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1.
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   

2.
The aim of this study was to compare and evaluate the kinematics of baseball pitchers who participated in the 1996 XXVI Centennial Olympic Games. Two synchronized video cameras operating at 120 Hz were used to video 48 pitchers from Australia, Japan, the Netherlands, Cuba, Italy, Korea, Nicaragua and the USA. All pitchers were analysed while throwing the fastball pitch. Twenty-one kinematic parameters were measured at lead foot contact, during the arm cocking and arm acceleration phases, and at the instant of ball release. These parameters included stride length, foot angle and foot placement; shoulder abduction, shoulder horizontal adduction and shoulder external rotation; knee and elbow flexion; upper torso, shoulder internal rotation and elbow extension angular velocities; forward and lateral trunk tilt; and ball speed. A one-way analysis of variance (P ? 0.01) was used to assess kinematic differences. Shoulder horizontal adduction and shoulder external rotation at lead foot contact and ball speed at the instant of ball release were significantly different among countries. The greater shoulder horizontal abduction observed in Cuban pitchers at lead foot contact is thought to be an important factor in the generation of force throughout the arm cocking and arm acceleration phases, and may in part explain why Cuban pitchers generated the greatest ball release speed. We conclude that pitching kinematics are similar among baseball pitchers from different countries.  相似文献   

3.
Kinematic comparisons of 1996 Olympic baseball pitchers   总被引：1，自引：0，他引：1  
The aim of this study was to compare and evaluate the kinematics of baseball pitchers who participated in the 1996 XXVI Centennial Olympic Games. Two synchronized video cameras operating at 120 Hz were used to video 48 pitchers from Australia, Japan, the Netherlands, Cuba, Italy, Korea, Nicaragua and the USA. All pitchers were analysed while throwing the fastball pitch. Twenty-one kinematic parameters were measured at lead foot contact, during the arm cocking and arm acceleration phases, and at the instant of ball release. These parameters included stride length, foot angle and foot placement; shoulder abduction, shoulder horizontal adduction and shoulder external rotation; knee and elbow flexion; upper torso, shoulder internal rotation and elbow extension angular velocities; forward and lateral trunk tilt; and ball speed. A one-way analysis of variance (P < 0.01) was used to assess kinematic differences. Shoulder horizontal adduction and shoulder external rotation at lead foot contact and ball speed at the instant of ball release were significantly different among countries. The greater shoulder horizontal abduction observed in Cuban pitchers at lead foot contact is thought to be an important factor in the generation of force throughout the arm cocking and arm acceleration phases, and may in part explain why Cuban pitchers generated the greatest ball release speed. We conclude that pitching kinematics are similar among baseball pitchers from different countries.  相似文献   

4.
The purpose of this study was to quantify and compare kinematic, temporal, and kinetic characteristics of American and Korean professional pitchers in order to investigate differences in pitching mechanics, performance, and injury risks among two different cultures and populations of baseball pitchers. Eleven American and eight Korean healthy professional baseball pitchers threw multiple fastball pitches off an indoor throwing mound positioned at regulation distance from home plate. A Motion Analysis three-dimensional automatic digitizing system was used to collect 200 Hz video data from four electronically synchronized cameras. Twenty kinematic, six temporal, and 11 kinetic variables were analyzed at lead foot contact, during the arm cocking and arm acceleration phases, at ball release, and during the arm deceleration phase. A radar gun was used to quantify ball velocity. At lead foot contact, the American pitchers had significantly greater horizontal abduction of the throwing shoulder, while Korean pitchers exhibited significantly greater abduction and external rotation of the throwing shoulder. During arm cocking, the American pitchers displayed significantly greater maximum shoulder external rotation and maximum pelvis angular velocity. At the instant of ball release, the American pitchers had significantly greater forward trunk tilt and ball velocity and significantly less knee flexion, which help explain why the American pitchers had 10% greater ball velocity compared to the Korean pitchers. The American pitchers had significantly greater maximum shoulder internal rotation torque and maximum elbow varus torque during arm cocking, significantly greater elbow flexion torque during arm acceleration, and significantly greater shoulder and elbow proximal forces during arm deceleration. While greater shoulder and elbow forces and torques generated in the American pitchers helped generate greater ball velocity for the American group, these greater kinetics may predispose this group to a higher risk of shoulder and elbow injuries.  相似文献   

5.
Baseball     
The purpose of this study was to quantify and compare kinematic, temporal, and kinetic characteristics of American and Korean professional pitchers in order to investigate differences in pitching mechanics, performance, and injury risks among two different cultures and populations of baseball pitchers. Eleven American and eight Korean healthy professional baseball pitchers threw multiple fastball pitches off an indoor throwing mound positioned at regulation distance from home plate. A Motion Analysis three‐dimensional automatic digitizing system was used to collect 200 Hz video data from four electronically synchronized cameras. Twenty kinematic, six temporal, and 11 kinetic variables were analyzed at lead foot contact, during the arm cocking and arm acceleration phases, at ball release, and during the arm deceleration phase. A radar gun was used to quantify ball velocity. At lead foot contact, the American pitchers had significantly greater horizontal abduction of the throwing shoulder, while Korean pitchers exhibited significantly greater abduction and external rotation of the throwing shoulder. During arm cocking, the American pitchers displayed significantly greater maximum shoulder external rotation and maximum pelvis angular velocity. At the instant of ball release, the American pitchers had significantly greater forward trunk tilt and ball velocity and significantly less knee flexion, which help explain why the American pitchers had 10% greater ball velocity compared to the Korean pitchers. The American pitchers had significantly greater maximum shoulder internal rotation torque and maximum elbow varus torque during arm cocking, significantly greater elbow flexion torque during arm acceleration, and significantly greater shoulder and elbow proximal forces during arm deceleration. While greater shoulder and elbow forces and torques generated in the American pitchers helped generate greater ball velocity for the American group, these greater kinetics may predispose this group to a higher risk of shoulder and elbow injuries.  相似文献   

6.
Controversy continues whether curveballs are stressful for young baseball pitchers. Furthermore, it is unproven whether professional baseball pitchers have fewer kinematic differences between fastballs and off-speed pitches than lower level pitchers. Kinematic and kinetic data were measured for 111 healthy baseball pitchers (26 youth, 21 high school, 20 collegiate, 26 minor league, and 18 major league level) throwing fastballs, curveballs, and change-ups in an indoor biomechanics laboratory with a high-speed, automated digitising system. Differences between pitch types and between competition levels were analysed with repeated measures ANOVA. Shoulder and elbow kinetics were greater in fastballs than in change-ups, while curveball kinetics were not different from the other two types of pitches. Kinematic angles at the instant of ball release varied between pitch types, while kinematic angles at the instant of lead foot contact varied between competition levels. There were no significant interactions between pitch type and competition level, meaning that kinetic and kinematic differences between pitch types did not vary by competition level. Like previous investigations, this study did not support the theory that curveballs are relatively more stressful for young pitchers. Although pitchers desire consistent kinematics, there were differences between pitch types, independent of competition level.  相似文献   

7.
This study investigated ball release speed and performance kinematics between elite male and female cricket fast bowlers. Fifty-five kinematic parameters were collected for 20 male and 20 female elite fast bowlers. Group means were analysed statistically using an independent samples approach to identify differences. Significant differences were found between: ball release speed; run-up speed; the kinematics at back foot contact (BFC), front foot contact (FFC), and ball release (BR); and the timings between these key instants. These results indicate that the female bowlers generated less whole body linear momentum during the run-up than the males. The male bowlers also utilised a technique between BFC and FFC which more efficiently maintained linear momentum compared to the females. As a consequence of this difference in linear momentum at FFC, the females typically adopted a technique more akin to throwing where ball release speed was contributed to by both the whole body angular momentum and the large rotator muscles used to rotate the pelvis and torso segments about the longitudinal axis. This knowledge is likely to be useful in the coaching of female fast bowlers although future studies are required to understand the effects of anthropometric and strength constraints on fast bowling performance.  相似文献   

8.
张世强  张世泽 《体育与科学》2012,33(2):95-101,117
多年以来,运动史学家都在争论,何以棒球能在曾为大英帝国殖民属地的美国取得凌驾于板球的发展。板球在美国的迅速式微,无论对于棒球或板球研究来说,都堪称最令人困惑的问题之一。及至今日,棒球与板球关系背后仍然存在许多难解的问题。既有文献指出,板球在美国的发展不仅可以上溯至17世纪,直到1860年代,板球也仍为美国非常普及的运动;但吊诡的是,就在内战之后,当美国社会进入"镀金时代"之后,板球却逐渐式微,甚至沦为美国边缘运动。透过检视美国棒球与板球发展的历史,本文企图指出主流理论的问题,尝试针对美国棒球与板球发展消长的关系提供不同的解释。  相似文献   

9.
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   

10.
Abstract

Throwing performance is vital within the sport of cricket. However, little published evidence exists regarding methods to improve throwing velocity and/or accuracy in any cricket-playing population. This study, therefore, assessed the efficacy of progressive velocity throwing training on throwing velocity and accuracy in a cricket-specific test. Eighteen sub-elite male cricket players were assessed for maximal throwing velocity and throwing accuracy at four different throwing velocities relative to maximal throwing velocity. The participants were randomly assigned to either an intervention (n=9) or control (n=9) group. Both groups performed usual pre-season activities for 8 weeks, during which the intervention group performed two additional specific throwing training sessions per week. Maximal throwing velocity was re-assessed at 4 weeks and the progressive velocity throwing programme was adjusted accordingly. The 8-week progressive velocity throwing training significantly increased peak and mean maximal throwing velocity (P = 0.01). Absolute changes in peak and mean maximal throwing velocity were negatively and significantly correlated with initial maximal throwing velocity at 4 weeks (r=?0.805, P = 0.01 and r=?0.806, P = 0.01 respectively) but not at 8 weeks. No significant difference was observed in accuracy for either group at any time. This is the first published study to describe the effectiveness of a progressive velocity throwing training programme on throwing performance in a group of sub-elite cricket players. The addition of two specific throwing training sessions per week can increase maximal throwing velocity without detriment to throwing accuracy.  相似文献   

11.
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   

12.
The purposes of this study were to: (a) examine differences within specific kinematic variables and ball velocity associated with developmental component levels of step and trunk action (Roberton & Halverson, 1984), and (b) if the differences in kinematic variables were significantly associated with the differences in component levels, determine potential kinematic constraints associated with skilled throwing acquisition. Results indicated stride length (69.3 %) and time from stride foot contact to ball release (39. 7%) provided substantial contributions to ball velocity (p < .001). All trunk kinematic measures increased significantly with increasing component levels (p < .001). Results suggest that trunk linear and rotational velocities, degree of trunk tilt, time from stride foot contact to ball release, and ball velocity represented potential control parameters and, therefore, constraints on overarm throwing acquisition.  相似文献   

13.
Abstract

Previous research has shown that experts exhibit superior response selection and skill execution during performance in youth sport. The purpose of this study was to examine differences in cognitive and skill execution components of game performance in young baseball players (N = 159) with, varying levels of expertise. Three levels of expertise (low-, average-, and high-skilled players) were identified at each age level (7, 8, 9, and 10 years of age). Game performance was videotaped, and measures of skill execution (throwing accuracy, throwing force, fielding, catching, batting average, and batting contact) and cognitive components (positioning, decisions) were developed from observational analysis. The results indicated that baseball skill execution during game play maximally discriminated expertise levels.  相似文献   

14.
高水平女子铁饼运动员运动素质的研究   总被引：1，自引：0，他引：1  
运用文献法、调查法、数理统计法等研究方法,对13名我国健将级女子铁饼运动员的运动素质情况进行了研究,结果表明:①专项投掷速度对女子铁饼运动员专项成绩的影响最大,它对专项成绩的贡献率为56.58%.②对女子铁饼运动员专项投掷速度影响最大的是下肢爆发力,其次是躯干力量,下肢最大力量的影响相对较小;③专项投掷速度与下肢爆发力呈高度正相关、与躯干力量呈中度正相关、与下肢最大力量呈中度负相关.  相似文献   

15.
Physiological requirements of cricket   总被引：1，自引：1，他引：0  
Despite its long history and global appeal, relatively little is known about the physiological and other requirements of cricket. It has been suggested that the physiological demands of cricket are relatively mild, except in fast bowlers during prolonged bowling spells in warm conditions. However, the physiological demands of cricket may be underestimated because of the intermittent nature of the activity and the generally inadequate understanding of the physiological demands of intermittent activity. Here, we review published studies of the physiology of cricket. We propose that no current model used to analyse the nature of exercise fatigue (i.e. the cardiovascular-anaerobic model, the energy supply-energy depletion model, the muscle power-muscle recruitment model) can adequately explain the fatigue experienced during cricket. A study of players in the South African national cricket team competing in the 1999 Cricket World Cup revealed that, in a variety of measures of explosive ('anaerobic') power and aerobic endurance capacity, they were as 'fit' as South African national rugby players competing in the 1999 Rugby World Cup. Yet, outwardly, the physiological demands of rugby would seem to be far greater than those of cricket. This poses the question: 'Why are these international cricketers so fit if the physiological demands of cricket are apparently so mild?' One possibility is that this specific group of athletes are unusually proficient in a variety of sports; many achieved high standards of performance in other sports, including rugby, before choosing to specialize in cricket. Hence their apparently high fitness may simply reflect a superior genetic physical endowment, necessary to achieve success in modern international sports, including cricket. Alternatively, it could be hypothesized that superior power and endurance fitness may be required to cope with the repeated eccentric muscle contractions required in turning and in bowling and which may account for fatigue and risk of injury in cricket. If this is the case, the fitness of cricketers may be increased and their risk of injury reduced by more specific eccentric exercise training programmes.  相似文献   

16.
The purposes of this study were to: (a) examine differences within specific kinematic variables and ball velocity associated with developmental component levels of step and trunk action (Roberton & Halverson, 1984), and (b) if the differences in kinematic variables were significantly associated with the differences in component levels, determine potential kinematic constraints associated with skilled throwing acquisition. Results indicated stride length (69.3%) and time from stride foot contact to ball release (39.7%) provided substantial contributions to ball velocity (p < .001). All trunk kinematic measures increased significantly with increasing component levels (p < .001). Results suggest that trunk linear and rotational velocities, degree of trunk tilt, time from stride foot contact to ball release, and ball velocity represented potential control parameters and, therefore, constraints on overarm throwing acquisition.  相似文献   

17.
Despite its long history and global appeal, relatively little is known about the physiological and other requirements of cricket. It has been suggested that the physiological demands of cricket are relatively mild, except in fast bowlers during prolonged bowling spells in warm conditions. However, the physiological demands of cricket may be underestimated because of the intermittent nature of the activity and the generally inadequate understanding of the physiological demands of intermittent activity. Here, we review published studies of the physiology of cricket. We propose that no current model used to analyse the nature of exercise fatigue (i.e. the cardiovascular–anaerobic model, the energy supply–energy depletion model, the muscle power–muscle recruitment model) can adequately explain the fatigue experienced during cricket. A study of players in the South African national cricket team competing in the 1999 Cricket World Cup revealed that, in a variety of measures of explosive ('anaerobic') power and aerobic endurance capacity, they were as 'fit' as South African national rugby players competing in the 1999 Rugby World Cup. Yet, outwardly, the physiological demands of rugby would seem to be far greater than those of cricket. This poses the question: 'Why are these international cricketers so fit if the physiological demands of cricket are apparently so mild?' One possibility is that this specific group of athletes are unusually proficient in a variety of sports; many achieved high standards of performance in other sports, including rugby, before choosing to specialize in cricket. Hence their apparently high fitness may simply reflect a superior genetic physical endowment, necessary to achieve success in modern international sports, including cricket. Alternatively, it could be hypothesized that superior power and endurance fitness may be required to cope with the repeated eccentric muscle contractions required in turning and in bowling and which may account for fatigue and risk of injury in cricket. If this is the case, the fitness of cricketers may be increased and their risk of injury reduced by more specific eccentric exercise training programmes.  相似文献   

18.
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   

19.
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   

20.
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   

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