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1.
This study addressed the question, what should baseball players focus their attention on while batting? Less-skilled and highly skilled (college) baseball players participated in four dual-task conditions in a baseball batting simulation: two that directed attention to skill execution (skill/internal [movement of the hands] and skill/external [movement of the bat]) and two that directed attention to the environment (environmental/irrelevant [auditory tones] and environmental/external [the ball leaving the bat]). Batting performance for highly skilled players was best in the environmental/external condition and worst in the skill/internal condition. Performance of less-skilled batters was significantly better in the two skill conditions than in either of the two environmental conditions. We conclude that the optimal focus of attention for highly skilled batters is one that does not disrupt proceduralized knowledge and permits attention to the perceptual effect of the action, whereas the optimal focus of attention for less-skilled batters is one that allows attention to the step-by-step execution of the swing.  相似文献   

2.
Abstract

The purpose of this study was to examine differences in knowledge representation and problem solutions in expert and novice youth baseball players. Ninety-four players in two age divisions, 7–8 years of age and 9–10 years of age, were assigned to three levels of expertise: high; average; and low skilled. Each subject participated in an interview session to elicit knowledge representation and solutions to five different defensive game situations. Interviews were transcribed and analyzed for content, solution to the problem, errors in problem solution, and qualitative trends. The frequency of advanced solutions to each of the five situations were analyzed in separate chi-square tests for age and expertise. Differences among the levels of expertise were found for the accuracy of solutions to three complex situations. Age was significant for only one situation. Patterns of knowledge content accessed during advanced and less advanced responses indicated both experts and novices were in a beginning stage of developing baseball knowledge structures. Errors in problem solutions indicated children had difficulty monitoring critical conditions and making correct inferences. Players' and teammates' ability to execute baseball skills seemed to influence the content and structure of tactical knowledge accessed during problem solution.  相似文献   

3.
Abstract

In this study we compared the kinematic features of the throwing motion between young baseball players of different age groups. Forty‐four Japanese baseball players aged 6.1 to 12.3 years who regularly played baseball, including pitchers and position players, had their throwing actions analyzed three‐dimensionally using high speed videography. Of this sample, 26 players aged above 9 years of age were categorized as the senior group, while the remaining 18 were categorized as the junior group. Senior group throwers had greater height and body mass, and produced a greater ball speed than junior group throwers. The throwing arm movement of senior group throwers was similar to that of adult skilled players. However, in the junior group throwers, the shoulder horizontal adduction angle was larger during the arm acceleration phase, and the maximum angular velocities of elbow extension and shoulder internal rotation occurred later than in senior group throwers. These results indicate that players aged above 9 years can acquire a mature throwing arm movement, while players younger than that will use an immature motion. A possible reason why these differences were shown is that the official baseball is relatively heavy for junior group throwers; they would be better advised to use a lighter ball in throwing practice.  相似文献   

4.
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.  相似文献   

5.
In this study we compared the kinematic features of the throwing motion between young baseball players of different age groups. Forty-four Japanese baseball players aged 6.1 to 12.3 years who regularly played baseball, including pitchers and position players, had their throwing actions analyzed three-dimensionally using high speed videography. Of this sample, 26 players aged above 9 years of age were categorized as the senior group, while the remaining 18 were categorized as the junior group. Senior group throwers had greater height and body mass, and produced a greater ball speed than junior group throwers. The throwing arm movement of senior group throwers was similar to that of adult skilled players. However, in the junior group throwers, the shoulder horizontal adduction angle was larger during the arm acceleration phase, and the maximum angular velocities of elbow extension and shoulder internal rotation occurred later than in senior group throwers. These results indicate that players aged above 9 years can acquire a mature throwing arm movement, while players younger than that will use an immature motion. A possible reason why these differences were shown is that the official baseball is relatively heavy for junior group throwers; they would be better advised to use a lighter ball in throwing practice.  相似文献   

6.
Abstract

The main purpose of this article was to review a series of studies (n=23) on physical characteristics, physiological attributes, throwing velocity and accuracy, and on-court performances of male handball players – amateur players, experienced players, professional players, and players on the national team. Five main findings emerged from our review: (1) Elite players are heavier and have higher fat-free mass than amateur players. (2) The maximal oxygen uptake of male players is between 50 and 60 ml · kg?1 · min?1. (3) Throwing velocity is higher by as much as 9% in elite male players compared with amateur male players. (4) Heart rates can rise above 160 beats · min?1 in male players during a game. (5) On-court distance covered in a game averaged approximately 4 km and ranged between 2 and 5 km, depending on playing position. Our methodological concerns based on the reviewed studies are: (a) a lack of on-court physiological data; (b) a lack of experimental/manipulative studies; (c) limited data on throwing accuracy; and (d) a lack of longitudinal studies. The practical implications include: (a) strength and power exercises should be emphasized in conditioning programmes, as they are associated with both sprint performance and throwing velocity; (b) speed and agility drills should also be implemented in conditioning programmes; and (c) specificity of training based upon the position of the player is of great importance when planning strength and conditioning programmes.  相似文献   

7.
Abstract

Twenty-one male freshmen baseball players at the University of Maryland were randomly placed in three groups of equal size. Two groups supplemented a baseball throwing program by specific overload training. One group threw weighted baseballs while the other used a pulley device to resist the mechanics of throwing. Training was carried out for a 6-week period. Both training groups experienced significant within-group increases in throwing velocity as a result of training, with no significant change in accuracy. However, no significant difference was indicated among training groups and a control group.  相似文献   

8.
This paper considers the kinematic characteristics of overarm throwing with particular emphasis on the techniques

of throwing and pitching in baseball. The technique is subdivided into: (1) sequential pattern of throwing,

(2) lead foot contact, (3) preparatory phase, (4) arm acceleration and (5) instant of ball release. Specific biomechanical

principles that underpin throwing and their application within baseball are identified. The paper

also presents a case study of the three-dimensional characteristics of throwing technique in cricket. The aim

was to compare the skill in cricket to that previously researched in baseball. The findings for throwing in cricket

are similar to those reported for baseball, indicating that there is a definite crossover in the rationale of how an

individual should throw specific to the demands of cricket and baseball. The differences noted - greater elbow

flexion at lead foot contact and less external rotation during the preparation phase - can be attributed to the

demands placed on the fielder and pitcher specific to their respective sports.  相似文献   

9.
Abstract

The purposes of the present study were to evaluate transfer of movement education training to new skill performance and to evaluate skill improvement as a result of movement education and traditional training. The subjects were 47 first grade students who were in one of two classes. Each physical education class received one 30-minute class and one 20-minute class per week for 20 weeks. Subjects were taught movement principles either by a movement education approach or by a traditional approach. Johnson's Throw and Catch Test (1962) and a batting test for distance were used as pretests. These same tests were repeated as post tests in addition to two other tests which measured performance on striking and kicking distance and accuracy. Teaching approach groups were not significantly different on the latter two tests which measured the transfer of training effect. Traditional learning was better than movement education in developing throwing, catching, and batting performance. These results suggest that when one's objective is to teach a specific skill within a relatively short time period, a command style with demonstration is better than movement education.  相似文献   

10.
ABSTRACT

The aims of this study were to (1) to explore attentional strategies in expert judo players and (2) investigate how attentional focus affects performance effectiveness and perceptions of workload in expert judo players during real competitions. Fourteen expert male judo players participated in the study. A simulated recall method was used following participants’ competition to explore contents of attention qualitatively. The data analysis process for the qualitative portion of the study was an iterative process between inductive and deductive analyses. Quantitative analyses of performance outcomes and workload were then associated with the qualitative findings. Qualitative results revealed that the focus of attention was dynamic and complex, with technical aspects of the movements as the highest identified focus. Quantitative analyses revealed that reporting a lower quantity of attentional cues and higher percentage of focus on opponent resulted in higher performance effectiveness and less perceptions of workload. This study indicates that cognitive control and automaticity may work in a synergistic manner for successful skill execution in expert performance.  相似文献   

11.
Abstract

The purpose of this study was to examine the development of skill competence and tactical sophistication during a games unit conducted following the features of sport education provided by Siedentop (1994). One team of six players was followed through a 30-lesson season of “Ultimate.” Using Gréhaigne, Godbout, and Bouthier's (1997) formula for an efficiency index, together with a number of other measures of skill and tactical competence, it was determined that these students made significant improvements in selection and execution dimensions of the game. Furthermore, lower skilled students did not feel marginalized within their teams and believed they had equal opportunities for improvement. The key reasons for developing competence in this setting were the sufficient length of the season to allow for significant practice opportunities and the consistent team membership throughout season, which allowed all players to develop a sense of usefulness. This curriculum model provides one way students can develop skills through a system of game playing, provided sport education units are structured to prevent the more skillful players from dominating the games.  相似文献   

12.
Abstract

The purpose of this study was to test the validity of the games for understanding model by comparing it to a technique approach to instruction and a control group. The technique method focused primarily on skill instruction where the skill taught initially was incorporated into a game at the end of each lesson. The games for understanding approach emphasized developing tactical awareness and decision making in small game situations. Two physical education specialists taught field hockey using these approaches for 15 lessons (45 min each). The control group did not receive any field hockey instruction. Data were collected from 71 middle school children. Pretests and posttests were administered for hockey knowledge, skill, and game performance. Separate analyses of variance or analyses of covariance were conducted to examine group differences for cognitive and skill outcomes. The games for understanding group scored significantly higher on passing decision making than the technique and control groups during posttest game play and significantly higher than the control group for declarative and procedural knowledge. The games for understanding group scored significantly higher on control and passing execution than the other groups during posttest game play. For hockey skill, there were no significant differences among the treatment groups for accuracy, but the technique group recorded faster times than the control group on the posttest.  相似文献   

13.
Abstract

Athletes frequently have to adapt their skills to fast changes of play, often requiring the flexible execution of a particular movement skill with either hand. To assess the influence of sport-specific expertise and extensive sport training on human laterality, a video analysis of regular basketball games was performed for professional, semi-professional, and amateur players to investigate how non-dominant hand use and proficiency change with increasing expertise. Our results showed that the right-hand (i.e. dominant hand) bias in basketball players is reduced with increasing expertise (i.e. competitive level). Accordingly, we found that professional players use their non-dominant hand more often and with greater success than semi-professional and amateur players. This was true for most of the basketball-specific skills. Based on these results, we assume that increasing amounts of bilateral practice can lead to a shift in task-specific manual preference towards a higher use of both hands in competition, as well as to a higher proficiency for non-dominant hand actions in particular. From an applied perspective, the more frequent use and higher proficiency of the non-dominant hand in professional basketball players, compared with amateurs, suggests that the context-specific and skilled use of the non-dominant hand is crucial for successful play at higher competitive levels in the sport of basketball.  相似文献   

14.
In baseball and softball, there is a rule that allows the home team to have the last at-bat and thus the final opportunity to win the game. However, in tournament play, this rule is often set aside and, instead, batting order is decided by other means (e.g. tournament rules, the flip of a coin). The purpose of this study was to examine the impact of the batting last rule on game outcome in NCAA men's regional tournament baseball. It was hypothesized that host (i.e. home) teams would win a greater percentage of the games in which they batted last compared with when they batted first. This hypothesis was not supported. Closer examination of the last inning of play showed home teams were no more likely to have won the game during their last bat than visitors playing other visitors. The results suggest that the batting last rule contributes minimally, if at all, to home advantage in NCAA tournament baseball.  相似文献   

15.
ABSTRACT

The aim of this study was to investigate the kinetic functions of the lower limbs at different hitting-point heights to provide key information for improving batting technique in baseball players. Three-dimensional coordinate data were acquired using a motion capture system (250 Hz) and ground reaction forces were measured using three force platforms (1000 Hz) in 22 male collegiate baseball players during tee-batting set at three different hitting-point heights (high, middle, and low). Kinetic data were used to calculate joint torque and mechanical work in the lower limbs by the inverse dynamics approach. The peak angular velocity of the lower trunk about the vertical axis was smaller under the low condition. The joint torques and mechanical works done by both hip adduction/abduction axes were different among the three conditions. These results indicate that hip adduction/abduction torques mainly contribute to a change in the rotational movement of the lower body about the vertical axis when adjusting for different hitting-point heights. In order to adjust for the low hitting-point height which would be difficult compared with other hitting-point heights, batters should focus on rotating the lower trunk slowly by increasing both hip abduction torques.  相似文献   

16.
The aim of this study was to examine the effect of intermittent high-intensity shuttle running and fluid ingestion on the performance of a soccer skill. Nine semi-professional soccer players volunteered to participate in the study. Their mean (± sx ) age, body mass and maximal oxygen uptake were 20.2 ± 0.4 years, 73.2 ± 1.8 kg and 59.1 ± 1.3 ml·kg-1 ·min-1 respectively. The players were allocated to two randomly assigned trials: ingesting or abstaining from fluid intake during a 90 min intermittent exercise protocol (Loughborough Intermittent Shuttle Test:LIST).This test was designed to simulate the minimum physical demands faced by soccer players during a game. Before and immediately after performance of the test,the players completed a soccer skill test and a mental concentration test. Performance of the soccer skill test after the 'no-fluid' trial deteriorated by 5% (P ? 0.05),but was maintained during the fluid trial. Mean heart rate, perceived exertion, serum aldosterone, osmolality, sodium and cortisol responses during the test were higher (P ? 0.05) in the 'no-fluid' trial than in the fluid trial. The results of this study suggest that soccer players should consume fluid throughout a game to help prevent a deterioration in skill performance.  相似文献   

17.
Abstract

Release velocity and accuracy are vital components of throwing performance. However, there is no published research on these parameters for throwing in cricket. In this study, we investigated the throwing performance of 110 cricket players from six different populations: elite senior males, elite under-19 junior males, elite under-17 junior males, elite senior females, elite under-19 junior females, and sub-elite senior males. Based on a specifically designed cricket throwing test, participants were assessed for (1) maximal throwing velocity and (2) throwing accuracy at maximal velocity and at three sub-maximal velocities. Elite senior males exhibited the highest peak and mean maximal throwing velocities (P≤0.001). Furthermore, the groups of males had significantly higher peak and mean maximal throwing velocities than the groups of females (P≤0.01). A speed–accuracy trade-off existed such that all groups demonstrated improved accuracy scores at velocities between 75% and 85% maximal throwing velocity compared with 50% maximal throwing velocity and 100% perceived maximal exertion. The results indicate that sex, training experience (years training), and training volume (training time per week) may contribute to throwing performance in cricket players. Further research should focus on understanding the mechanisms behind the observed differences between these groups. This is the first study to describe the inherent throwing profiles of different cricket playing populations. Potentially, we have identified stimulus material for future training developments.  相似文献   

18.
In baseball and softball, there is a rule that allows the home team to have the last at-bat and thus the final opportunity to win the game. However, in tournament play, this rule is often set aside and, instead, batting order is decided by other means (e.g. tournament rules, the flip of a coin). The purpose of this study was to examine the impact of the batting last rule on game outcome in NCAA men's regional tournament baseball. It was hypothesized that host (i.e. home) teams would win a greater percentage of the games in which they batted last compared with when they batted first. This hypothesis was not supported. Closer examination of the last inning of play showed home teams were no more likely to have won the game during their last bat than visitors playing other visitors. The results suggest that the batting last rule contributes minimally, if at all, to home advantage in NCAA tournament baseball.  相似文献   

19.
Abstract

The catcher has the most demanding position in the games of baseball and softball with no regulations on how many throws they make during game. It was the purpose of this study to describe the kinematics and kinetics of the throwing motion in catchers when throwing down to second base. It was hypothesised that younger and older catchers would display significantly different throwing kinematics and kinetics. Thirty-eight baseball and softball catchers volunteered to participate. Twenty participants were considered younger (aged 9–14, 10.95 ± 1.76 years, 151.11 ± 15.64 cm, 47.94 ± 18.84 kg) and 18 were deemed the older group (aged 15–23, 18.11 ± 2.61 years, 170.91 ± 8.67 cm, 74.88 ± 10.74 kg). Participants received a pitch and completed five accurate throws to second base in full catching gear. The average ball speed of the older catchers was 21 ± 3.58 meters per second (47 ± 8.02 mph) while the younger catchers averaged 17.2 ± 4.0 meters per second (38.6 ± 8.96 mph). Older catchers had greater shoulder elevation at ball release and significantly greater shoulder external rotation at foot contact and shoulder maximum external rotation than younger catchers. It is clear that chronological age plays a role in the throwing mechanics observed in catchers throwing down to second base, however the effects of these differences are not fully understood (i.e., skeletal maturity, experience, strength).  相似文献   

20.
Abstract

Nine- to 10-year-old children have difficulty playing baseball using adult rules because pitchers lack the ability to throw the ball over the plate with consistency and batters lack ability to hit erratically thrown balls. Thus a natural field experiment investigated a modification of adult baseball for 9- to 10-year-old children. Instead of one of the players on the opposing team pitching, the coach of the offensive team pitched to the batters. Teams in a league who played baseball by adult rules (traditional league) were compared with teams in a league who played the modified game (nontraditional league), and both these leagues were compared with 11- to 12-year-old teams (older league). Various offensive and defensive activities were recorded by two observers and satisfaction scores were obtained from the players after the games. More offensive and defensive activity occurred in the nontraditional league games than in the traditional and older league games.  相似文献   

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