaction time. The current study failed to replicate the results of a prior study, which concluded that an earlier AFE to tackle football might result in long-term neurocognitive deficits. In 45 retired NFL athletes, there were no associations between PreYOE and neuroradiological, neurological, and neuropsychological outcome measures. © 2016 The Author(s).

Music-listening habits with MP3 player in a group of adolescents: a descriptive survey.

Science.gov (United States)

Pellegrino, E; Lorini, C; Allodi, G; Buonamici, C; Garofalo, G; Bonaccorsi, G

2013-01-01

Listening to music through portable MP3 players has become a very popular mode among young people and adolescents. The aim of this study is to investigate the behaviors of adolescents engaged in listening to music with MP3 player and the attendance at clubs (pubs, discotheques) where music is played at high volume. Among the 1470 students attending a secondary school in Scandicci (FI) during the school year 2009/2010, 1278 (86.9%) were at school the day of the examination and 1276 completely filled in the questionnaire. Descriptive analysis and univariate and multivariate logistic regression were performed to calculate the degree of association (OR) among the sociodemographic characteristics, listening habits and some factors identified as risky or protective as regards the possibility of developing health disorders. MP3 player users are 88.2% of the sample. Among these, a high proportion engaged behaviours that increase the risk of presenting disorders, including the exposure to high-volume (27.4%). Furthermore, 44.6% use the MP3 while driving. From the regression analysis it emerges that MP3 users showed a sort of addiction: by increasing the time and the occasions of exposure to music, they increased the volume, used maximum or medium-high volume, did not take breaks and did not decrease the volume. The study points out the spread of risky behavior in music listening, so it is necessary to better inform especially the youngsters and achieve specific preventive interventions.

Physical fitness of elite Belgian soccer players by player position.

Science.gov (United States)

Boone, Jan; Vaeyens, Roel; Steyaert, Adelheid; Vanden Bossche, Luc; Bourgois, Jan

2012-08-01

The purpose of this study was to gain an insight into the physical and physiological profile of elite Belgian soccer players with specific regard to the player's position on the field. The sample consisted of 289 adult players from 6 different first division teams. The players were divided into 5 subgroups (goalkeepers, center backs, full backs, midfielders, and strikers) according to their self-reported best position on the field. The subjects performed anaerobic (10-m sprint, 5 × 10-m shuttle run [SR], squat jump [SJ], and countermovement jump [CMJ]) and aerobic (incremental running protocol) laboratory tests. The strikers had significantly shorter sprinting times (5-, 5- to 10-m time, and SR) compared with the midfielders, center backs, and goalkeepers, whereas the full backs were also significantly faster compared with the goalkeepers and the center backs. The goalkeepers and the center backs displayed higher jumping heights (total mean SJ = 40.7 ± 4.6 cm and CMJ = 43.1 ± 4.9 cm) compared with the other 3 positions, whereas the strikers also jumped higher than the full backs and the midfielders did. Regarding the aerobic performance, both full backs and the midfielders (61.2 ± 2.7 and 60.4 ± 2.8 ml · min(-1) · kg(-1), respectively) had a higher VO2max compared with the strikers, center backs, and goalkeepers (56.8 ± 3.1, 55.6 ± 3.5, and 52.1 ± 5.0 ml · min(-1) · kg(-1), respectively). From this study, it could be concluded that players in different positions have different physiological characteristics. The results of this study might provide useful insights for individualized conditional training programs for soccer players. Aside from the predominant technical and tactical skills, a physical profile that is well adjusted to the position on the field might enhance game performance.

Brand Equity, Efficiency and Valuation of Professional Sports Franchises: The Case of Major League Baseball

OpenAIRE

Srinivas K Reddy; Antonie Stam; Per J Agrell

2015-01-01

Values of professional sports franchises have outpaced even investment returns in recent bull markets. Financial World found the value of professional teams like the Dallas Cowboys, Miami Dolphins and the NY Yankees to exceed $200 million each. In 1996, the average estimated value of Major League Baseball (MLB) teams was $134 million, and most showed double-digit growth in value, although 13 of the 26 teams were in the red. Our research proposes a model to determine the value of a professiona...

A test battery for the determination of positional requirements in adolescent rugby players / Maria Magdalena van Gent

OpenAIRE

Van Gent, Maria Magdalena

2003-01-01

Motivation Rugby is a very popular sport and is played from primary school to senior level in more than a hundred countries world-wide (Pretorius, 1997:2). South Africa is no exception; it has been known to be the breeding ground/or some of the world's greatest players (Granger, 2002:56). According to Pienaar and Spamer (1998:14) certain anthropometric, physical, motor abilities and game-specific variables can distinguish between talented and less talented rugby players. How...

Sport or School? Dreams and Dilemmas for Talented Young Danish Football Players

Science.gov (United States)

Christensen, Mette Krogh; Sorensen, Jan Kahr

2009-01-01

Today's young semi-professional football players are expected to continue their education while honing their talents as footballers. This means they must balance the contradictory demands that come from their education establishments and their football clubs. The present study explores how young Danish male football talents experience and describe…

High-school football and late-life risk of neurodegenerative syndromes, 1956–1970

Science.gov (United States)

Janssen, Pieter HH; Mandrekar, Jay; Mielke, Michelle M; Ahlskog, J. Eric; Boeve, Bradley F; Josephs, Keith; Savica, Rodolfo

2017-01-01

BACKGROUND Repeated head trauma has been associated with risk of neurodegenerative diseases. Few studies have evaluated the long-term risk of neurodegenerative diseases in collision sports like football. OBJECTIVE To assess whether athletes who played American varsity high-school football between 1956 and 1970 have an increased risk of neurodegenerative diseases later in life. PATIENTS AND METHODS We identified all male varsity football players between 1956 and 1970 in the public high schools of Rochester, Minnesota, compared to non-football-playing male varsity swimmers, wrestlers or basketball players. Using the records-linkage system of the Rochester Epidemiology Project, we ascertained the incidence of late-life neurodegenerative diseases: dementia, parkinsonism, or amyotrophic lateral sclerosis. We also recorded medical record-documented head trauma during high school years. RESULTS We identified 296 varsity football players and 190 athletes engaging in other sports. Football players had an increased risk of medically documented head trauma, especially if they played football for more than one year. Compared to non-football athletes, football players did not have an increased risk of neurodegenerative disease overall, nor the individual conditions of dementia, parkinsonism, or amyotrophic lateral sclerosis. CONCLUSION In this community based study, varsity high school football players from 1956 to 1970 did not have an increased risk of developing neurodegenerative diseases compared with athletes engaged in other varsity sports. This was from an era where there was a generally nihilistic view of concussion dangers, less protective equipment and without prohibition of spearing (head-first tackling). However, size and strength of players from prior eras may not be comparable to current high-school athletes. PMID:27979411

The body composition, nutritional knowledge, attitudes, behaviors, and future education needs of senior schoolboy rugby players in Ireland.

Science.gov (United States)

Walsh, Michelle; Cartwright, Laura; Corish, Clare; Sugrue, Sheila; Wood-Martin, Ruth

2011-10-01

This study examined the body composition, nutritional knowledge, behaviors, attitudes, and educational needs of senior schoolboy rugby players in Ireland. Participants included 203 male rugby players age 15-18 yr competing at Senior School's Cup level in Leinster, Ireland. Estimation of body composition included measurement of height, weight, and percentage body fat (PBF; using bioelectrical impedance analysis, Tanita BC-418). Nutritional knowledge, behaviors, attitudes, and education needs were assessed by questionnaire. The range of PBF was 5.1-25.3%. Sixty-eight percent of the players in this study had a healthy PBF (10-20%), 32 (22%) were classified as underweight (benefit from appropriate nutritional education.

Participants in school-sponsored and independent sports: perceptions of self and family.

Science.gov (United States)

Browne, B A; Francis, S K

1993-01-01

Sports are believed to contribute to physical well-being, social adjustment, and self-esteem. In this study, perceptions of social competence and family dynamics were examined among adolescent participants in school-sponsored and independent sports (baseball and skateboarding). Subjects, aged 12 to 19 years, completed a questionnaire consisting of FACES III, a social competence scale, and miscellaneous items concerning school performance, sports commitment, and perceptions of adult attitudes. Perceptions of social competence were differentially related to degree of sports involvement and perceived skill but were not related to the social acceptability of the sport. Adolescents in both groups depicted their families as demonstrating low levels of cohesion but high adaptability.

An Analysis of Creative Process Learning in Computer Game Activities Through Player Experiences

Directory of Open Access Journals (Sweden)

Wilawan Inchamnan

2016-09-01

Full Text Available This research investigates the extent to which creative processes can be fostered through computer gaming. It focuses on creative components in games that have been specifically designed for educational purposes: Digital Game Based Learning (DGBL. A behavior analysis for measuring the creative potential of computer game activities and learning outcomes is described. Creative components were measured by examining task motivation and domain-relevant and creativity-relevant skill factors. The research approach applied heuristic checklists in the field of gameplay to analyze the stage of player activities involved in the performance of the task and to examine player experiences with the Player Experience of Need Satisfaction (PENS survey. Player experiences were influenced by competency, autonomy, intuitive controls, relatedness and presence. This study examines the impact of these activities on the player experience for evaluating learning outcomes through school records. The study is designed to better understand the creative potential of people who are engaged in learning knowledge and skills during the course while playing video games. The findings show the creative potential that occurred to yield levels of creative performance within game play activities to support learning. The anticipated outcome is knowledge on how video games foster creative thinking as an overview of the Creative Potential of Learning Model (CPLN. CPLN clearly describes the interrelationships between principles of learning and creative potential, the interpretation of the results is indispensable.

Technical player profiles related to the physical fitness of young female volleyball players predict team performance.

Science.gov (United States)

Dávila-Romero, C; Hernández-Mocholí, M A; García-Hermoso, A

2015-03-01

This study is divided into three sequential stages: identification of fitness and game performance profiles (individual player performance), an assessment of the relationship between these profiles, and an assessment of the relationship between individual player profiles and team performance during play (in championship performance). The overall study sample comprised 525 (19 teams) female volleyball players aged 12-16 years and a subsample (N.=43) used to examine study aims one and two was selected from overall sample. Anthropometric, fitness and individual player performance (actual game) data were collected in the subsample. These data were analyzed through clustering methods, ANOVA and independence chi-square test. Then, we investigated whether the proportion of players with the highest individual player performance profile might predict a team's results in the championship. Cluster analysis identified three volleyball fitness profiles (high, medium, and low) and two individual player performance profiles (high and low). The results showed a relationship between both types of profile (fitness and individual player performance). Then, linear regression revealed a moderate relationship between the number of players with a high volleyball fitness profile and a team's results in the championship (R2=0.23). The current study findings may enable coaches and trainers to manage training programs more efficiently in order to obtain tailor-made training, identify volleyball-specific physical fitness training requirements and reach better results during competitions.

Prevalence of and Attitudes about Concussion in Irish Schools' Rugby Union Players

Science.gov (United States)

Delahunty, Sinéad E.; Delahunt, Eamonn; Condon, Brian; Toomey, David; Blake, Catherine

2015-01-01

Background: Youth rugby players represent 45.2% (N?=?69,472) of the Irish rugby union playing population. The risk and consequences of concussion injury are of particular concern in these young athletes, but limited epidemiological data exists. This study investigated annual and lifetime prevalence of concussion in an Irish schoolboy rugby union…

Acute effects of various weighted bat warm-up protocols on bat velocity.

Science.gov (United States)

Reyes, G Francis; Dolny, Dennis

2009-10-01

Although research has provided evidence of increased muscular performance following a facilitation set of resistance exercise, this has not been established for use prior to measuring baseball bat velocity. The purpose of this study was to determine the effectiveness of selected weighted bat warm-up protocols to enhance bat velocity in collegiate baseball players. Nineteen collegiate baseball players (age = 20.15 +/- 1.46 years) were tested for upper-body strength by a 3-repetition maximum (RM) bench press (mean = 97.98 +/- 14.54 kg) and mean bat velocity. Nine weighted bat warm-up protocols, utilizing 3 weighted bats (light = 794 g; standard = 850 g; heavy = 1,531 g) were swung in 3 sets of 6 repetitions in different orders. A control trial involved the warm-up protocol utilizing only the standard bat. Pearson product correlation revealed a significant relationship between 3RM strength and pretest bat velocity (r = 0.51, p = 0.01). Repeated measures analysis of variance (ANOVA) revealed no significant treatment effects of warm-up protocol on bat velocity. However, the order of standard, light, heavy bat sequence resulted in the greatest increase in bat velocity (+6.03%). These results suggest that upper-body muscle strength influences bat velocity. It appears that the standard, light, heavy warm-up order may provide the greatest benefit to increase subsequent bat velocity and may warrant use in game situations.

MythBusters, Musicians, and MP3 Players: A Middle School Sound Study

Science.gov (United States)

Putney, Ann

2011-01-01

Create your own speakers for an MP3 player while exploring the science of sound. Review of science notebooks, students' intriguing cabinet designs, and listening to students talk with a musician about the physics of an instrument show that complex concepts are being absorbed and extended with each new iteration. Science that matters to students…

Excel, Earthquakes, and Moneyball: exploring Cascadia earthquake probabilities using spreadsheets and baseball analogies

Science.gov (United States)

Campbell, M. R.; Salditch, L.; Brooks, E. M.; Stein, S.; Spencer, B. D.

2017-12-01

Much recent media attention focuses on Cascadia's earthquake hazard. A widely cited magazine article starts "An earthquake will destroy a sizable portion of the coastal Northwest. The question is when." Stories include statements like "a massive earthquake is overdue", "in the next 50 years, there is a 1-in-10 chance a "really big one" will erupt," or "the odds of the big Cascadia earthquake happening in the next fifty years are roughly one in three." These lead students to ask where the quoted probabilities come from and what they mean. These probability estimates involve two primary choices: what data are used to describe when past earthquakes happened and what models are used to forecast when future earthquakes will happen. The data come from a 10,000-year record of large paleoearthquakes compiled from subsidence data on land and turbidites, offshore deposits recording submarine slope failure. Earthquakes seem to have happened in clusters of four or five events, separated by gaps. Earthquakes within a cluster occur more frequently and regularly than in the full record. Hence the next earthquake is more likely if we assume that we are in the recent cluster that started about 1700 years ago, than if we assume the cluster is over. Students can explore how changing assumptions drastically changes probability estimates using easy-to-write and display spreadsheets, like those shown below. Insight can also come from baseball analogies. The cluster issue is like deciding whether to assume that a hitter's performance in the next game is better described by his lifetime record, or by the past few games, since he may be hitting unusually well or in a slump. The other big choice is whether to assume that the probability of an earthquake is constant with time, or is small immediately after one occurs and then grows with time. This is like whether to assume that a player's performance is the same from year to year, or changes over their career. Thus saying "the chance of

What is Skilled Coping?

DEFF Research Database (Denmark)

Høffding, Simon

2014-01-01

or reflecting. He uses examples from various experts, such a chess-, baseball-, and soccer players, to illustrate this. I argue that his account suffers from a reductive dualism between coping and reflection and further from a lack of clarity. I use my work with the string quartet to illustrate that so...

Academic Moneyball

Science.gov (United States)

Dustin, Dan; Murphy, James; McDonald, Cary; Wright, Brett; Harper, Jack; Lamke, Gene

2014-01-01

We apply lessons from "Moneyball," Michael Lewis's (2003) best-selling account of the Oakland Athletics's use of "sabermetrics" to find undervalued baseball players to help build a cost-effective team to the context of recreation, park, and leisure studies. Specifically, we coin and apply the term…

MP3 Players and Hearing Loss: Adolescents' Perceptions of Loud Music and Hearing Conservation

NARCIS (Netherlands)

Vogel, I.; Brug, J.; Hosli, E.J.; Ploeg, C.P.B. van der; Raat, H.

2008-01-01

Objective: To explore adolescents' behaviors and opinions about exposure to loud music from MP3 players. Study design: We conducted a qualitative analysis of focus-group discussions with adolescents aged 12 to 18 years from 2 large secondary schools (1 urban and 1 rural) for pre-vocational and

A Method for Using Player Tracking Data in Basketball to Learn Player Skills and Predict Team Performance.

Science.gov (United States)

Skinner, Brian; Guy, Stephen J

2015-01-01

Player tracking data represents a revolutionary new data source for basketball analysis, in which essentially every aspect of a player's performance is tracked and can be analyzed numerically. We suggest a way by which this data set, when coupled with a network-style model of the offense that relates players' skills to the team's success at running different plays, can be used to automatically learn players' skills and predict the performance of untested 5-man lineups in a way that accounts for the interaction between players' respective skill sets. After developing a general analysis procedure, we present as an example a specific implementation of our method using a simplified network model. While player tracking data is not yet available in the public domain, we evaluate our model using simulated data and show that player skills can be accurately inferred by a simple statistical inference scheme. Finally, we use the model to analyze games from the 2011 playoff series between the Memphis Grizzlies and the Oklahoma City Thunder and we show that, even with a very limited data set, the model can consistently describe a player's interactions with a given lineup based only on his performance with a different lineup.

Adaptability of expert visual anticipation in baseball batting.

Science.gov (United States)

Müller, Sean; Fadde, Peter J; Harbaugh, Allen G

2017-09-01

By manipulating stimulus variation in terms of opponent pitcher actions, this study investigated the capability of expert (n = 30) and near-expert (n = 95) professional baseball batters to adapt anticipation skill when using the video simulation temporal occlusion paradigm. Participants watched in-game footage of two pitchers, one after the other, that was temporally occluded at ball release and various points during ball flight. They were required to make a written prediction of pitch types and locations. Per cent accuracy was calculated for pitch type, for pitch location, and for type and location combined. Results indicated that experts and near-experts could adapt their anticipation to predict above guessing level across both pitchers, but adaptation to the left-handed pitcher was poorer than the right-handed pitcher. Small-to-moderate effect sizes were found in terms of superior adaptation by experts over near-experts at the ball release and early ball flight occlusion conditions. The findings of this study extend theoretical and applied knowledge of expertise in striking sports. Practical application of the instruments and findings are discussed in terms of applied researchers, practitioners and high-performance staff in professional sporting organisations.

Sleep-apnea risk and subclinical atherosclerosis in early-middle-aged retired National Football League players

Directory of Open Access Journals (Sweden)

Luyster FS

2017-02-01

Full Text Available Faith S Luyster,1 Reginald E Dunn,2 Diane S Lauderdale,3 Mercedes R Carnethon,4 Andrew M Tucker,5 Robert A Vogel,6 Andrew E Lincoln,2 Kristen L Knutson,7 Elliot J Pellman,8–10 Patrick J Strollo Jr11 1School of Nursing, University of Pittsburgh, Pittsburgh, PA, 2Sports Medicine Research Center, MedStar Health Research Institute, Baltimore, MD, 3Department of Public Health Sciences, University of Chicago, 4Department of Preventive Medicine, Northwestern University, Chicago, IL, 5MedStar Sports Medicine, MedStar Union Memorial Hospital, Baltimore, MD, 6Cardiology Section, Department of Veterans Affairs Medical Center, Denver, CO, 7Department of Medicine, University of Chicago, Chicago, IL, 8ProHealth Care Associates, Lake Success, 9Department of Medicine, 10Department of Orthopedics, Mount Sinai School of Medicine, New York, NY, 11Department of Pulmonary, Allergy, and Critical Care Medicine, University of Pittsburgh Medical Center, Pittsburgh, PA, USA Purpose: Limited data from former National Football League (NFL players suggest that obstructive sleep apnea (OSA may be highly prevalent after retirement. It remains unclear whether the high prevalence of OSA in retired players is comparable to nonathletes. This retrospective analysis compared sleep apnea (SA risk in retired NFL players to a community cohort (CARDIA Sleep study, and examined associations between SA risk and cardiovascular risk factors, including subclinical atherosclerosis.Materials and methods: Retired NFL players (n=122 were matched to CARDIA Sleep participants by age ±2 years (range 37–55 years, body mass index ±2 kg/m2, race, and male sex. Participants underwent electron-beam computed tomography to measure coronary artery calcium (CAC and completed the Berlin Questionnaire to determine SA risk. The presence of CAC was defined as an Agatston score >0.Results: Retired NFL players had a greater prevalence of high SA risk than the matched CARDIA Sleep participants (27% vs 11

Musculoskeletal injuries among Malaysian badminton players.

Science.gov (United States)

Shariff, A H; George, J; Ramlan, A A

2009-11-01

The purpose of this study was to investigate the pattern of musculoskeletal injuries sustained by Malaysian badminton players. This is a retrospective case notes review of all badminton players who attended the National Sports Institute (NSI) Clinic, Kuala Lumpur, Malaysia, and were diagnosed with musculoskeletal injuries. In a two and a half year period, from January 2005 to June 2007, 469 musculoskeletal injuries were diagnosed among badminton players at the NSI Clinic. The mean age of the players who attended the clinic was 19.2 (range 13-52) years. Approximately 60 percent of the injuries occurred in players younger than 20 years of age. The majority of injuries (91.5 percent) were categorised as mild overuse injury and mostly involved the knee. The majority of the injuries sustained by badminton players in this study were due to overuse, primarily in the knee. The majority of the injuries were diagnosed in younger players and occurred during training/practice sessions. There was no difference in terms of incidence and types of injuries between the genders.

Vitamin D Deficiency Among Professional Basketball Players.

Science.gov (United States)

Fishman, Matthew P; Lombardo, Stephen J; Kharrazi, F Daniel

2016-07-01

Vitamin D plays an important role in several systems of the human body. Various studies have linked vitamin D deficiency to stress and insufficiency fractures, muscle recovery and function, and athletic performance. The prevalence of vitamin D deficiency in the elite athletic population has not been extensively studied, and very few reports exist among professional athletes. There is a high prevalence of vitamin D deficiency or insufficiency among players attending the National Basketball Association (NBA) Combine. Cross-sectional study; Level of evidence, 3. This is a retrospective review of data previously collected as part of the routine medical evaluation of players in the NBA Combines from 2009 through 2013. Player parameters evaluated were height, weight, body mass index (BMI), and vitamin D level. Statistical analysis using t tests and analysis of variance was used to detect any correlation between the player parameters and vitamin D level. Vitamin D levels were categorized as deficient (32 ng/mL). After institutional review board approval was submitted to the NBA, the NBA released deidentified data on 279 players who participated in the combines from 2009 through 2013. There were 90 players (32.3%) who were deficient, 131 players (47.0%) who were insufficient, and 58 players (20.8%) who were sufficient. A total of 221 players (79.3%) were either vitamin D deficient or insufficient. Among all players included, the average vitamin D level was 25.6 ± 10.2 ng/mL. Among the players who were deficient, insufficient, and sufficient, the average vitamin D levels were 16.1 ± 2.1 ng/mL, 25.0 ± 3.4 ng/mL, and 41.6 ± 8.6 ng/mL, respectively. Player height and weight were significantly increased in vitamin D-sufficient players compared with players who were not sufficient (P = .0008 and .009, respectively). Player age and BMI did not significantly differ depending on vitamin D status (P = .15 and .77, respectively). There is a high prevalence of vitamin D deficiency

Time-motion analysis of goalball players in attacks: differences of the player positions and the throwing techniques.

Science.gov (United States)

Monezi, Lucas Antônio; Magalhães, Thiago Pinguelli; Morato, Márcio Pereira; Mercadante, Luciano Allegretti; Furtado, Otávio Luis Piva da Cunha; Misuta, Milton Shoiti

2018-03-26

In this study, we aimed to analyse goalball players time-motion variables (distance covered, time spent, maximum and average velocities) in official goalball match attacks, taking into account the attack phases (preparation and throwing), player position (centres and wings) and throwing techniques (frontal, spin and between the legs). A total of 365 attacks were assessed using a video based method (2D) through manual tracking using the Dvideo system. Inferential non-parametric statistics were applied for comparison of preparation vs. throwing phase, wings vs. centres and, among the throwing techniques, frontal, spin and between the legs. Significant differences were found between the attack preparation versus the throwing phase for all player time-motion variables: distance covered, time spent, maximum player velocity and average player velocity. Wing players performed most of the throws (85%) and covered longer distances than centres (1.65 vs 0.31 m). The between the legs and the spin throwing techniques presented greater values for most of the time-motion variables (distance covered, time spent and maximum player velocity) than did the frontal technique in both attack phases. These findings provide important information regarding players' movement patterns during goalball matches that can be used to plan more effective training.

A Method for Using Player Tracking Data in Basketball to Learn Player Skills and Predict Team Performance.

Directory of Open Access Journals (Sweden)

Brian Skinner

Full Text Available Player tracking data represents a revolutionary new data source for basketball analysis, in which essentially every aspect of a player's performance is tracked and can be analyzed numerically. We suggest a way by which this data set, when coupled with a network-style model of the offense that relates players' skills to the team's success at running different plays, can be used to automatically learn players' skills and predict the performance of untested 5-man lineups in a way that accounts for the interaction between players' respective skill sets. After developing a general analysis procedure, we present as an example a specific implementation of our method using a simplified network model. While player tracking data is not yet available in the public domain, we evaluate our model using simulated data and show that player skills can be accurately inferred by a simple statistical inference scheme. Finally, we use the model to analyze games from the 2011 playoff series between the Memphis Grizzlies and the Oklahoma City Thunder and we show that, even with a very limited data set, the model can consistently describe a player's interactions with a given lineup based only on his performance with a different lineup.

Finite stage asymmetric repeated games: Both players' viewpoints

KAUST Repository

Li, Lichun

2017-01-05

In asymmetric zero-sum games, one player has superior information about the game over the other. It is known that the informed players (maximizer) face the tradeoff of exploiting its superior information at the cost of revealing its superior information, but the basic point of the uninformed player (minimizer)\\'s decision making remains unknown. This paper studies the finite stage asymmetric repeated games from both players\\' viewpoints, and derives that not only security strategies but also the opponents\\' corresponding best responses depends only on the informed player\\'s history action sequences. Moreover, efficient LP formulations to compute both player\\'s security strategies are provided.

Shoulder instability in professional football players.

Science.gov (United States)

Leclere, Lance E; Asnis, Peter D; Griffith, Matthew H; Granito, David; Berkson, Eric M; Gill, Thomas J

2013-09-01

Shoulder instability is a common problem in American football players entering the National Football League (NFL). Treatment options include nonoperative and surgical stabilization. This study evaluated how the method of treatment of pre-NFL shoulder instability affects the rate of recurrence and the time elapsed until recurrence in players on 1 NFL team. Retrospective cohort. Medical records from 1980 to 2008 for 1 NFL team were reviewed. There were 328 players included in the study who started their career on the team and remained on the team for at least 2 years (mean, 3.9 years; range, 2-14 years). The history of instability prior to entering the NFL and the method of treatment were collected. Data on the occurrence of instability while in the NFL were recorded to determine the rate and timing of recurrence. Thirty-one players (9.5%) had a history of instability prior to entering the NFL. Of the 297 players with no history of instability, 39 (13.1%) had a primary event at a mean of 18.4 ± 22.2 months (range, 0-102 months) after joining the team. In the group of players with prior instability treated with surgical stabilization, there was no statistical difference in the rate of recurrence (10.5%) or the timing to the instability episode (mean, 26 months) compared with players with no history of instability. Twelve players had shoulder instability treated nonoperatively prior to the NFL. Five of these players (41.7%) had recurrent instability at a mean of 4.4 ± 7.0 months (range, 0-16 months). The patients treated nonoperatively had a significantly higher rate of recurrence (P = 0.02) and an earlier time of recurrence (P = 0.04). The rate of contralateral instability was 25.8%, occurring at a mean of 8.6 months. Recurrent shoulder instability is more common in NFL players with a history of nonoperative treatment. Surgical stabilization appears to restore the rate and timing of instability to that of players with no prior history of instability.

Sport or school? Dreams and dilemmas for talented young Danish football players

DEFF Research Database (Denmark)

Christensen, Mette Krogh; Kahr Sørensen, Jan

2009-01-01

  Today's young semi-professional football players are expected to continue their education while honing their talents as footballers. This means they must balance the contradictory demands that come from their education establishments and their football clubs. The present study explores how youn...... of completing a youth education is manifest and associated with significant personal concerns, lower examinations results, stress, drop-out and mental breakdown....

Effects of 6-week sling-based training of the external-rotator muscles on the shoulder profile in elite female high school handball players.

Science.gov (United States)

Genevois, Cyril; Berthier, Philippe; Guidou, Vincent; Muller, Franck; Thiebault, Boris; Rogowski, Isabelle

2014-11-01

In women's handball, the large numbers of throws and passes make the shoulder region vulnerable to overuse injuries. Repetitive throwing motions generate imbalance between shoulder internal- and external-rotator muscles. It has not yet been established whether sling-based training can improve shoulder external-rotator muscle strength. This study investigated the effectiveness of a 6-wk strengthening program in improving shoulder functional profile in elite female high school handball players. Crossover study. National elite handball training center. 25 elite female high school handball players. The program, completed twice per week for 6 wk, included sling-based strengthening exercises using a suspension trainer for external rotation with scapular retraction and scapular retraction alone. Maximal shoulder external- and internal-rotation strength, shoulder external- and internal-rotation range of motion (ROM), and maximal throwing velocity were assessed preintervention and postintervention for dominant and nondominant sides. After sling training, external- and internal-rotation strength increased significantly for both sides (P ≤ .001, and P = .004, respectively), with the result that there was no significant change in external- and internal-rotation strength ratios for either the dominant or the nondominant shoulder. No significant differences were observed for external-rotation ROM, while internal-rotation ROM decreased moderately, in particular in the dominant shoulder (P = .005). Maximal throwing velocity remained constant for the dominant arm, whereas a significant increase was found for the nondominant arm (P = .017). This 6-wk strengthening program was effective in improving shoulder external-rotator muscle strength but resulted in a decrease in the ROM in shoulder internal rotation, while throwing velocity remained stable. Adding a stretching program to this type of sling-based training program might help avoid potential detrimental effects on shoulder ROM.

Visual Enhancement for Sports Entertainment by Vision-Based Augmented Reality

Directory of Open Access Journals (Sweden)

Hideo Saito

2008-09-01

Full Text Available This paper presents visually enhanced sports entertainment applications: AR Baseball Presentation System and Interactive AR Bowling System. We utilize vision-based augmented reality for getting immersive feeling. First application is an observation system of a virtual baseball game on the tabletop. 3D virtual players are playing a game on a real baseball field model, so that users can observe the game from favorite view points through a handheld monitor with a web camera. Second application is a bowling system which allows users to roll a real ball down a real bowling lane model on the tabletop and knock down virtual pins. The users watch the virtual pins through the monitor. The lane and the ball are also tracked by vision-based tracking. In those applications, we utilize multiple 2D markers distributed at arbitrary positions and directions. Even though the geometrical relationship among the markers is unknown, we can track the camera in very wide area.

Rotator Cuff Injuries.

Science.gov (United States)

Connors, G. Patrick

Many baseball players suffer from shoulder injuries related to the rotator cuff muscles. These injuries may be classified as muscular strain, tendonitis or tenosynovitis, and impingement syndrome. Treatment varies from simple rest to surgery, so it is important to be seen by a physician as soon as possible. In order to prevent these injuries, the…

Monkey Business

Science.gov (United States)

Blackwood, Christine Horvatis

2012-01-01

A ballerina, a gladiator, a camper, a baseball player, a surfer, and a shopper; these are just a few of the amazing monkeys that the author's seventh graders created from papier-mache. This project provided an opportunity for students to express themselves through the creation of sculptural characters based on their own interests, hobbies, and…

New York Newspaper Coverage of Jackie Robinson in His First Major League Season.

Science.gov (United States)

Washburn, Pat

Sports articles appearing in three New York City newspapers in Jackie Robinson's first season as a major league baseball player were examined to determine if there was biased reporting based on racial prejudice. The sports pages of the New York "Times," the "Herald Tribune," and the "Daily News" for 44 days in 1947…

Inequity and vulnerability to dropout symptoms : An exploratory causal analysis among highly skilled youth soccer players

NARCIS (Netherlands)

Van Yperen, N.W.

This study investigated whether the perception of disadvantageous inequity makes athletes more vulnerable to dropping out. Sixty five talented youth male soccer players (mean age = 16.6 years), attending a prestigious soccer school, completed a questionnaire at the beginning and at the end of the

[Dietary behaviours of volleyball and basketball players].

Science.gov (United States)

Szczepańska, Elzbieta; Spałkowska, Agnieszka

2012-01-01

In sports, such as basketball and volleyball, players must demonstrate the speed, strength, stamina and concentration. Correct nutrition affects the strength of the muscles and the extension of capacity. It is also necessary for the proper functioning of the nervous system and determines the rate of regeneration after physical effort. The aim of this study was to assess dietary behaviours of professional volleyball and basketball players and compare the prevalence of correct behaviours in both groups. 209 professional volleyball and basketball players from sports clubs localized in six Silesian cities were survived with the mean of author questionnaire. The chi-square test was used to examine differences in the prevalence of the correct behaviours among players. Analysis of the results obtained showed that 52% of the players had 4-5 meals a day. 35% of respondents had wholemeal bread and/or groats daily. Milk and dairy products daily ate 71% of surveyed players, meat and sausages 70% respectively. 41% of respondents had cottage cheese and 28% had fish several times a week. Vegetables and fruit were eaten by 21% and respectively 23% of respondents. Sweets were eaten daily by 40% of surveyed, while fast-food were eaten several times a week by 17% of players. Nutrients for athletes were used by 32%, and vitamin supplementation by 48% of respondents. Prevalence of correct dietary behaviour in the group of professional volleyball and basketball players differed. Basketball players statistically more frequently than volleyball players had 4-5 meals a day, had wholemeal bread and/or thick groats, milk and dairy products, meat and sausages, especially poultry. They had raw vegetables and fruit several times a day. They drank more than 2.5 liters of fluids per day. They also significantly more frequently than volleyball players consumed the fast-food occasionally or never. Dietary behaviours of surveyed players were incorrect. Comparison of prevalence of proper behaviours

Chess players' fame versus their merit.

Science.gov (United States)

Simkin, M V; Roychowdhury, V P

2015-12-12

We investigate a pool of international chess title holders born between 1901 and 1943. Using Elo ratings, we compute for every player his expected score in a game with a randomly selected player from the pool. We use this figure as the player's merit. We measure players' fame as the number of Google hits. The correlation between fame and merit is 0.38. At the same time, the correlation between the logarithm of fame and merit is 0.61. This suggests that fame grows exponentially with merit.

Racism in soccer? Perception of challenges of black and white players by white referees, soccer players, and fans.

Science.gov (United States)

Wagner-Egger, Pascal; Gygax, Pascal; Ribordy, Farfalla

2012-02-01

This experiment investigated challenge evaluations in soccer and their relation to prejudice: more precisely, whether skin colour may influence judgments of soccer tackles. Three groups of participants (soccer players, referees,and soccer fans) were asked to evaluate challenges, featuring Black and White players as aggressors and victims in a mixed-design study. Results showed that participants made some differentiations between Black and White players in a challenge evaluation task. Participants were more likely to consider within-group challenges as fouls and were faster to consider challenges made by Black players as fouls. On the other hand, fouls made by White players were seen as more severe. There were no major differences between the participating groups, suggesting that the observed effects were independent of how good players were or whether the participants were referees or not.

DIFFERENCES IN FUNCTIONAL AND MOTOR ABILITIES OFYOUNG FOOTBALL PLAYERS, BASKETBALL AND VOLLEYBALL PLAYERS

Directory of Open Access Journals (Sweden)

Franja Fratrić

2009-11-01

Full Text Available The main goal of this research is to determine whether and what differences exist between the three groups of subjects (high-quality football, volleyball and basketball cadets and youth age, in the motoric and functional abilities, as well as to identify dif- ferences between subgroups within each sport. The sample consists of 61 volleyball, 31 basketball player and football player 31 (total n = 123 male, cadet and youth age are members of local clubs. Subjects were born between 01.01.1991 and 12.12.1994. The sample of variables are the values of 17 tests for the evaluation of functional and mobile status. The Motor-functional status on the basis of the results of secondary value of foot- ball, basketball and volleyball make a clear conclusion that the football players showed the best results in almost all the tests and that they had the smallest disbalance in the power of certain groups of muscles.The football players hve the highest homogeneity.

Chess in Schools: Evaluation Report and Executive Summary

Science.gov (United States)

Jerrim, John; Macmillan, Lindsey; Micklewright, John; Sawtell, Mary; Wiggins, Meg

2016-01-01

Chess in Primary Schools is a whole-school approach to teaching primary school children how to play chess. Children take 30 hours of chess lessons delivered by a tutor who is an experienced chess player, and the school is given the option to set up a chess club as a lunchtime or after-school activity. Chess classes are delivered during the school…

Comparative characteristics of psychophysiological features skilled basketball players-women with hearing and skilled basketball players healthy

Directory of Open Access Journals (Sweden)

Kozina Zh.L.

2013-06-01

Full Text Available A comparative analysis of the psychophysiological features of skilled basketball players with normal hearing and impaired hearing aid. The study involved two women's basketball team to 12 people each. The study used a complex computer psychodiagnosis. The complex includes 20 psychophysiological and 18 personal psychological tests. The indicators of the time simple and complex reaction and average tapping test healthy skilled basketball players and basketball players are hearing impaired. There was a significant higher rates of visual-motor speed and reaction-tapping test in basketball players with hearing compared to healthy athletes. This is explained by compensatory mechanisms that occur in connection with the violation of the audition.

Comparative characteristics of psychophysiological features skilled basketball players-women with hearing and skilled basketball players healthy

Directory of Open Access Journals (Sweden)

Zh.L. Kozina

2013-07-01

Full Text Available A comparative analysis of the psychophysiological features of skilled basketball players with normal hearing and impaired hearing aid. The study involved two women's basketball team to 12 people each. The study used a complex computer psychodiagnosis. The complex includes 20 psychophysiological and 18 personal psychological tests. The indicators of the time simple and complex reaction and average tapping test healthy skilled basketball players and basketball players are hearing impaired. There was a significant higher rates of visual-motor speed and reaction-tapping test in basketball players with hearing compared to healthy athletes. This is explained by compensatory mechanisms that occur in connection with the violation of the audition.

Student Learning through Hands-On Industry Projects

Science.gov (United States)

Acheson, Lingma Lu

2014-01-01

Learning is most effective when accompanied by doing. If someone desires to become a baseball player, being told how to play the game, watching others play and even understanding the rules of the game are mostly ineffective if the individual never "swings the bat". This paper outlines the implementation of this method (swinging the bat)…

Globalization, Foreign Languages and National Identity

Science.gov (United States)

Tavarez DaCosta, Pedro

2018-01-01

Due to the fact of the transformation of the Dominican economy, jumping from a rural, sugar cane exporting-country to a more diverse economy, based in four pillars: The Remittance of US Dollars of Dominicans living in America, the Tourism Industry, the Duty-free Industrial Parks and the Major League Base-ball Players and Academies, it is not…

The consultation of rugby players in co-developing a player health study: feasibility and consequences of sports participants as research partners.

Science.gov (United States)

Davies, Madeleine A M; Balai, Edward; Adams, Jo; Carter, John-Henry; Judge, Andrew; Newton, Julia L; Arden, Nigel K

2017-01-01

Many funding bodies within the United Kingdom and globally have encouraged public involvement in research. The Department of Health has also called public involvement a sign of good research. Despite the wide acceptance of public involvement improving many aspects of research, from its design to its communication, involvement has varied levels of implementation across different fields of research. Sports people have rarely been involved in research, partly as this research tends not to be funded by mainstream funding bodies. This may lead to a lower research quality, not founded in player ('service user') experiences. When creating a study of former rugby player health, we were very keen to involve rugby players, understand their thoughts on player health, and their playing experiences. This article explains how rugby players were involved in several ways, but mainly in group discussions during the design stage. These groups helped to inform our study's aims and questionnaire, ensure the questionnaire would capture player experiences and answer questions relevant to players, that they would like to understand after their participation in rugby. We found that these groups were easy to arrange, and that in only one session with each group, we were given many ideas of how to improve the questionnaire and study. We believe that other studies in sports should involve sports people, and that this is a useful activity that will change data collection forms and processes, improving the research, helping researchers, and making studies more suitable for players who take part in them. Background Patient and public involvement ('involvement') in the UK has increased in accordance with funding requirements, patient-centered health policy initiatives and reporting of the positive impact of involvement for those involved, research and researchers. However, involvement has not been implemented equally across all disease areas and populations. The aim of this process was to

Leadership Preferences of Adolescent Players in Sport: Influence of Coach Gender.

Science.gov (United States)

Cruz, Angelita B; Kim, Hyun-Duck

2017-06-01

The authors investigated the coaching behavior preferences and the relationships of these preferences with variables such as gender, type of sport, playing experience, competitive level, and coach gender among young athletes in the national badminton league. Participants were 167 elementary and high school badminton players (91 girls and 76 boys; age range = 9-18 years; M = 13.5 (SD = 2.22) years) competing in the badminton event of a national league. Players' preferences for coaching behavior were measured using athlete preference version of the LSS to evaluate the five dimensions of leadership behavior in a sporting context. Notably, young athletes strongly preferred training and instruction, followed by positive feedback, democratic behavior, social support, and autocratic behavior. An interaction effect of athlete and coach gender on the leadership dimensions of democratic behavior, autocratic behavior, and social support was found. Male athletes with female coaches preferred more democratic behavior, autocratic behavior, and social support behavior than did those with male coaches. Conversely, female players with male coaches favored more democratic behavior, autocratic behavior, and social support than did those with female coaches. This study provides valuable insight into understanding the dynamics of sport leadership environments among young athletes, and how crucial is the role of coach's gender in the athlete-coach dyad interaction.

The 1984 ARI Survey of Army Recruits: User’s Manual

Science.gov (United States)

1986-05-01

take and pass in high school? 93. Major league baseball playoffs 94. World Series (Mark all that apply) 95. NBA basketball A. Elementary Algebra B. Plane...regular G. On a farm or ranch season games 105. Major league baseball playoffs 106. World Series 116. Which of the following mathematics 107. NBA ... basketball and technical courses, if any, did you take and pass in high school? 108. College basketball ( 109. NHL hockey A. Elementary Algebra 110

THE TRANSFORMATIONAL PROCESSES INVOLVING MOTOR SKILLS THAT OCCUR UNDER THE INFLUENCE OF BASIC PRELIMINARY TRAINING IN YOUNG HANDBALL PLAYERS

Directory of Open Access Journals (Sweden)

Markovic Sasa

2011-06-01

Full Text Available The population from which we extracted a sample of 76 subjects consisted of elementary school students in Kursumlija, all male, aged 12-13, who were divided into a sub-sample consisting of 38 young handball players who took part in the training sessions of a school of handball and another sub-sample consisting of 38 non-athletes, who only took part in their regular physical education classes. The aim of the research was to determine the transformation processes involving motor skills, which occur under the influence of basic preliminary training in young handball players. The subject matter of the study was to examine whether a statistically significant increase in the level of motor skills would occur under the influence of physical exercise as part of basic preliminary training in the final as compared to the initial state. Six motor tests which define the dimensions of explosive and repetitive strength were used. The results of the research indicate that significant transformational processes involving the motor skills of young handball players occurred in the final as compared to the initial measuring, under the influence of basic preliminary training.

Rules of engagement : influence of co-player presence on player involvement in digital games

NARCIS (Netherlands)

Gajadhar, B.J.; Kort, de Y.A.W.; IJsselsteijn, W.A.

2009-01-01

This article presents an empirical study of social setting as a determinant of player involvement in competitive play. We conceptualize player experience as comprising of components of involvement and enjoyment. Involvement relates to the attentional pull of games encompassing feelings of immersion,

An embouchure aid for saxophone player

Directory of Open Access Journals (Sweden)

Ho-Jin Moon

2012-02-01

Full Text Available This study aims to introduce the method that can relieve vibrating forces to oral environment by making an embouchure aid. Thin plastic crown forms were fabricated to prevent tooth abrasion and irritation to lip mucosa for the saxophone player. After application to the player, the most comfort form was chosen and delivered to 3 professional saxophone players. After 5 mon, the players responded to the survey. This embouchure aid did not disturb playing and gave comfort to lower lip. In general, the players preferred thin soft type and thought it caused little effect on sound. Far too little attention has been paid to the problems encountered by single-reed wind instrumentalist who suffer from tooth abrasion and irritation to lip mucosa. The embouchure aid not only prevent tooth damage but also diminish the discomfort of tight embouchure.

Auditory memory function in expert chess players.

Science.gov (United States)

Fattahi, Fariba; Geshani, Ahmad; Jafari, Zahra; Jalaie, Shohreh; Salman Mahini, Mona

2015-01-01

Chess is a game that involves many aspects of high level cognition such as memory, attention, focus and problem solving. Long term practice of chess can improve cognition performances and behavioral skills. Auditory memory, as a kind of memory, can be influenced by strengthening processes following long term chess playing like other behavioral skills because of common processing pathways in the brain. The purpose of this study was to evaluate the auditory memory function of expert chess players using the Persian version of dichotic auditory-verbal memory test. The Persian version of dichotic auditory-verbal memory test was performed for 30 expert chess players aged 20-35 years and 30 non chess players who were matched by different conditions; the participants in both groups were randomly selected. The performance of the two groups was compared by independent samples t-test using SPSS version 21. The mean score of dichotic auditory-verbal memory test between the two groups, expert chess players and non-chess players, revealed a significant difference (p≤ 0.001). The difference between the ears scores for expert chess players (p= 0.023) and non-chess players (p= 0.013) was significant. Gender had no effect on the test results. Auditory memory function in expert chess players was significantly better compared to non-chess players. It seems that increased auditory memory function is related to strengthening cognitive performances due to playing chess for a long time.

Forty days of free school meals as a tool for introducing market-based healthy school meal systems in 35 Danish schools

DEFF Research Database (Denmark)

Brinck, Nenna Maria; Hansen, Mette Weinreich; Kristensen, Niels Heine

2011-01-01

-start the implementation of healthy school meal systems in Danish schools. This paper argues that the initiative (in reality) invited the establishment of a service system concept, which dominated the initiative and led to a lack of involvement of important key players needed in health promotion. Methods: The method used...... for data collection was semi-structured, qualitative interviews. Results: The main results from a systematic examination of the 35 participating schools show that the systems were mainly organized with external suppliers, and only a few of the 35 schools succeeded in establishing a user-paid school meal...... for achieving the goal of establishing new, healthy and user-paid school meals....

Effect Of Plyometric Training On Vertical Jump Performance And Neuromuscular Adaptation In Volleyball Player

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Dara Hosseini

2012-12-01

Full Text Available The purpose of this study was to examine the effectiveness of 12-week plyometric training on vertical jump performance (Vj, maximal surface EMG, M-wave amplitude, M�wave latency, and nerve conduction velocity (NCV in men volleyball player. Thirty junior high school volleyball players' volunteers (age: 17.53� 0.74; Height: 177.67� 3.14; Weight: 61.31 � 5.32 were divided into plyometric training [PT] (n=15 and control group[c] (n=15. PT group trained so.w' but C group didn't participate in this training. Both groups were pre- and post tested in EMG, M-wave parameters, NCV and Vj test. Tow way ANOVA (group*time interaction and Bonferroni post hoes test demonstrated significant differences (P

Player Skill Decomposition in Multiplayer Online Battle Arenas

OpenAIRE

Chen, Zhengxing; Sun, Yizhou; El-nasr, Magy Seif; Nguyen, Truong-Huy D.

2017-01-01

Successful analysis of player skills in video games has important impacts on the process of enhancing player experience without undermining their continuous skill development. Moreover, player skill analysis becomes more intriguing in team-based video games because such form of study can help discover useful factors in effective team formation. In this paper, we consider the problem of skill decomposition in MOBA (MultiPlayer Online Battle Arena) games, with the goal to understand what player...

Trends in the Presentation, Management, and Outcomes of Little League Shoulder.

Science.gov (United States)

Heyworth, Benton E; Kramer, Dennis E; Martin, Daniel J; Micheli, Lyle J; Kocher, Mininder S; Bae, Donald S

2016-06-01

With rising participation in youth sports such as baseball, proximal humeral epiphysiolysis, or Little League shoulder (LLS), is being seen with increasing frequency. However, there remains a paucity of literature regarding the causes, natural history, or treatment outcomes of LLS. To analyze the demographic, clinical, and diagnostic features of a population of LLS patients, with an emphasis on identifying underlying risk factors for the development and recurrence of LLS after nonoperative treatment. Case series; Level of evidence, 4. A departmental database at a high-volume regional children's hospital was queried to identify cases of LLS between 1999 and 2013. Medical records were reviewed to allow for analysis of age, sex, athletic information, physical examination and radiologic findings, treatment details, clinical course, and rates of recurrence. Ninety-five patients (93 males, 2 females; mean age, 13.1 years; range, 8-16 years) were diagnosed with LLS. The number of diagnosed cases increased annually over the study period. All patients had shoulder pain with overhead athletics; secondary symptoms included elbow pain in 13%, shoulder fatigue or weakness in 10%, and mechanical symptoms in 8%. While the majority of patients (97%) were baseball players (86% pitchers, 8% catchers, 7% other positions), a small subset (3%) were tennis players. On physical examination, 30% were reported to have glenohumeral internal rotation deficit (GIRD), defined as a decreased arc of rotational range of motion of the shoulder. Treatment recommendations included rest in 99% of cases, physical therapy in 79% (including 100% of patients with GIRD), and position change upon return to play in 26%. Average time to full resolution of symptoms was 2.6 months, while average time to return to competition was 4.2 months. Recurrent symptoms were reported in 7% of the overall cohort at a mean of 7.6 months after initial diagnosis. The odds of recurrence in the group with diagnosed GIRD (14

Evaluating Postural Control and Ankle Laxity Between Taping and High-Top Cleats in High School Football Players.

Science.gov (United States)

Pizac, Douglas A; Swanik, Charles B; Glutting, Joseph J; Kaminski, Thomas W

2018-03-01

Lateral ankle sprains are the most common injuries in high school sports. While ankle taping is a preferred method of external prophylactic support, its restrictive properties decline during exercise. The Under Armour ® Highlight cleat is marketed on the premise that it provides added support without the need for additional ankle taping. To determine if differences in ankle joint laxity and postural control exist between football players wearing the Under Armour ® Highlight cleat (Under Armour Inc, Baltimore, MD) as compared to a low/mid-top cleat with ankle tape. Crossover trial. Athletic training room and football practice field sideline. 32 interscholastic football players (15.8 ± 1.0 y; 178.9 ± 7.4 cm; 87.1 ± 21.4 kg). Ankle laxity was assessed using an instrumented ankle arthrometer (Blue Bay Research Inc, Milton, FL), while postural control testing was performed on the Tekscan MobileMat™ Balanced Error Scoring System (BESS; South Boston, MA). The 2 treatments included Under Armour ® Highlight cleats and a low/mid-top cleat with ankle tape applied to the nondominant ankle only. Measurements were taken before and immediately after practice. The independent variable was treatment (Highlight vs low/mid-top cleat with ankle tape). Dependent variables included ankle arthrometry measures of anterior displacement (mm), inversion/eversion rotation (deg), and the modified BESS error scores. A linear mixed-effects model was used for analysis. The low/mid-top cleat with tape condition had significantly higher inversion range-of-motion (ROM) and inversion/eversion rotation postexercise when compared to the Highlight cleat (P Under Armour ® Highlight cleat restricts ankle ROM following a training session better than the taped low/mid-top cleat. Further study is warranted to determine if this high-top style of football cleat can reduce the incidence of ankle sprains and how it might compare to spat taping.

COMPARISON OF MOTOR ABILITIES OF YOUTH FOOTBALL PLAYERS AND PRIMARY SCHOOL PUPILS

OpenAIRE

Miroslav Smajić; Dejan Javorac; Slavko Molnar; Aleksandar Huba Barašić; Bogdan Tomić

2014-01-01

Introduction: Football as a complete sport that is rich in a wide variety of possible movements classified in polistructural, sports complex. To be a football player was able to perform tasks football has, among other things, and have the necessary level of motor abilities that can be achieved only through systematic implementation of training physical training. The aim of this research was to determine the differences in some of the motor abilities between the two researched groups. Methods:...

Identification af explosive power factors as predictors of player quality in young female volleyball players.

Science.gov (United States)

Grgantov, Zoran; Milić, Mirjana; Katić, Ratko

2013-05-01

With the purpose of determining the factor structure of explosive power, as well as the influence of each factor on situational efficiency, 56 young female volleyball players were tested using 14 tests for assessing nonspecific and specific explosive power. By factor analysis, 4 significant factors were isolated which explained the total of over 80% of the common variability in young female volleyball players. The first factor was defined as volleyball-specific jumping, the second factor as nonspecific jumping and sprinting, the third factor as throwing explosive power, while the fourth factor was interpreted as volleyball-specific throwing and spiking speed from the ground. Results obtained by regression analysis in the latent space of explosive power indicate that the identified factors are good predictors of player quality in young female volleyball players. The fourth factor defined as throwing and spiking speed from the ground had the largest influence on player quality, followed by volleyball-specific jumping and nonspecific jumping and sprinting, and to a much lesser extent, by throwing explosive power The results obtained in this age group bring to the fore the ability of spiking and serving a ball of high speed, which hinders the opponents from playing those balls in serve reception and field defence. This ability, combined with a high standing vertical jump reach and spike approach vertical jump reach (which is the basis of the 1st varimax factor) enables successful performance of all volleyball elements by which points are won in complex 1 (spike) and complex 2 (serve and block). Even though the 2nd factor (nonspecific jumping and sprinting) has a slightly smaller impact on situational efficiency in young players, this ability provides preconditions i.e. preparation for successful realisation of all volleyball elements, so greater attention must be paid to perfecting it in young female volleyball players.

A developmental and psychoeducational approach to reducing conflict and abuse in little league and youth sports. The sport psychiatrist's role.

Science.gov (United States)

Kamm, R L

1998-10-01

: Draft Model 1 Public tryouts Previous year rating Coach makes selections Can be very competitive, lacking in "character" Can result in very unequal teams Draft Model 2 Player evaluations placed into a data base Properly programmed computer projects equal teams Draft Model 3 All names placed on a blackboard Relative merits of players discussed Equal team drawn up and placed into a hat Adjustments can be made for coach's child If practical, this author suggests that coaches not pick a name for the team until the first team meeting or practice, when that task can be given to the children. In a symbolic way, this returns some of the sport to them while encouraging social interaction among new teammates, and helping the coach detect who the leaders are. Names of professional teams in the major sports, especially baseball, are to be avoided, as they fuel longstanding unconscious associations and fantasies, and may subtly tilt all participants toward the professional "win at all costs" mentality. No one draft model is perfect for every town, and even the most ethical attempt to achieve balance among teams can be severely tested by parents who request that their athlete be placed on the same team as another child for social or car pool reasons. Such requests are not inviolate, however. For example, they do not usually dictate placement in school classes, and car pools are frequently disrupted when children, in individual sports such as Tae Kwan Do, reach different ability levels, and so attend practices at different times. Baseball is no longer the national pasttime and, as we approach the millennium, American children have too many other attractive, competing interests and time demands to spontaneously organize a pick-up game. One coach shared with the author that his saddest moment in CAP League came when he arrived at 6 PM at a field that had been "reserved" for his team, and found a group of boys who were playing a pick-up game. The coach's impulse was to set his boys fre

Executive Functioning in Highly Talented Soccer Players

Science.gov (United States)

Verburgh, Lot; Scherder, Erik J. A.; van Lange, Paul A.M.; Oosterlaan, Jaap

2014-01-01

Executive functions might be important for successful performance in sports, particularly in team sports requiring quick anticipation and adaptation to continuously changing situations in the field. The executive functions motor inhibition, attention and visuospatial working memory were examined in highly talented soccer players. Eighty-four highly talented youth soccer players (mean age 11.9), and forty-two age-matched amateur soccer players (mean age 11.8) in the age range 8 to 16 years performed a Stop Signal task (motor inhibition), the Attention Network Test (alerting, orienting, and executive attention) and a visuospatial working memory task. The highly talented soccer players followed the talent development program of the youth academy of a professional soccer club and played at the highest national soccer competition for their age. The amateur soccer players played at a regular soccer club in the same geographical region as the highly talented soccer players and play in a regular regional soccer competition. Group differences were tested using analyses of variance. The highly talented group showed superior motor inhibition as measured by stop signal reaction time (SSRT) on the Stop Signal task and a larger alerting effect on the Attention Network Test, indicating an enhanced ability to attain and maintain an alert state. No group differences were found for orienting and executive attention and visuospatial working memory. A logistic regression model with group (highly talented or amateur) as dependent variable and executive function measures that significantly distinguished between groups as predictors showed that these measures differentiated highly talented soccer players from amateur soccer players with 89% accuracy. Highly talented youth soccer players outperform youth amateur players on suppressing ongoing motor responses and on the ability to attain and maintain an alert state; both may be essential for success in soccer. PMID:24632735

Executive functioning in highly talented soccer players.

Directory of Open Access Journals (Sweden)

Lot Verburgh

Full Text Available Executive functions might be important for successful performance in sports, particularly in team sports requiring quick anticipation and adaptation to continuously changing situations in the field. The executive functions motor inhibition, attention and visuospatial working memory were examined in highly talented soccer players. Eighty-four highly talented youth soccer players (mean age 11.9, and forty-two age-matched amateur soccer players (mean age 11.8 in the age range 8 to 16 years performed a Stop Signal task (motor inhibition, the Attention Network Test (alerting, orienting, and executive attention and a visuospatial working memory task. The highly talented soccer players followed the talent development program of the youth academy of a professional soccer club and played at the highest national soccer competition for their age. The amateur soccer players played at a regular soccer club in the same geographical region as the highly talented soccer players and play in a regular regional soccer competition. Group differences were tested using analyses of variance. The highly talented group showed superior motor inhibition as measured by stop signal reaction time (SSRT on the Stop Signal task and a larger alerting effect on the Attention Network Test, indicating an enhanced ability to attain and maintain an alert state. No group differences were found for orienting and executive attention and visuospatial working memory. A logistic regression model with group (highly talented or amateur as dependent variable and executive function measures that significantly distinguished between groups as predictors showed that these measures differentiated highly talented soccer players from amateur soccer players with 89% accuracy. Highly talented youth soccer players outperform youth amateur players on suppressing ongoing motor responses and on the ability to attain and maintain an alert state; both may be essential for success in soccer.

Unusual stress fracture in an adolescent baseball pitcher affecting the trochlear groove of the olecranon

International Nuclear Information System (INIS)

Blake, Joseph J.; Block, John J.; Kan, J.H.; Hannah, Gene A.

2008-01-01

Stress fractures of the proximal ulna are known to occur in throwing athletes. Most cases extend to involve the olecranon, and cases limited to the trochlear groove are rare. In this report we present a 17-year-old elite baseball pitcher with a stress fracture of the trochlear groove of the proximal ulna. Diagnosis was made by demonstration of characteristic signal changes on MRI of the elbow. The fracture occurred at the cortical notch, also known as the pseudodefect of the trochlear groove. This case suggests that the cortical notch serves as an area of weakness predisposing pitchers to development of a stress fracture. (orig.)

Countermovement jump height: gender and sport-specific differences in the force-time variables.

Science.gov (United States)

Laffaye, Guillaume; Wagner, Phillip P; Tombleson, Tom I L

2014-04-01

The goal of this study was to assess (a) the eccentric rate of force development, the concentric force, and selected time variables on vertical performance during countermovement jump, (b) the existence of gender differences in these variables, and (c) the sport-specific differences. The sample was composed of 189 males and 84 females, all elite athletes involved in college and professional sports (primarily football, basketball, baseball, and volleyball). The subjects performed a series of 6 countermovement jumps on a force plate (500 Hz). Average eccentric rate of force development (ECC-RFD), total time (TIME), eccentric time (ECC-T), Ratio between eccentric and total time (ECC-T:T) and average force (CON-F) were extracted from force-time curves and the vertical jumping performance, measured by impulse momentum. Results show that CON-F (r = 0.57; p differ between both sexes (p differ, showing a similar temporal structure. The best way to jump high is to increase CON-F and ECC-RFD thus minimizing the ECC-T. Principal component analysis (PCA) accounted for 76.8% of the JH variance and revealed that JH is predicted by a temporal and a force component. Furthermore, the PCA comparison made among athletes revealed sport-specific signatures: volleyball players revealed a temporal-prevailing profile, a weak-force with large ECC-T:T for basketball players and explosive and powerful profiles for football and baseball players.

CHANGES IN DEVELOPMENT OF EHPLOSIVE POWER OF LEGS UNDER THE INFLUENCE OF PLYOMETRIC TRAINING METHOD BY VOLLEYBALL PLAYERS

Directory of Open Access Journals (Sweden)

Vladan Milić

2009-11-01

Full Text Available With goal to examine effects of plyometric training program on development of jumping strength for volleyball players, it was organized an experimental research on pattern of 23 volleyball players from cadet team and 23 students from high-school. For needs of this research four tests are valid for estimation, jump in block with left and right leg and jump in spike with left and right leg. Experiment has been realized in the second part on conditional preparations, and lasted for six weeks with two or three trainings per week. Control group had physical education lessons at their schools twice a week. On the results of research and discussion we can say that the model of training we used for development of jumping as a basic factor in experimental group brought statistically bigger difference in improving jumping that it brought in control group.

Causes of financial mismanagement in South African public schools ...

African Journals Online (AJOL)

This paper investigates the underlying causes of financial mismanagement in public schools and focuses on the perceptions of various role players in the Limpopo Province of South Africa. The various Departments of Basic Education in South Africa allocate funds to schools each year, and expect school principals and ...

Comparison of Angiotensin Converting Enzyme (ACE gene polymorphisms elite basketball players and volleyball players

Directory of Open Access Journals (Sweden)

Emin Süel

2015-09-01

Full Text Available Aim: The purpose of this study is to research the differences of genotype polymorphism between the elite male and elite female basketball player, volleyball player and control group. Material and Methods: 58 basketball players (ages 24.25±4.99 years, height 188.22±12.31 cm and weight 80.62±16.34 kg, 64 volleyball players (ages 22.82±5.40 years, height 188.67±9.69 cm and weight 77.82±12.14 kg and 122 sedentary subjects (control group were participated randomly in the study. 5cc blood was taken control and control groups for measuring the ACE gene polymorphism. Chi-square and analysis of variance (ANOVA, Levene’s Tests, and frequencies of allele were used for statistical evaluation at significance level p0.05, basketball, volleyball and control group (p>0.05, male basketball, volleyball and control group (p>0.05, female basketball, volleyball and control group (p>0.05 and male and female athletes (p>0.05 respectively. There were no significance differences in male athletes between the genotype distribution and physical performance tests, such as 20m shuttle-run (F=1.31, vertical jump (F=0.22, and 20m sprint test (F=0.44. There were also no significance differences in female athletes between the genotype distribution and physical performance tests, such as 20m shuttle-run (F=2.03, vertical jump (F=0.10, and 20m sprint test (F=1.17. Conclusion: ACE polymorphism genotype distribution in terms of elite female and male volleyball players with elite female and male basketball players are the same.

Final Environmental Assessment Nellis Air Force Base School Initiative, Nellis Air Force Base, Clark County, Nevada

Science.gov (United States)

2015-04-01

by baseball and softball fields. Optional Site 4 is not developed and is an area that has been set aside in the on-bas~ housing development as a...site consists of approximately 3 acres located on the west side of the Youth Center and currently contains a softball field (Photograph 2-2; Figure 2-1...The softball field would be removed to allow for construction of the new school. Photograph 2-1. Optional Site 1 Photograph 2-2. Optional Site 2

Psychological Gender and Emotional Intelligence in Youth Female Soccer Players

Directory of Open Access Journals (Sweden)

Rutkowska Katarzyna

2015-09-01

Full Text Available Many sports (for instance soccer are stereotypically perceived as a male activity. Even so, more and more women decide to become competitive athletes. Since the theory of sport requires comprehensive explanations and the practice of sport needs clear guidelines, interdisciplinary studies into the nature of sport, including its psychological aspects, are necessary. Analysing the psychological profile of female soccer players, particularly those who are about to become professional athletes, can provide many interesting insights into the specific character of female youth sport and show where improvements can be made in athletic training programmes (especially in mental training. It is therefore important to study psychological gender that determines social behaviours and to analyse female athletes’ emotional intelligence. Emotional intelligence is defined as a set of emotional competencies that determine the effectiveness of human behaviours. Psychological gender and emotional intelligence have a significant effect on human adaptability and the efficiency of psychosocial functioning. This research was undertaken with the dual purpose of identifying the psychological gender and emotional intelligence of female soccer players. It involved 54 secondary-school girls, some of whom attended a sports class and others played on the Polish national team. The following tools were used to carry out the research: the Gender Assessment Inventory (IPP [This and the other acronyms derive from the Polish language]-developed by Kuczyńska and the Emotional Intelligence Questionnaire (INTE; created by Jaworowska and Matczak. As shown by the analysis of the results, most female soccer players in the study were androgynous and the level of their emotional intelligence was significantly higher than in other participants. This also seems to point to their significantly greater adaptability. At the same time, the level of emotional intelligence in many players was

Psychological Gender and Emotional Intelligence in Youth Female Soccer Players.

Science.gov (United States)

Rutkowska, Katarzyna; Bergier, Józef

2015-09-29

Many sports (for instance soccer) are stereotypically perceived as a male activity. Even so, more and more women decide to become competitive athletes. Since the theory of sport requires comprehensive explanations and the practice of sport needs clear guidelines, interdisciplinary studies into the nature of sport, including its psychological aspects, are necessary. Analysing the psychological profile of female soccer players, particularly those who are about to become professional athletes, can provide many interesting insights into the specific character of female youth sport and show where improvements can be made in athletic training programmes (especially in mental training). It is therefore important to study psychological gender that determines social behaviours and to analyse female athletes' emotional intelligence. Emotional intelligence is defined as a set of emotional competencies that determine the effectiveness of human behaviours. Psychological gender and emotional intelligence have a significant effect on human adaptability and the efficiency of psychosocial functioning. This research was undertaken with the dual purpose of identifying the psychological gender and emotional intelligence of female soccer players. It involved 54 secondary-school girls, some of whom attended a sports class and others played on the Polish national team. The following tools were used to carry out the research: the Gender Assessment Inventory (IPP [This and the other acronyms derive from the Polish language]-developed by Kuczyńska) and the Emotional Intelligence Questionnaire (INTE; created by Jaworowska and Matczak). As shown by the analysis of the results, most female soccer players in the study were androgynous and the level of their emotional intelligence was significantly higher than in other participants. This also seems to point to their significantly greater adaptability. At the same time, the level of emotional intelligence in many players was average or low

Local contextual processing of abstract and meaningful real-life images in professional athletes.

Science.gov (United States)

Fogelson, Noa; Fernandez-Del-Olmo, Miguel; Acero, Rafael Martín

2012-05-01

We investigated the effect of abstract versus real-life meaningful images from sports on local contextual processing in two groups of professional athletes. Local context was defined as the occurrence of a short predictive series of stimuli occurring before delivery of a target event. EEG was recorded in 10 professional basketball players and 9 professional athletes of individual sports during three sessions. In each session, a different set of visual stimuli were presented: triangles facing left, up, right, or down; four images of a basketball player throwing a ball; four images of a baseball player pitching a baseball. Stimuli consisted of 15 % targets and 85 % of equal numbers of three types of standards. Recording blocks consisted of targets preceded by randomized sequences of standards and by sequences including a predictive sequence signaling the occurrence of a subsequent target event. Subjects pressed a button in response to targets. In all three sessions, reaction times and peak P3b latencies were shorter for predicted targets compared with random targets, the last most informative stimulus of the predictive sequence induced a robust P3b, and N2 amplitude was larger for random targets compared with predicted targets. P3b and N2 peak amplitudes were larger in the professional basketball group in comparison with professional athletes of individual sports, across the three sessions. The findings of this study suggest that local contextual information is processed similarly for abstract and for meaningful images and that professional basketball players seem to allocate more attentional resources in the processing of these visual stimuli.

Translucent Players: Explaining Cooperative Behavior in Social Dilemmas

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Valerio Capraro

2016-06-01

Full Text Available In the last few decades, numerous experiments have shown that humans do not always behave so as to maximize their material payoff. Cooperative behavior when non-cooperation is a dominant strategy (with respect to the material payoffs is particularly puzzling. Here we propose a novel approach to explain cooperation, assuming what Halpern and Pass call translucent players. Typically, players are assumed to be opaque, in the sense that a deviation by one player in a normal-form game does not affect the strategies used by other players. But a player may believe that if he switches from one strategy to another, the fact that he chooses to switch may be visible to the other players. For example, if he chooses to defect in Prisoner's Dilemma, the other player may sense his guilt. We show that by assuming translucent players, we can recover many of the regularities observed in human behavior in well-studied games such as Prisoner's Dilemma, Traveler's Dilemma, Bertrand Competition, and the Public Goods game.

The audiological health of horn players.

Science.gov (United States)

Wilson, Wayne J; O'Brien, Ian; Bradley, Andrew P

2013-01-01

Among orchestral musicians, horn players are one of the most at-risk groups for noise-induced hearing loss (NIHL). To investigate this group further, pure tone audiometry and a 14-item questionnaire were used to assess the hearing health, as well as attitudes and practices regarding hearing conservation, among 142 French horn players attending an international horn conference in Brisbane, Australia. Of this study's French horn players, 11.1% to 22.2%, and 17.7% to 32.9% of those aged ≤40 years, showed some form of hearing loss (corrected for age and gender) typical of NIHL, using conservative versus lenient criteria, respectively. Stepwise multiple regression analyses showed no obvious predictor of hearing loss in this study's participants. Of the 18% of participants who reported using hearing protection, 81% used this protection "sometimes" and 50% used generic, foam, or other inferior forms of protection. Continued efforts to better manage the hearing health of horn players is warranted particularly as any hearing loss will affect a horn player's ability to perform and therefore his or her livelihood. Managing the hearing health of horn players will be challenging, however, with no simple predictor of NIHL loss being identified in this study's sample.

The Use of Simulation Technology in Sport Finance Courses: The Case of the Oakland A’s Baseball Business Simulator

OpenAIRE

Joris, Drayer; Daniel, Rascher

2007-01-01

Teaching a graduate level sport finance class can be quite complex. With a variety of concepts, such as pricing, budgeting, and public funding, to convey in a limited amount of time, new forms of pedagogy are necessary to assist instructors as this technologically-advanced generation enters into academia. Subsequently, technology has been created to apply basic concepts related to finance to the complexity of a professional sports organization. One such program is the Oakland A’s Baseball ...

The Prevalence of Injuries in Professional Turkish Soccer Players

Science.gov (United States)

Yamaner, Faruk; Gumusdag, Hayrettin; Kartal, Alparslan; Gumus, M.; Gullu, A.; Imamoglu, O.

2011-01-01

Study aim: To assess the prevalence and anatomical sites of injuries in professional soccer players in one game season. Material and methods: A cohort of 510 professional male soccer players consisting of 48 goalkeepers, 194 defence players, 189 mid-field players and 79 forward players of the 1st and 2nd Turkish Professional Soccer Leagues in…

Differences in morphological characteristics between of football pioneer and elementary school pupils

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Javorac Dejan

2015-01-01

Full Text Available For a large number of sports disciplines generally known morphological structure that most influence the sporty performance, although, no doubt, the coefficients of participation of some morphological dimension in the equation specification changes in development techniques and tactics and modern world achievements in a particular sport. It was determined that the anthropological characteristics, each in its own way, the important task of training in solving with football players (Malacko i Radosav 1985. The aim of this research was to determine differences in the morphological characteristics between of football pioneer and elementary school pupils. In a sample of 196 subjects, the average age of 12:45 ± 0.03 years, there was a comparison of morphological characteristics. The first group consisted of 82 players - Pioneers FC 'Red Star' from Belgrade and the other 114 elementary school pupils from Novi Sad. A sample of five measures for the evaluation of morphological characteristics were: body height, body weight, circumference of chest, waist circumference and volume of the thigh. Comparison of morphological characteristics of young soccer players and elementary school pupils was carried out by using multivariate analysis of variance (MANOVA and univariate analysis of variance (ANOVA. Analysis of morphological characteristics of young soccer players and elementary school pupils found that there were no statistically significant differences.

Badminton injuries in youth competitive players.

Science.gov (United States)

Goh, S L; Mokhtar, A H; Mohamad Ali, M R

2013-02-01

The aim of the study was to examine sports injury pattern and establish cost of injuries in relation to training of 58 competitive badminton players in a Malaysian National Sports School. This one-year prospective observational study recruited all the 13-16 year old students after obtaining informed consent from their appointed guardian. All participants were requested to report any injuries, which were pain or disabilities that occur within the study period (September 1, 2008 to August 31, 2009) either during training or competition. Injured students were to seek treatment from the researcher(s) who made weekly visits and they were then followed up accordingly until they return to full training. Details and progress of the injuries were documented during each visit. Sixty-three injuries were recorded. Soft tissue sprains/strains were the commonest injury (64%). About one third of the injuries occurred in the lower limb especially the knees and was followed by back injuries; 38% of the injuries did not require training modification, half of these injuries resumed training within one week. Upon full training, half of them were still symptomatic. Injury risk was 57%; injury rate was 0.9 injuries/ player/1000 training hours. Badminton injuries mostly involved the lower limb and almost all overuse injuries occurred in the lower limb. However, badminton injuries as a whole were predominantly sprains and strains, and not overuse in nature as widely believed.

ANALYSIS AND COMPARISON OF ADOLESCENT ATHLETES' MOTIVATION: BASKETBALL PLAYERS VS. FOOTBALL PLAYERS

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Bartolom\\u00E9 J. Almagro

2009-01-01

Full Text Available The motivation of an athlete is determinant for the athletic engagement of the adolescent. The present study attempts to analyze the motivation of adolescent basketball and football players from the perspectives of Achievement Goal Theory (Nicholls, 1989 and Self-Determination Theory (Deci & Ryan, 1985. The study's sample was composed of 248 athletes from 12 to 17 years of age. Half were from basketball and half were from football. The instruments that were utilized were: the Spanish version of the Sport Motivation Scale (SMS (Núñez, Martín-Albo, Navarro, & González, 2006, the Spanish version of the Perceived Motivational Climate in Sport Questionnaire-2 (PMSCQ-2 (Balaguer, Mayo, Atienza, & Duda, 1997, and the adapted Spanish translation (Moreno, Moreno, & Cervelló, 2007 of the Intention to be Physically Active Scale (IPAS by Hein, Müür, and Koka (2004. The comparison of the means of the variables between football and basketball players was done utilizing the student t-test for independent samples. Significant differences were found for variables such as: intrinsic motivation (IM toward accomplishment, external regulation, amotivation, task, ego, and Self-Determination Index (SDI. Basketball players obtained higher values in the SDI, in task, and in IM toward accomplishment than football players. The search for premature performance in football and coaches' educations can help to explain these differences. The importance of these differences reside in the relationship between these motivational variables and the adherence to athletic practice. In conclusion, basketball demonstrated better values in motivational variables, which demonstrates that training sessions are more oriented toward task than ego, that players have more intrinsic and self-determined motivation, and therefore, the adherence of the young athletes will be greater in this sport.

VOLUME OF PHYSICAL ACTIVITY AND INJURY OCCURRENCE IN YOUNG BASKETBALL PLAYERS

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Jenny Gianoudis

2008-03-01

Full Text Available Participation in organised, competitive physical activity by young athletes is increasing rapidly. This is concurrent with an increase in sporting injuries in the young population. This pilot study aimed to compare the weekly volume and types of physical activity in young basketball players injured and not injured during the season. Detailed physical activity and injury data were prospectively collected in 46 school-level basketball players aged 14 to 18 years. Participants completed physical activity logs which documented the type of physical activity undertaken, what the activity consisted of (i.e. training, competition and the level at which it was played on a daily basis. Allied health staff completed a weekly injury form. Results showed that injured and uninjured athletes participated in a similar volume of total weekly physical activity over the season. However, injured athletes (p = 0.04 and athletes who specifically sustained overuse injuries (p = 0.01 participated in a greater amount of basketball refereeing than uninjured athletes. Based on these findings it was concluded that greater participation in running-type physical activity such as refereeing, as an addition to training and competition, may predispose the young basketball player to increased injury risk. Future research using larger sample sizes are required to further investigate the role of participation volume and type on injury occurrence in adolescent athletes

Osteochondritis Dissecans of the Glenoid in a Major League Baseball Prospect: A Case Report.

Science.gov (United States)

Grau, Luis Carlos; Jose, Jean; Sama, Andrew Joseph; Baraga, Michael Gerald

2016-01-01

A 16-year-old Major League Baseball prospect presented with persistent shoulder pain associated with throwing. Magnetic resonance imaging (MRI) demonstrated a large osteochondritis dissecans lesion in the posterosuperior aspect of the glenoid. The patient was restricted from throwing and underwent therapy to improve range of motion and throwing mechanics. Eight months after initiating nonoperative treatment, an MRI arthrogram demonstrated a healed lesion. At follow-up 2 years after treatment, full relief of symptoms had persisted. Osteochondritis dissecans lesions of the glenoid are extremely rare, but have the potential to heal in overhead-throwing athletes. To our knowledge, this is the only case reported in the literature that demonstrates a healed osteochondritis dissecans lesion of the glenoid following nonoperative treatment.

N-player quantum games in an EPR setting.

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James M Chappell

Full Text Available The N-player quantum games are analyzed that use an Einstein-Podolsky-Rosen (EPR experiment, as the underlying physical setup. In this setup, a player's strategies are not unitary transformations as in alternate quantum game-theoretic frameworks, but a classical choice between two directions along which spin or polarization measurements are made. The players' strategies thus remain identical to their strategies in the mixed-strategy version of the classical game. In the EPR setting the quantum game reduces itself to the corresponding classical game when the shared quantum state reaches zero entanglement. We find the relations for the probability distribution for N-qubit GHZ and W-type states, subject to general measurement directions, from which the expressions for the players' payoffs and mixed Nash equilibrium are determined. Players' N x N payoff matrices are then defined using linear functions so that common two-player games can be easily extended to the N-player case and permit analytic expressions for the Nash equilibrium. As a specific example, we solve the Prisoners' Dilemma game for general N ≥ 2. We find a new property for the game that for an even number of players the payoffs at the Nash equilibrium are equal, whereas for an odd number of players the cooperating players receive higher payoffs. By dispensing with the standard unitary transformations on state vectors in Hilbert space and using instead rotors and multivectors, based on Clifford's geometric algebra (GA, it is shown how the N-player case becomes tractable. The new mathematical approach presented here has wide implications in the areas of quantum information and quantum complexity, as it opens up a powerful way to tractably analyze N-partite qubit interactions.

Player Modeling for Intelligent Difficulty Adjustment

Science.gov (United States)

Missura, Olana; Gärtner, Thomas

In this paper we aim at automatically adjusting the difficulty of computer games by clustering players into different types and supervised prediction of the type from short traces of gameplay. An important ingredient of video games is to challenge players by providing them with tasks of appropriate and increasing difficulty. How this difficulty should be chosen and increase over time strongly depends on the ability, experience, perception and learning curve of each individual player. It is a subjective parameter that is very difficult to set. Wrong choices can easily lead to players stopping to play the game as they get bored (if underburdened) or frustrated (if overburdened). An ideal game should be able to adjust its difficulty dynamically governed by the player’s performance. Modern video games utilise a game-testing process to investigate among other factors the perceived difficulty for a multitude of players. In this paper, we investigate how machine learning techniques can be used for automatic difficulty adjustment. Our experiments confirm the potential of machine learning in this application.

Secure Multi-Player Protocols

DEFF Research Database (Denmark)

Fehr, Serge

While classically cryptography is concerned with the problem of private communication among two entities, say players, in modern cryptography multi-player protocols play an important role. And among these, it is probably fair to say that secret sharing, and its stronger version verifiable secret...... sharing (VSS), as well as multi-party computation (MPC) belong to the most appealing and/or useful ones. The former two are basic tools to achieve better robustness of cryptographic schemes against malfunction or misuse by “decentralizing” the security from one single to a whole group of individuals...... (captured by the term threshold cryptography). The latter allows—at least in principle—to execute any collaboration among a group of players in a secure way that guarantees the correctness of the outcome but simultaneously respects the privacy of the participants. In this work, we study three aspects...

Physical demands on young elite European female basketball players with special reference to speed, agility, explosive strength, and take-off power.

Science.gov (United States)

Erčulj, Frane; Blas, Mateja; Bračič, Mitja

2010-11-01

The aim of the study was to determine and analyze the level of certain motor abilities (acceleration and agility, the explosive strength of arms, and take-off power) of young elite European female basketball players. We also wanted to establish whether there were any differences between 3 groups of female basketball players who differed in terms of their playing performance. The sample of subjects consists of 65 female basketball players aged 14.49 (± 0.61) years who were divided into 3 groups (divisions A, B, and C of the European Championships). We compare the groups by using 8 motor tests. p Values training status, this is also 1 of the key reasons for these players' lower playing efficiency compared to those from divisions A and B. We hope the findings of this study will enable the generation of model values, which can assist basketball coaches for this age category in basketball clubs, high schools, national teams, and basketball camps.

Concussion Characteristics in High School Football by Helmet Age/Recondition Status, Manufacturer, and Model: 2008-2009 Through 2012-2013 Academic Years in the United States.

Science.gov (United States)

Collins, Christy L; McKenzie, Lara B; Ferketich, Amy K; Andridge, Rebecca; Xiang, Huiyun; Comstock, R Dawn

2016-06-01

Football helmets used by high school athletes in the United States should meet the National Operating Committee on Standards for Athletic Equipment performance standards. Despite differences in interior padding and exterior shells, all football helmets should provide comparable protection against concussions. Yet, debate continues on whether differences in the rates or severity of concussions exist based on helmet age/recondition status, manufacturer, or model. To investigate whether high school football concussion characteristics varied by helmet age/recondition status, manufacturer, and model. Descriptive epidemiological study. High school football concussion and helmet data were collected from academic years 2008-2009 through 2012-2013 as part of the National High School Sports-Related Injury Surveillance Study. The certified athletic trainers of participating schools submitted athlete-exposure (AE) and injury information weekly. Participating schools reported 2900 football concussions during 3,528,790 AEs for an overall rate of 8.2 concussions per 10,000 AEs. Concussion rates significantly increased from 2008-2009 through 2012-2013 overall (P = .006) as well as in competition (P = .027) and practice (P = .023). Characteristics of concussed football players (ie, mean number of symptoms, specific concussion symptoms, symptom resolution time, and time until return to play) were similar among players wearing new helmets when compared with reconditioned helmets. Fewer players wearing an old/not reconditioned helmet had concussion symptoms resolve within 1 day compared with players wearing a new helmet. Despite differences in the manufacturers and models of helmets worn by all high school football players compared with players who sustained a concussion, the mean number of concussion symptoms, specific concussion symptoms, symptom resolution time, and time until return to play were similar for concussions sustained by football players wearing the most common helmet

Relative age effect and its relationship with morphological characteristics and performance in young soccer players

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Augusto Pedretti

2015-05-01

Full Text Available DOI: http://dx.doi.org/10.5007/1980-0037.2015v17n3p367   In soccer, the relative age effect (RAE was observed in both adult and young players. The RAE appears to be more pronounced in elite sports, probably by the need to select the best players to compete internationally. This study review: (1 the prevalence of RAE in soccer players, (a considering competitive level (b and specific position and (2 association between RAE (a and anthropometric characteristics, (b physical fitness components and technical skills. A total of 12 studies met all inclusion criteria for this review. One trial (meta-analysis was included after the eligibility process. Overall, 77675 young soccer players were analysed. In all studies, significance level of 0.05 was set for the type I error. There is a consensus about the presence of an RAE in men’s soccer, and the percentage of players born in the first quarter in the selection year for professionals is high, with peak values found for elite young athletes, and a large decrease is evident throughout the regional and school representation. The relationship between RAE and the specific position is controversial, according to few studies. It is likely that players born in the first quarter differ in a variety of anthropometric characteristics and physical fitness components compared with peers born in the last quarter. Researchers need to understand the mechanisms by which RAE increase and decrease in order, to reduce and eliminate this social inequality that influence the experiences of athletes, especially in periods of development. Organizational and practical intervention is required.

Methods for detrending success metrics to account for inflationary and deflationary factors*

Science.gov (United States)

Petersen, A. M.; Penner, O.; Stanley, H. E.

2011-01-01

Time-dependent economic, technological, and social factors can artificially inflate or deflate quantitative measures for career success. Here we develop and test a statistical method for normalizing career success metrics across time dependent factors. In particular, this method addresses the long standing question: how do we compare the career achievements of professional athletes from different historical eras? Developing an objective approach will be of particular importance over the next decade as major league baseball (MLB) players from the "steroids era" become eligible for Hall of Fame induction. Some experts are calling for asterisks (*) to be placed next to the career statistics of athletes found guilty of using performance enhancing drugs (PED). Here we address this issue, as well as the general problem of comparing statistics from distinct eras, by detrending the seasonal statistics of professional baseball players. We detrend player statistics by normalizing achievements to seasonal averages, which accounts for changes in relative player ability resulting from a range of factors. Our methods are general, and can be extended to various arenas of competition where time-dependent factors play a key role. For five statistical categories, we compare the probability density function (pdf) of detrended career statistics to the pdf of raw career statistics calculated for all player careers in the 90-year period 1920-2009. We find that the functional form of these pdfs is stationary under detrending. This stationarity implies that the statistical regularity observed in the right-skewed distributions for longevity and success in professional sports arises from both the wide range of intrinsic talent among athletes and the underlying nature of competition. We fit the pdfs for career success by the Gamma distribution in order to calculate objective benchmarks based on extreme statistics which can be used for the identification of extraordinary careers.

Comparison of Shoulder Strength in Routinely Trained Badminton Players and Non-Badminton Players

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Wong Zhen Feng

2017-06-01

Full Text Available Background: Shoulder pain is a common reason for patients to seek medical help in any healthcare center. Shoulder pain is influenced by a few factors such as gender, posture during daily activities, aging and psychological factors. Based on the study of Epidemiology of Injuries and Prevention Strategies in Competitive Swimmers, shoulder pain due to shoulder injuries can be reduced by strengthening the shoulder muscle. Badminton has become one of the most popular sports in Asia, especially in Indonesia. This study was conducted to determine if badmintonis able to strengthen the shoulder muscle group. Methods: A cross-sectional analytic experimental study was conducted on September 2015 at Lodaya Badminton Training Center and Bale Padjadjaran of Universitas Padjadjaran. Subjects were 30 healthy male routinely trained badminton players and 30 non-badminton players who voluntarily follow the rstudy procedures. Strength measurement procedures were provided to the subjects after getting informed consent.  Data analysis was performed using T-test. Results: The shoulder strength  in routinely trained badminton players was significantly different from  non-badminton players (P<0.05. Conclusions: Shoulder strength can be improved through routine training of badminton to reduce risk of shoulder injury.   DOI: 10.15850/amj.v4n2.1083

The epidemiology of 1345 shoulder dislocations and subluxations in French Rugby Union players: a five-season prospective study from 2008 to 2013.

Science.gov (United States)

Bohu, Yoann; Klouche, Shahnaz; Lefevre, Nicolas; Peyrin, Jean-Claude; Dusfour, Bernard; Hager, Jean-Philippe; Ribaut, Aurélie; Herman, Serge

2015-12-01

An understanding of the epidemiology of shoulder dislocation/subluxation in rugby union players could help develop targeted prevention programmes and treatment. We performed a multiyear epidemiological survey of shoulder dislocation/subluxation in a large cohort of rugby players. A descriptive epidemiological study was performed prospectively for five playing seasons (2008-2013) in all players licensed in the French Rugby Union. Rugby players were categorised into five groups by age. The player and the team physician reported the injury to the club insurance company if it occurred during training or a match. The goals of the study were to define the rate, type and causes of shoulder dislocation/subluxation. 88,044 injuries were reported, including 1345 (1.5%) episodes of dislocation/subluxation in 1317 men and 28 women, mean age 22.5±5.9 years. About 10/10,000 men and 5/10,000 women reported an episode of shoulder dislocation/subluxation per season, including 83/10,000 senior professionals, 17/10,000 senior amateurs, 21/10,000 juniors, 12/10,000 cadets and rugby school players. Shoulder dislocation/subluxation was significantly more frequent in senior and junior players (prugby players with a history of shoulder dislocation/subluxation should receive special attention from sports medicine professionals and orthopaedic surgeons. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Injury incidence and characteristics in South African school first team ...

African Journals Online (AJOL)

Kathryn van Boom

2016-01-01

Jan 1, 2016 ... of games played within the season, and the overlap of school and provincial ..... Preventing injuries in children playing school rugby (cited 11. March. 2016). ... under-18 players: real-match video analysis. Br J Sports Med.

Accuracy of professional sports drafts in predicting career potential.

Science.gov (United States)

Koz, D; Fraser-Thomas, J; Baker, J

2012-08-01

The forecasting of talented players is a crucial aspect of building a successful sports franchise and professional sports invest significant resources in making player choices in sport drafts. The current study examined the relationship between career performance (i.e. games played) and draft round for the National Football League, National Hockey League, National Basketball League, and Major League Baseball for players drafted from 1980 to 1989 (n = 4874) against the assumption of a linear relationship between performance and draft round (i.e. that players with the most potential will be selected before players of lower potential). A two-step analysis revealed significant differences in games played across draft rounds (step 1) and a significant negative relationship between draft round and games played (step 2); however, the amount of variance accounted for was relatively low (less than 17%). Results highlight the challenges of accurately evaluating amateur talent. © 2011 John Wiley & Sons A/S.

Does expert perceptual anticipation transfer to a dissimilar domain?

Science.gov (United States)

Müller, Sean; McLaren, Michelle; Appleby, Brendyn; Rosalie, Simon M

2015-06-01

The purpose of this experiment was to extend theoretical understanding of transfer of learning by investigating whether expert perceptual anticipation skill transfers to a dissimilar domain. The capability of expert and near-expert rugby players as well as novices to anticipate skill type within rugby (learning sport) was first examined using a temporal occlusion paradigm. Participants watched video footage of an opponent performing rugby skill types that were temporally occluded at different points in the opponent's action and then made a written prediction. Thereafter, the capability of participants to transfer their anticipation skill to predict pitch type in baseball (transfer sport) was examined. Participants watched video footage of a pitcher throwing different pitch types that were temporally occluded and made a written prediction. Results indicated that expert and near-expert rugby players anticipated significantly better than novices across all occlusion conditions. However, none of the skill groups were able to transfer anticipation skill to predict pitch type in baseball. The findings of this paper, along with existing literature, support the theoretical prediction that transfer of perceptual anticipation is expertise dependent and restricted to similar domains. (c) 2015 APA, all rights reserved).

How Players Lose Interest in Playing a Game

DEFF Research Database (Denmark)

Bauckhage, Christian; Kersting, Kristian; Sifa, Rafet

2012-01-01

introduce methods from random process theory into game data mining in order to draw inferences about player engagement. Given large samples (over 250,000 players) of behavioral telemetry data from five different action-adventure and shooter games, we extract information as to how long individual players......Analyzing telemetry data of player behavior in computer games is a topic of increasing interest for industry and research, alike. When applied to game telemetry data, pattern recognition and statistical analysis provide valuable business intelligence tools for game development. An important problem...... in this area is to characterize how player engagement in a game evolves over time. Reliable models are of pivotal interest since they allow for assessing the long-term success of game products and can provide estimates of how long players may be expected to keep actively playing a game. In this paper, we...

Effect of coach change on professional tennis players

OpenAIRE

Nekolová, Barbora

2014-01-01

Title: Effect of coach change on professional tennis players Objectives of work: The aim of the thesis is to analyze the impact of coach change on professional tennis players from the psychology perspective, social relationship and player's attitude to the sport itself. The impact of the coach change on player's approach to tennis, game results, personal life and interpersonal relationships will be examined. Method: The methods that will be used are narrative interviews - annotated transcript...

Profile of Physical Fitness of Young Football Players at SDN Cibeusi

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Subashini Periasamy

2015-06-01

Full Text Available Background: Health-related physical fitness components are important in hypokinetic disease prevention and good sports performance. The aim of this research is to evaluate the physical fitness profile of the SDN Cibeusi young football players based on Fitnessgram. Methods: This study was participated by 20 subjects ranging from 10 to 12 years old boys who played for the school football team in SDN Cibeusi. This descriptive study was conducted in the school field in the month of November 2012. Physical fitness components that were tested are aerobic capacity,V02 max using the one-mile run test, muscle endurance by performing push-up and curl-up test, flexibility using the flexometer and body composition by measuring the body mass index and fat fold measurement. The mean and standard deviation of the results were tabulated. Results: Aerobic capacity and percentage of body fat showed 100% of them scored in the category of healthy fitness zone. For body mass index, 55% scored in healthy fitness zone, 25% ni-some risk, and 10% each for ni-high risk and very lean. For push-up test and curl-up test, 80% and 65% scored in the healthy fitness zone while the remaining 20% and 35% respectively scored in the not healthy fitness zone. For flexibility, 75% of them scored in healthy fitness zone and 25% scored in not healthy fitness zone. Conclusions: The physical fitness level in these young football players is mostly in healthy fitness zone.

Brooklyn et "ses" Dodgers. Base-ball et construction des identités urbaines aux Etats-Unis, une sociohistoire (1883-1957)

OpenAIRE

Marquis , Peter

2009-01-01

From the 1880s onwards, baseball has played a considerable role in the shaping of urban cultures in the United States. The Dodgers, a professional team based in the New York borough of Brooklyn, provide a remarkable illustration of the rarely studied interaction between urban identities, people's passion for sports, and the history of entertainment businesses. From their birth in 1883 to their much-contested move to Los Angeles in 1957, the Dodgers have established themselves as Brooklyn's ho...

Bridging Media with the Help of Players

Science.gov (United States)

Nitsche, Michael; Drake, Matthew; Murray, Janet

We suggest harvesting the power of multiplayer design to bridge content across different media platforms and develop player-driven cross-media experiences. This paper first argues to partially replace complex AI systems with multiplayer design strategies to provide the necessary level of flexibility in the content generation for cross-media applications. The second part describes one example project - the Next Generation Play (NGP) project - that illustrates one practical approach of such a player-driven cross-media content generation. NGP allows players to collect virtual items while watching a TV show. These items are re-used in a multiplayer casual game that automatically generates new game worlds based on the various collections of active players joining a game session. While the TV experience is designed for the single big screen, the game executes on multiple mobile phones. Design and technical implementation of the prototype are explained in more detail to clarify how players carry elements of television narratives into a non-linear handheld gaming experience. The system describes a practical way to create casual game adaptations based on players' personal preferences in a multi-user environment.

Vitamin D profile in National Football League players.

Science.gov (United States)

Maroon, Joseph C; Mathyssek, Christina M; Bost, Jeffrey W; Amos, Austin; Winkelman, Robert; Yates, Anthony P; Duca, Mark A; Norwig, John A

2015-05-01

By maintaining phosphate and calcium homeostasis, vitamin D is critical for bone health and possibly physical performance. Hence, vitamin D is important to athletes. Few studies have investigated vitamin D levels in relation to fractures and performance in athletes, and no published study has included a multiracial sample of professional American football players. To assess vitamin D levels, including the prevalence of vitamin D deficiency/insufficiency, in professional American football players and to evaluate the association of vitamin D levels with race, fracture history, and the ability to obtain a contract position, which may be a marker for athletic performance. Cohort study; Level of evidence, 3. Serum vitamin D levels of 80 professional football players from a single team in the National Football League were obtained during the 2011 off-season (mean age, 26.5±3.7 years; black, n=67 [84%]). These levels were used to compare injury reports from the 2011-2012 and 2012-2013 seasons. Statistical analyses were performed to test if vitamin D levels were related to race, fracture history, and the ability to obtain a contract position. Mean vitamin D level was 27.4±11.7 ng/mL, with significantly lower levels for black players (25.6±11.3 ng/mL) versus white players (37.4±8.6 ng/mL; F 1,78=13.00, P=.001). All athletes who were vitamin D deficient were black. When controlling for number of professional years played, vitamin D levels were significantly lower in players with at least 1 bone fracture when compared with no fractures. Players who were released during the preseason because of either injury or poor performance had significantly lower vitamin D levels than did players who played in the regular season. Black professional football players have a higher rate of vitamin D deficiency than do white players. Furthermore, professional football players with higher vitamin D levels were more likely to obtain a contract position in the National Football League

Outcomes of microfracture in professional basketball players.

Science.gov (United States)

Cerynik, Douglas L; Lewullis, Gabriel E; Joves, Brian C; Palmer, Michael P; Tom, James A

2009-09-01

Surgical treatment for chondral defects of the knee in competitive running and jumping athletes remains controversial. This study evaluated the performance outcomes of professional basketball players in the National Basketball Association (NBA) who underwent microfracture. Data from 24 professional basketball players from 1997 to 2006 was obtained and analyzed. NBA player efficiency ratings (PER) were calculated for two seasons before and after injury. A control group of 24 players was used for comparison. Study group and control group demographics including age, NBA experience, and minutes per game demonstrated no statistical difference. Mean time to return to an NBA game was 30.0 weeks from the time of surgery. The first season after returning to competition PER and minutes per game decreased by 3.5 (P 0.05) and 3.0 min (P NBA game. On return to competition player performance and minutes per game are diminished.

Injuries in Spanish female soccer players

Directory of Open Access Journals (Sweden)

Juan Del Coso

2018-04-01

Full Text Available Background: Epidemiologic research to learn the incidence, type, location, and severity of female soccer injuries and the risk factors for sustaining a sport injury is the first step in developing preventive policies. The aim of this study was to analyze the incidence of injuries in the population of female soccer players in Spain. Methods: The injuries incurred by 25,397 female soccer players were registered by the medical staff of the Spanish Football Federation during 1 season. A standardized medical questionnaire was used to classify the injury according to type, severity, location, and injury mechanism. A total of 2108 injuries was reported with an incidence of 0.083 injuries per player per season. Most injuries were in the lower limbs (74.0%, mainly affecting knee (30.4% and ankle joints (17.9%. Results: The proportion of injuries derived from contact with another player was higher during matches (33.7% than during training (11.4%; p  0.05. Conclusion: Most female soccer injuries were located at the knee and ankle; the injury mechanism determined the playing time lost; and the player's age did not affect injury characteristics. Keywords: Ankle, Epidemiology, Knee, Sport injuries, Women

A comparison of U18 school and academy rugby union match play

OpenAIRE

Read, D; Jones, B; Till, K

2016-01-01

Introduction Understanding the physical demands of rugby union can assist coaches in the preparation of players. Match demands in senior players for domestic competitions (Cahill et al., 2013) and international games (Quarrie et al., 2013) are well established. However, despite adolescent rugby union players playing concurrently at various standards, there is no study that has attempted to compare them. Therefore, the purpose of this study was to compare the physical demands of U18 school vs....

Towards Player-Driven Procedural Content Generation

DEFF Research Database (Denmark)

Shaker, Noor; Yannakakis, Georgios N.; Togelius, Julian

2012-01-01

Generating immersive game content is one of the ultimate goals for a game designer. This goal can be achieved by realizing the fact that players’ perception of the same game differ according to a number of factors including: players’ personality, playing styles, expertise and culture background....... While one player might find the game immersive, others may quit playing as a result of encountering a seemingly insoluble problem. One promising avenue towards optimizing the gameplay experience for individual game players is to tailor player experience in real-time via automatic game content generation......-driven content generation....

Sex-specific differences in injury types among basketball players.

Science.gov (United States)

Ito, Eri; Iwamoto, Jun; Azuma, Koichiro; Matsumoto, Hideo

2015-01-01

The purpose of the present study was to investigate sex-specific differences in injury types among basketball players. According to our database, during the 20-year period between October 1991 and June 2011, 1,219 basketball players (640 males and 579 females) consulted our sports medicine clinic; in total, 1,414 injuries in basketball players (729 injuries in males and 685 injuries in females) were recorded. The mean age of patients was 19.6 years. The most common injury site was the knee, followed by the foot and ankle, lower back, and upper extremities. There was a higher proportion of female players presenting with a knee injury, compared with male players (50.4% vs 41.7%), and a lower proportion of female players presenting with an upper extremity injury (5.1% vs 9.7%). The proportion of anterior cruciate ligament injury in the 10-19-year-old age group was higher among female players than among male players (45.9% vs 22.1%), while the proportions of Osgood-Schlatter disease in the 10-19-year-old age group and jumper's knee (patellar and femoral tendinopathy) in the 20-29-year-old age group were higher among male players than among female players (12.5% vs 1.8% and 14.6% vs 3.7%, respectively). However, the proportions of other injuries did not differ significantly between male and female players. The present observational study, which was performed using a retrospective case-series design, showed the existence of sex-specific differences in knee injuries sustained while participating in basketball.

The structure of physical fitness and its correlation analysis at young players aged 16-17 years at the stage of basic training

Directory of Open Access Journals (Sweden)

A.N. POPOV

2014-12-01

Full Text Available Purpose : The questions about the importance of physical fitness of young players to improve the management and correction of the training process. Material : In the research participated 40 players aged 16-17 years of specialized youth football school of FC "Obolon-Brewery". Data for the study of physical fitness were teacher observations and teacher testing carried out under the direct training of young players. Results : It is shown that the structure of physical fitness among all the studied parameters there is a close correlation relationship, except for a parameter that characterizes the start speed. It was found that the above regularities indicate the advisability of excluding the studied parameters in the structure of physical fitness of young players to improve the efficiency of the training process at the base of specialized training. Conclusions : It is recommended to improve the starting speed to use non-gaming and technical and tactical exercises.

The El Dorado of Handball? Foreign Female Players Stay, while Domestic Players Return from Abroad

Science.gov (United States)

Topič, Mojca Doupona; Šibila, Marko

2016-01-01

Abstract The main purpose of this research was to study the characteristics of migration in European women’s handball based on the Slovenian example and to find the differences between the foreigners coming to Slovenia and the Slovenians transferring to foreign clubs. The research was based on 16 open face-to-face semi-structured interviews (8 Slovenians (age 29.5 ± 6.2 years) and 8 foreigners (age 35.5 ± 8.7 years)). We found out that the most powerful factor in foreigners was the financial one, while within Slovenian players it was their personal desire for progression within their sport, the club’s reputation and poor conditions in their previous club. The results confirm that when making a decision on transfer, all players had the support of family and friends, while the clubs of foreign players were not as supportive. Most interviewees considered their careers successful and did not regret going abroad. The research indicates that the largest differences discovered between Slovenians and foreigners were that foreign female players chose to stay in the new country (Slovenia), while domestic players returned home after few years playing abroad. In conclusion, the results show that in top-level handball there are important differences between migration models which are based on nationality and also that the migration models change throughout time, which is largely connected with the socioeconomic events in the country of origin or transfer. PMID:28149349

The El Dorado of Handball? Foreign Female Players Stay, while Domestic Players Return from Abroad

Directory of Open Access Journals (Sweden)

Bon Marta

2016-04-01

Full Text Available The main purpose of this research was to study the characteristics of migration in European women’s handball based on the Slovenian example and to find the differences between the foreigners coming to Slovenia and the Slovenians transferring to foreign clubs. The research was based on 16 open face-to-face semi-structured interviews (8 Slovenians (age 29.5 ± 6.2 years and 8 foreigners (age 35.5 ± 8.7 years. We found out that the most powerful factor in foreigners was the financial one, while within Slovenian players it was their personal desire for progression within their sport, the club’s reputation and poor conditions in their previous club. The results confirm that when making a decision on transfer, all players had the support of family and friends, while the clubs of foreign players were not as supportive. Most interviewees considered their careers successful and did not regret going abroad. The research indicates that the largest differences discovered between Slovenians and foreigners were that foreign female players chose to stay in the new country (Slovenia, while domestic players returned home after few years playing abroad. In conclusion, the results show that in top-level handball there are important differences between migration models which are based on nationality and also that the migration models change throughout time, which is largely connected with the socioeconomic events in the country of origin or transfer.

The shoulder in baseball pitching: biomechanics and related injuries-part 1.

Science.gov (United States)

Park, Samuel S; Loebenberg, Mark L; Rokito, Andrew S; Zuckerman, Joseph D

The extreme range of motion at the shoulder, the high angular velocities and torques, and the repetitious nature of the pitching motion combine to make the shoulder vulnerable to injury during the baseball pitch. An understanding of the biomechanics that contribute to shoulder injuries during each phase of the pitching motion can facilitate the athlete's diagnosis, treatment, and rehabilitation. Common injuries that occur during the late cocking and acceleration phases of the pitch include anterior instability and impingement, bicipital tendinitis, and subacromial impingement. Nonoperative treatment consisting of an initial period of rest and NSAIDS, followed by physical therapy and a gradual return to activity, is usually successful. When this approach fails, surgical intervention, either arthroscopic or open, may be necessary. Physical therapy and rehabilitation are directed toward restoring the integrity and strength of the dynamic and static stabilizers of the shoulder joint, yet preserving the range of motion necessary for performance. Through rehabilitation, the dedicated athlete can often return to the pitching mound at his previous level of performance.

Efficiently detecting outlying behavior in video-game players.

Science.gov (United States)

Kim, Young Bin; Kang, Shin Jin; Lee, Sang Hyeok; Jung, Jang Young; Kam, Hyeong Ryeol; Lee, Jung; Kim, Young Sun; Lee, Joonsoo; Kim, Chang Hun

2015-01-01

In this paper, we propose a method for automatically detecting the times during which game players exhibit specific behavior, such as when players commonly show excitement, concentration, immersion, and surprise. The proposed method detects such outlying behavior based on the game players' characteristics. These characteristics are captured non-invasively in a general game environment. In this paper, cameras were used to analyze observed data such as facial expressions and player movements. Moreover, multimodal data from the game players (i.e., data regarding adjustments to the volume and the use of the keyboard and mouse) was used to analyze high-dimensional game-player data. A support vector machine was used to efficiently detect outlying behaviors. We verified the effectiveness of the proposed method using games from several genres. The recall rate of the outlying behavior pre-identified by industry experts was approximately 70%. The proposed method can also be used for feedback analysis of various interactive content provided in PC environments.

Head Impact Exposure in Junior and Adult Australian Football Players

Directory of Open Access Journals (Sweden)

Mark Hecimovich

2018-01-01

Full Text Available This study measured and compared the frequency, magnitude, and distribution of head impacts sustained by junior and adult Australian football players, respectively, and between player positions over a season of games. Twelve junior and twelve adult players were tracked using a skin-mounted impact sensor. Head impact exposure, including frequency, magnitude, and location of impacts, was quantified using previously established methods. Over the collection period, there were no significant differences in the impact frequency between junior and adult players. However, there was a significant increase in the frequency of head impacts for midfielders in both grades once we accounted for player position. A comparable amount of head impacts in both junior and adult players has implications for Australian football regarding player safety and medical coverage as younger players sustained similar impact levels as adult players. The other implication of a higher impact profile within midfielders is that, by targeting education and prevention strategies, a decrease in the incidence of sports-related concussion may result.

The patellar tendon in junior elite volleyball players and an Olympic elite weightlifter

OpenAIRE

Gisslén, Karl

2006-01-01

The principal aim of the present thesis was to prospectively follow (clinical status and ultrasound + Doppler findings) the patellar tendons in the young elite volleyball players at the Swedish National Centre for high school volleyball in Falköping. In an Olympic weightlifter with chronic painful jumper´s knee, the effects of treatment with sclerosing injections followed by early instituted very heavy weightlifting training, was also evaluated. First, in a prevalence study, we demonstrated t...

Morphological evolution of Springbok rugby players: Implications for ...

African Journals Online (AJOL)

The physique of rugby players has evolved over the course of the Twentieth Century. A novel morphological dataset was constructed of all Springbok rugby players until 2014. Although most of the change in body structure, particularly body weight, occurs during the era of professionalism, white Springbok rugby players ...

School governing bodies - the principal's burden or the light of his ...

African Journals Online (AJOL)

In this article I focus on the relationship between principals and school governing bodies in South Africa. Although the school governing body represents many role players, this article will focus mainly on the role and function of parent representatives in the school governing body. Parents constitute the majority in the ...

Football players, asset management & the unexploited potential of enhanced player engagement in football management & marketing

DEFF Research Database (Denmark)

Cortsen, Kenneth

2016-01-01

This article gives insights into why and how football brands (e.g. clubs and governing bodies) can benefit from enhancing the activation of players in football management and football marketing initiatives.......This article gives insights into why and how football brands (e.g. clubs and governing bodies) can benefit from enhancing the activation of players in football management and football marketing initiatives....

Football players, asset management & the unexploited potential of enhanced player engagement in football management & marketing

DEFF Research Database (Denmark)

Cortsen, Kenneth

2014-01-01

This article gives insights into why and how football brands (e.g. clubs and governing bodies) can benefit from enhancing the activation of players in football management and football marketing initiatives.......This article gives insights into why and how football brands (e.g. clubs and governing bodies) can benefit from enhancing the activation of players in football management and football marketing initiatives....

Swimming literacy field hockey woman player ground.

OpenAIRE

Baštová, Miroslava

2012-01-01

Title: Swimming literacy field hockey woman player ground. Objectives: To obtain and analyze data on the level ground swimming literacy field hockey woman player. Their perception swimming literacy for life, the use of non-specific regeneration and as a training resource. Methods: Analysis of scientific literature, survey, case study, data analysis and graphical presentation of results. Results of the work: field hockey player as swimming literate, benefits swimming but not used as a means of...

Protective equipment use among female rugby players.

Science.gov (United States)

Comstock, R Dawn; Fields, Sarah K; Knox, Christy L

2005-07-01

Our objective was to assess the prevalence of protective equipment use and the motivation for using protective equipment among a sample of US female rugby players. We surveyed a convenience sample of 234 current US female rugby players from 14 teams participating in a US women's rugby tournament, obtaining self-reported demographic, rugby exposure, and protective equipment use information. Mouthguards were the most commonly used piece of protective equipment: 90.8% of players reported having always worn a mouthguard while playing or practicing rugby within their most recent 3 months of play. Fewer than 15% of players reported having always worn other types of protective equipment. Equipment use varied by playing position. Whereas over 80% of players in all other positions always wore a mouthguard, 66.7% of scrum halves reported always wearing one. Both backs and forwards reported wearing shoulder pads, but only forwards reported always wearing padded headgear. Mouthguards, padded headgear, and shoulder pads were worn "to prevent injury," whereas ankle braces, neoprene sleeves, and athletic tape on joints were worn "to protect a current/recent injury." This is the first study of female rugby players to assess the prevalence of protective equipment use by playing position and the motivation for using protective equipment. With the exception of mouthguards, US female rugby players infrequently use protective equipment. Protective equipment use varies by playing position. Some types of protective equipment appear to be used as primary prevention mechanisms, whereas others are used as secondary or tertiary prevention mechanisms.

The Relationship of Throwing Arm Mechanics and Elbow Varus Torque: Within-Subject Variation for Professional Baseball Pitchers Across 82,000 Throws.

Science.gov (United States)

Camp, Christopher L; Tubbs, Travis G; Fleisig, Glenn S; Dines, Joshua S; Dines, David M; Altchek, David W; Dowling, Brittany

2017-11-01

Likely due to the high level of strain exerted across the elbow during the throwing motion, elbow injuries are on the rise in baseball. To identify at-risk athletes and guide postinjury return-to-throw programs, a better understanding of the variables that influence elbow varus torque is desired. To describe the within-subject relationship between elbow varus torque and arm slot and arm rotation in professional baseball pitchers. Descriptive laboratory study. A total of 81 professional pitchers performed 82,000 throws while wearing a motusBASEBALL sensor and sleeve. These throws represented a combination of throw types, such as warm-up/catch, structured long-toss, bullpen throwing from a mound, and live game activity. Variables recorded for each throw included arm slot (angle of the forearm relative to the ground at ball release), arm speed (maximal rotational velocity of the forearm), arm rotation (maximal external rotation of the throwing arm relative to the ground), and elbow varus torque. Linear mixed-effects models and likelihood ratio tests were used to estimate the relationship between elbow varus torque and arm slot, arm speed, and arm rotation within individual pitchers. All 3 metrics-arm slot (χ 2 = 428, P relationship with elbow varus torque. Within individual athletes, a 1-N.m increase in elbow varus torque was associated with a 13° decrease in arm slot, a 116 deg/s increase in arm speed, and an 8° increase in arm rotation. Elbow varus torque increased significantly as pitchers increased their arm rotation during the arm cocking phase, increased the rotational velocity of their arm during the arm acceleration phase of throwing, and decreased arm slot at ball release. Thus, shoulder flexibility, arm speed, and elbow varus torque (and likely injury risk) are interrelated and should be considered collectively when treating pitchers. It is well established that elbow varus torque is related to ulnar collateral ligament injuries in overhead throwers. This

Correlation among Y Balance Test-Lower Quarter Composite Scores, Hip Musculoskeletal Characteristics, and Pitching Kinematics in NCAA Division I Baseball Pitchers.

Science.gov (United States)

Culiver, Adam; Garrison, J Craig; Creed, Kalyssa M; Conway, John E; Goto, Shiho; Werner, Sherry

2018-01-24

Numerous studies have reported kinematic data on baseball pitchers using 3D motion analysis, but no studies to date have correlated this data with clinical outcome measures. To examine the relationship among Y Balance Test-Lower Quarter (YBT-LQ) composite scores, musculoskeletal characteristics of the hip and pitching kinematics in NCAA Division I baseball pitchers. Cross-sectional. 3D motion analysis laboratory. 19 healthy male collegiate baseball pitchers. Internal and external hip passive range of motion (PROM); hip abduction strength; YBT-LQ composite scores; kinematic variables of the pitching motion. Stride length demonstrated a moderate positive correlation with dominant limb YBT-LQ composite score (r=0.524, p=0.018) and non-dominant limb YBT-LQ composite score (r=0.550, p=0.012), and a weak positive correlation with normalized time to maximal humerus velocity (r=0.458, p=0.043). Stride length had a moderate negative correlation with normalized time to maximal thorax velocity (r= -0.522, p=0.018) and dominant hip TRM (r= -0.660, p=0.002), and had a strong negative correlation with normalized time from SFC to maximal knee flexion (r= -0.722, pcorrelation with hip abduction strength difference (r= -0.459, p=0.042) and normalized time to maximal thorax velocity (r= -0.468, p=0.037), as well as a moderate negative correlation with dominant hip TRM (r= -0.160, p=0.004). Non-dominant limb YBT-LQ composite score demonstrated a weak negative correlation with normalized time to maximal thorax velocity (r= -0.450, p=0.046) and had a moderate negative correlation with dominant hip TRM (r= -0.668, p=0.001). Hip abduction strength difference demonstrated a weak positive correlation with dominant hip TRM (r=0.482, p=0.032). Dominant hip TRM had a moderate positive correlation with normalized time to maximal thorax velocity (r=0.484, p=0.031). There were no other significant relationships between the remaining variables. YBT-LQ is a clinical measure which can be used to

Strength asymmetry of the shoulders in elite volleyball players.

Science.gov (United States)

Hadzic, Vedran; Sattler, Tine; Veselko, Matjaž; Markovic, Goran; Dervisevic, Edvin

2014-01-01

Volleyball players are reported to have shoulder strength imbalances. Previous authors have primarily investigated small samples of male players at a single skill level, without considering playing position, and with inconsistent findings. To evaluate shoulder strength asymmetry and a history of shoulder injury in a large sample of professional volleyball players of both sexes across different playing positions and skill levels. Descriptive laboratory study. A sample of 183 volleyball players (99 men, 84 women). We assessed shoulder internal-rotator and external-rotator concentric strength at 60°/s using an isokinetic dynamometer and dominant-nondominant differences in shoulder strength and strength ratios using repeated-measures analyses of variance. Peak torque was normalized for body mass and external-rotation/internal-rotation concentric strength. Internal-rotation strength was asymmetric in favor of the dominant side in both sexes, regardless of previous shoulder injury status. Male volleyball players had a lower shoulder strength ratio on the dominant side, regardless of previous shoulder injury status. However, this finding was valid only when hand dominance was taken into account. Female volleyball players playing at a higher level (ie, first versus second division) were 3.43 times more likely to have an abnormal strength ratio. Playing position was not associated with an abnormal shoulder strength ratio or strength asymmetry. In male volleyball players, the external-rotation/internal-rotation strength ratio of the dominant shoulder was lower, regardless of playing position, skill level, or a previous shoulder injury. In female players, the ratio was less only in those at a higher skill level. Although speculative, these findings generally suggest that female volleyball players could have a lower risk of developing shoulder-related problems than male volleyball players. Isokinetic shoulder testing may reveal important information about the possible risk

Education effect of solar car for technical high school student; Kogyo kokosei ni taisuru solar car no kyoiku koka

Energy Technology Data Exchange (ETDEWEB)

Inoue, T.

1998-09-30

The solar car race which technical high school students can join in was determined to be held at Ogata village, Akita prefecture. To join in the solar bicycle race, the author working in Ofuna technical high school called on 3 schools of Yokosuka, Fujisawa and Kanagawa technical high schools which joined in World Solar-Car Rally in Akita (WSR) in 1997, before fabrication of a racing bicycle. This paper describes the survey results at the above technical high schools, and the spirit as the teacher of Ofuna technical high school on joining in the race and fabrication of the solar bicycle, and the past, current and future situations. Club activities of high school students incline too toward sports such as soccer, baseball, volleyball and rugby, and are apt to keep honest cultural events and technical events at a distance. The author says that the challenge spirit to the solar car race using environment-friendly solar energy by both dedicated teachers and students of technical high schools summoned up the author`s courage. 15 figs.

Are squash players protecting their eyes?

Science.gov (United States)

Eime, R M; Finch, C F; Sherman, C A; Garnham, A P

2002-09-01

To determine factors associated with adult squash players' protective eyewear behaviours. A survey of 303 players (aged >or =18 years) was conducted at three squash venues in Melbourne, Australia over a three week period in June 2000 to obtain information about protective eyewear use. Of 303 participants the response rate was 98.1%; 66.1% were males, with a mean age of 40.5 years. The majority (68.4%) had played squash for 10 years or more. Although 18.8% of players reported using protective eyewear, only 8.9% reported wearing approved eyewear. Both age group (peye injuries (50.0%) and knowledge of eye injury risk (33.9%). A commonly reported barrier was restriction of vision (34.2%). These findings demonstrate a low prevalence of voluntary use of appropriate protective eyewear. Future prevention strategies incorporating education campaigns should focus on increasing players' knowledge of risks. The barriers to use and misconceptions about which types of eyewear is most protective need to be addressed as a priority.

MRI findings in little leaguer's shoulder

Energy Technology Data Exchange (ETDEWEB)

Song, James C.; Lazarus, Martin L. [Northwestern University and Evanston Northwestern Healthcare, Department of Radiology, Evanston, IL (United States); Song, Alexandra Pae [Health Department, Evanston, IL (United States)

2006-02-15

Little leaguer's shoulder, a stress injury of the proximal humeral physis, should be considered in the differential diagnosis for an adolescent baseball player with shoulder pain, especially if the player is pitching regularly in a competitive environment. While roentgenographs may or may not be helpful, depending on the duration and severity of the injury, we report the MRI appearance of a case of little leaguer's shoulder. We found MRI helpful in diagnosing injury to the growth plate that was radiographically occult; furthermore, we were able to document the patient's progress with a follow-up MRI examination, which showed improvement with treatment. (orig.)

Influences of Dynamic Level and Pitch Register on the Vibrato Rates and Widths of Violin and Viola Players

Science.gov (United States)

MacLeod, Rebecca B.

2008-01-01

The purpose of this study was to investigate possible influences of pitch register and dynamic level on vibrato rates and widths of university and high school violin and viola players. Analysis showed that pitch register significantly affected the vibrato rates and widths of the performers. Musicians vibrated 0.32 Hz faster and approximately 26…

Player behavioural modelling for video games

NARCIS (Netherlands)

van Lankveld, G.; Spronck, P.H.M.; Bakkes, S.C.J.

2012-01-01

Player behavioural modelling has grown from a means to improve the playing strength of computer programs that play classic games (e.g., chess), to a means for impacting the player experience and satisfaction in video games, as well as in cross-domain applications such as interactive storytelling. In

Self-determined motivation in rehabilitating professional rugby union players

OpenAIRE

Carson, F.; Polman, Remco C.J.

2017-01-01

Background The aim of the present study was to explore the views of professional rugby union players during the early rehabilitation, late rehabilitation and return to play stages, following anterior cruciate ligament (ACL) injury. Methods A qualitative dominant, mixed methodological approach was utilized with five players who had suffered an ACL injury requiring reconstructive surgery. A longitudinal approach, concurrent with each player?s rehabilitation, consisting of twice monthly intervie...

Physical Characteristics and Performance of Japanese Top-Level American Football Players.

Science.gov (United States)

Yamashita, Daichi; Asakura, Masaki; Ito, Yoshihiko; Yamada, Shinzo; Yamada, Yosuke

2017-09-01

Yamashita, D, Asakura, M, Ito, Y, Yamada, S, and Yamada, Y. Physical characteristics and performance of Japanese top-level American football players. J Strength Cond Res 31(9): 2455-2461, 2017-This study aimed to compare the physical characteristics and performance between top-level nonprofessional football players in Japan and National Football League (NFL) Combine invited players and between top-level and middle-level players in Japan to determine the factors that enhance performance in international and national competitions. A total of 168 American football players (>20 years) in Japan participated in an anthropometric (height and weight) and physical (vertical jump, long jump, 40-yard dash, pro-agility shuttle, 3-cone drill, and bench press repetition test) measurement program based on the NFL Combine program to compete in the selection of candidates for the Senior World Championship. All players were categorized into 1 of the 3 position groups based on playing position: skill players, big skill players, and linemen. Japanese players were additionally categorized into selected and nonselected players for the second tryout. The NFL Combine candidates had significantly better performance than selected Japanese players on all variables except on performance related to quickness among the 3 position groups. Compared with nonselected players, selected Japanese skill players had better performance in the 40-yard dash and bench press test and big skill players had better performance in the vertical jump, broad jump, and 40-yard dash. Selected and nonselected Japanese linemen were not different in any measurements. These results showed the challenges in American football in Japan, which include not only improving physical performance of top-level players, but also increasing the number of football players with good physical performance.

Training Patterns of Wheelchair Basketball Players in Turkey

Science.gov (United States)

Tatar, Yasar

2008-01-01

The aim of this study was to analyze technical drills, warm-up and cool-down exercises used by wheelchair basketball players of the Turkish league in relation to training sessions. 33 male wheelchair basketball players participated in the study (mean age 26.6[plus or minus]5,95 years). All players reported that they used warm-up exercises before…

Prospective study of injury in volleyball players: 6 year results.

Science.gov (United States)

Pastor, M F; Ezechieli, M; Classen, L; Kieffer, O; Miltner, O

2015-01-01

The volleyball game has a high complexity and thus entails a lot of strain to the players. Due to this high and different training and competition strain comprehensive and individual training plans should be developed with competing training objectives in order to prevent injuries. The aim of the study was to analyse prospectively over six seasons the acute and overuse injuries of a German male professional volleyball team. The study included 34 male national league players from season the 2007/08 to 2012/13. All players received a sport medicine examination and a functional diagnosis before each season. Based on the results the players received an individual training plan. The players suffered 186 injuries. The prevalence of acute injuries was 1.94 per player and overuse injuries 0.64 per player. The incidence of acute injuries was 3.3/1000 h volleyball and overuse injuries 1.08/1000 h volleyball. The largest number of injuries was found in the spine. The players had most likely minor injuries. The players had significantly fewer injuries in their second season (1.92) than in their first season (3.25; p= 0.004). It could be concluded that volleyball is a sport with a relative low prevalence of injuries compared to other team sports. The prevalence of injury is 2.58 per player. Due to an injury a player dropped out 16.91 days per season. An individual training program seems to reduce the incidence of injury.

Investigating the Nutritional and Recovery Habits of Tennis Players

Directory of Open Access Journals (Sweden)

James A. Fleming

2018-04-01

Full Text Available In this study, the nutritional and recovery habits of tennis players pre-, during, and post-match-play were investigated. Seventy tennis players completed a bespoke nutrition and recovery habits questionnaire, with questions related to the following areas: match preparation, intra-match nutritional habits, situation dependent variables, and post-match nutrition and recovery. On match day-1, the consumption of balanced meals consisting of carbohydrate (CHO, fat and protein, with some micronutrient considerations were reported by 51% of players. On match-days, CHOs were prioritised prior to match-play with CHO dominant meals consumed by the majority of players. During matches, all players adopted a nutritional strategy, with water (94%, banana(s (86% and sports drinks (50% commonly used. Carbohydrate rich nutritional aids, including sports drinks (80% and energy gels (26% were utilised more readily during long matches (>2 h. The day after match-play, 39% of players reported the consumption of “nothing specific”. Multiple post-match recovery strategies were adopted by 80% of players, with foam rolling (77%, ice baths (40%, protein shake intake (37% and hot baths (26% most used. Findings indicate highly variable eating and recovery habits in tennis players pre-, during and post-match-play, with scope for improved practices.

Investigating the Nutritional and Recovery Habits of Tennis Players.

Science.gov (United States)

Fleming, James A; Naughton, Robert J; Harper, Liam D

2018-04-03

In this study, the nutritional and recovery habits of tennis players pre-, during, and post-match-play were investigated. Seventy tennis players completed a bespoke nutrition and recovery habits questionnaire, with questions related to the following areas: match preparation, intra-match nutritional habits, situation dependent variables, and post-match nutrition and recovery. On match day-1, the consumption of balanced meals consisting of carbohydrate (CHO), fat and protein, with some micronutrient considerations were reported by 51% of players. On match-days, CHOs were prioritised prior to match-play with CHO dominant meals consumed by the majority of players. During matches, all players adopted a nutritional strategy, with water (94%), banana(s) (86%) and sports drinks (50%) commonly used. Carbohydrate rich nutritional aids, including sports drinks (80%) and energy gels (26%) were utilised more readily during long matches (>2 h). The day after match-play, 39% of players reported the consumption of "nothing specific". Multiple post-match recovery strategies were adopted by 80% of players, with foam rolling (77%), ice baths (40%), protein shake intake (37%) and hot baths (26%) most used. Findings indicate highly variable eating and recovery habits in tennis players pre-, during and post-match-play, with scope for improved practices.

Generative Agents for Player Decision Modeling in Games

DEFF Research Database (Denmark)

Holmgård, Christoffer; Liapis, Antonios; Togelius, Julian

2014-01-01

This paper presents a method for modeling player decision making through the use of agents as AI-driven personas. The paper argues that artificial agents, as generative player models, have properties that allow them to be used as psyhometrically valid, abstract simulations of a human player......’s internal decision making processes. Such agents can then be used to interpret human decision making, as personas and playtesting tools in the game design process, as baselines for adapting agents to mimic classes of human players, or as believable, human-like opponents. This argument is explored...... in a crowdsourced decision making experiment, in which the decisions of human players are recorded in a small-scale dungeon themed puzzle game. Human decisions are compared to the decisions of a number of a priori defined “archetypical” agent-personas, and the humans are characterized by their likeness...

Beneficial Long Communication in the Multi-Player Electronic Mail Game

NARCIS (Netherlands)

De Jaegher, K.J.M.

2015-01-01

In the two-player electronic mail game (EMG), as is well-known, the probability of collective action is lower the more confirmations and re-confirmations are made available to players. In the multi-player EMG, however, as we show players may coordinate on equilibria where they require only few of

PPARα gene variants as predicted performance-enhancing polymorphisms in professional Italian soccer players

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Proia P

2014-12-01

Full Text Available Patrizia Proia,1 Antonino Bianco,1 Gabriella Schiera,2 Patrizia Saladino,2 Valentina Contrò,1 Giovanni Caramazza,3 Marcello Traina,1 Keith A Grimaldi,4 Antonio Palma,1 Antonio Paoli5 1Sport and Exercise Sciences Research Unit, 2Department of Biological, Chemical and Pharmaceutical Sciences and Technologies, University of Palermo, Palermo, Italy; 3Regional Sports School of CONI Sicilia, Sicily, Italy; 4Biomedical Engineering Laboratory, Institute of Communication and Computer Systems, National Technical University of Athens, Athens, Greece; 5Department of Biomedical Sciences, University of Padova, Padua, Italy Background: The PPARα gene encodes the peroxisome proliferator-activator receptor alpha, a central regulator of expression of other genes involved in fatty acid metabolism. The purpose of this study was to determine the prevalence of G allele of the PPARα intron 7 G/C polymorphism (rs4253778 in professional Italian soccer players. Methods: Sixty professional soccer players and 30 sedentary volunteers were enrolled in the study. Samples of venous blood were obtained at rest, in the morning, by conventional clinical procedures; blood serum was collected and total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and triglycerides were measured. An aliquot of anticoagulant-treated blood was used to prepare genomic DNA from whole blood. The G/C polymorphic site in PPARα intron 7 was scanned by using the PCR-RFLP (polymerase chain reaction restriction fragment length polymorphism protocol with TaqI enzyme. Results: We found variations in genotype distribution of PPARα polymorphism between professional soccer players and sedentary volunteers. Particularly, G alleles and the GG genotype were significantly more frequent in soccer players compared with healthy controls (64% versus 48%. No significant correlations were found between lipid profile and genotype background. Conclusion: Previous results

Motivating Middle School Readers: The Graphic Novel Link

Science.gov (United States)

Edwards, Buffy

2009-01-01

Middle school students are not reading for pleasure as frequently as they formally have, due to the influx of video games, cell phones, MP3 players, and other electronic device. This is not even to mention the common stresses of the average middle school student. Current research on reading motivation finds that as children move from upper…

Decomposition of Multi-player Games

Science.gov (United States)

Zhao, Dengji; Schiffel, Stephan; Thielscher, Michael

Research in General Game Playing aims at building systems that learn to play unknown games without human intervention. We contribute to this endeavour by generalising the established technique of decomposition from AI Planning to multi-player games. To this end, we present a method for the automatic decomposition of previously unknown games into independent subgames, and we show how a general game player can exploit a successful decomposition for game tree search.

Mental Toughness Attributes of Junior Level Medalist Badminton Players

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Varghese C. Antony

2016-10-01

Full Text Available The study aims to compare the mental toughness attributes between medalist and non-medalist badminton players and between male and female players. Participants were 15 male and 15 female badminton players aged between 13-19 years (M= 15.71, SD=2.82. Mental toughness questionnaire of Tiwari and Sharma was administered and the data were analyzed by using descriptive statistics and t-test. Medalist players have exhibited higher mean values on self-confidence, attention control, motivation and goal setting attributes. Overall mental toughness of medalists was higher 180.80±17.15 than non-medalists 170.25±20.10. Comparison analysis showed significant difference between medalists and non-medalists on mental toughness attributes: Self-confidence (SCO: p=0.001<0.05, medalists scored (M±SD=31.33±2.10 higher than non-medalists; motivation (MOT: p=0.006<0.05, medalist scored higher (M±SD=33.50±4.07; goal setting (GSE: p=0.044<0.05, medalists scored significantly higher (M±SD=33.55±4.11 than non-medalists. Other attributes did not show any significant difference between medalist and non-medalist players. When compared with gender, no significant difference was observed on mental toughness attributes except attention control (ATNCON: p=0.044<0.05, female players scored (M±SD=38.97±3.08 higher than male players. The findings confirm that mental toughness is a desired attribute which differentiates a medalist and non-medalist player. Connaughton et al., (2007 stated that elite competitive athletes possess better mental toughness. Medalist players displayed better self-confidence than the non-medalists as supported by Kuan and Roy (2007, Loehr (1986. Motivation helps players to achieve their best and enhance mental toughness (Connaughton et al., 2008; Mohammad et al., 2009. Goal setting determines successful performance Weinberg and Weigand (1993, Weinberg (2003. It was concluded that medalist badminton players showed better mental toughness

A Survey on Common Injuries in Recreational Badminton Players

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A Muttalib

2009-11-01

Full Text Available The aim of this descriptive study is to determine the incidence of injuries among recreational badminton players. We evaluated 86 recreational badminton players in the city of Malacca; 35 were excluded for fitting the exclusion criteria. The average recreational badminton player was 36.13 years old and had been playing badminton for the past 17.84 years at a frequency of 2.11 times per week. 39.21% of the recreational badminton players complained of recent injuries in relation to playing badminton. Our data showed that the most common injury sustained by recreational badminton players was pain and stiffness at the shoulder joint. None of the injuries sustained by the players in our data were serious enough to warrant any form of surgical intervention. We conclude that badminton is a sport of relatively low risk and that the majority of related injuries were chronic overuse injuries.

Incidence of tinnitus in mp3 player users.

Science.gov (United States)

Figueiredo, Ricardo Rodrigues; Azevedo, Andreia Aparecida de; Oliveira, Patrícia Mello de; Amorim, Sandro Pereira Vasconcellos; Rios, Artur Guedes; Baptista, Vanderlei

2011-06-01

Exposure to loud noise is one of the main causes of tinnitus. To analyze the incidence of tinnitus in mp3 player users and non-users. One hundred subjects aged from 15 to 30 years were enrolled, 54 of them were regular mp3 player users and 46 were not. Patients with continuous tinnitus for at least 6 months completed the Tinnitus Handicap Inventory (THI) and were tested with high frequency audiometry and transient-evoked otoacoustic emissions (TAOE). A cross-sectional cohort study. The incidence of tinnitus in non-users was about 8 %; in mp3 player users it was about 28 %, a statistically significant difference. Hearing thresholds at 8 kHz were significantly higher in tinnitus patients that used mp3 portable players.TAOE were reduced at 2 kHz in the users group. No statistically significant difference was found in the THI scores between the two groups. Tinnitus was more frequent in teenagers and young adults who regularly listen to mp3 music in players. Moreover, the incidence of tinnitus among mp3 player users was associated with higher hearing thresholds at 8 kHz and lower TOAE at 2 kHz.

Female Chess Players Outperform Expectations When Playing Men.

Science.gov (United States)

Stafford, Tom

2018-03-01

Stereotype threat has been offered as a potential explanation of differential performance between men and women in some cognitive domains. Questions remain about the reliability and generality of the phenomenon. Previous studies have found that stereotype threat is activated in female chess players when they are matched against male players. I used data from over 5.5 million games of international tournament chess and found no evidence of a stereotype-threat effect. In fact, female players outperform expectations when playing men. Further analysis showed no influence of degree of challenge, player age, nor prevalence of female role models in national chess leagues on differences in performance when women play men versus when they play women. Though this analysis contradicts one specific mechanism of influence of gender stereotypes, the persistent differences between male and female players suggest that systematic factors do exist and remain to be uncovered.

Perceptions of football players regarding injury risk factors and prevention strategies.

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Astrid Zech

Full Text Available Current approaches regarding injury prevention focus on the transfer of evidence into daily practice. One promising approach is to influence attitudes and beliefs of players. The objective of this study was to record player's perceptions on injury prevention. A survey was performed among players of one German high-level football (soccer club. 139 professional and youth players between age 13 and 35 years completed a standardized questionnaire (response rate = 98%. It included categories with (1 history of lower extremity injuries, (2 perceptions regarding risk factors and (3 regularly used prevention strategies. The majority of players (84.2% had a previous injury. 47.5% of respondents believe that contact with other players is a risk factor, followed by fatigue (38.1% and environmental factors (25.9%. The relevance of previous injuries as a risk factor is differently perceived between injured (25% and uninjured players (0.0%. Nearly all players (91.5% perform stretching to prevent injuries, followed by neuromuscular warm up exercises (54.0%. Taping is used by 40.2% of previously injured players and 13.6% of players without a history of injuries. In conclusion, the perception of risk factors and performed preventive strategies are inconsistent with scientific evidence. Future transfer strategies should incorporate the players beliefs and attitudes.

Performance following a first professional concussion among National Basketball Association players.

Science.gov (United States)

Yengo-Kahn, Aaron M; Zuckerman, Scott L; Stotts, Jeff; Zalneraitis, Brian H; Gardner, Ryan M; Kerr, Zachary Y; Solomon, Gary S

2016-09-01

Basketball is a physical game played on a hardwood floor among high-jumping athletes at risk for injury. It is currently unknown how sport-related concussion (SRC) affects player performance after injury among professional basketball players. The objective of this study was to explore the impact of SRC on basketball performance among National Basketball Association (NBA) players. A retrospective, archival cohort study was performed that compared NBA player performance following concussion to pre-concussive performance. A comprehensive NBA injury database, compiled from publically available sources, was queried for NBA players who suffered concussion from 2005-06 to 2014-15 (10 seasons). Intra-and inter-player analyses were performed against a matched control group of players who missed playing time for personal reasons. Following application of inclusion/exclusion criteria and a matching process, 51 concussed players and 51 control players were included in analysis. There were no statistically significant decrements in baseline to post-concussion performance metrics in intra-player or player vs. controls after 5 return games. Our findings suggest that at the NBA level, an athlete's performance in the initial 5 games following injury does not suffer from the after-effects of concussive injury. These results may be useful in counseling professional athletes following a concussion.