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1.
The surface on to which a bowler projects a ball in the game of cricket is made up of hard packed soil with sparse grass cover. This natural turf pitch is of fundamental importance to the play of the game and the quality of the surface is a prime concern of players, officials, commentators and spectators alike. A programme of research has been undertaken to identify the factors that lead to the construction of high quality cricket pitches. This work employed the technology of highspeed video analysis to monitor the performance of first class cricket pitches during county matches. A system for measuring the impact of a cricket ball on a pitch was developed, and over 3000 ball impacts analysed. This analysis enabled pitches to be characterized in terms of pace, bounce and consistency. Soil properties for the monitored pitches were identified and correlations were drawn between pitch performance and soil composition.  相似文献   

2.
A cricket pitch is a prepared strip of compacted soil and closely mown turf onto which the bowler projects the ball. The surface is of fundamental importance to the game and groundstaff seek to ensure that the ball rebound is of sufficient pace, bounce and consistency to promote skill in both the batsman and bowler. The scientific understanding of the factors that influence the playing quality of a pitch is incomplete and groundstaff often rely on experience and ‘rules of thumb’. A major programme of research was undertaken to determine the effectiveness of a range of pitch measurement apparatus that are perceived to provide indications of playing character. Over three seasons, 18 fieldwork visits were completed at 11 different first-class county grounds. Pitches were tested at the end of each match and direct assessments of pace, bounce and consistency were achieved by employing an artificial bowler and high speed video arrangement. Measurements of surface friction, hardness and restitution were also recorded. It was found that no single pitch measurement was able to provide a reliable indication of pace or bounce, but, when the measurements were combined in a simple Newtonian model, good predictions of pace were achieved. The study revealed a simple method by which groundstaff can predict pace during crucial stages in pitch preparation. However, the study also showed that bounce is affected by levels of pitch deformation and that development of impact models and bespoke measurement tools is needed to reliably predict variation in bounce.  相似文献   

3.
New cricket bats need to be ‘knocked in’ prior to use, but just what this process does to the surface fibres of the bat is unknown and unquantified. One quantitative measurement of knock-in is the resultant surface hardness of the bat, and this paper describes knock-in tests to determine the surface hardness following differing durations of knock-in. The design of a cricket bat knock-in machine is first described. This takes the form of a cradle in which a cricket bat can be secured horizontally and then traversed at constant speeds in two mutually perpendicular directions while at the same time being struck with constant force by a cricket ball. The traverses are driven by lead screws, the motors of which can be independently switched on or off. The traverse distance can be varied with adjustable limit switches and relays that reverse the direction of rotation of the lead screws when activated. The cricket ball is attached to a rod that is lifted cyclically by a cam against a coil spring extension, and then allowed to fall under that force to impact on the bat surface. The impact (knocking-in) force was measured by a previously calibrated strain gauge attached to the rod holding the cricket ball. By judicious setting of the limit switches, selected areas of the bat surface were continuously knocked in for periods varying from 1 to 4 hours. After knocking in, the surface hardness was measured in accordance with British Standard 373 using a penetrator designed in accordance with the same standard. Analysis of the load/penetration curves shows an increase in surface hardness with knock duration. Photographs of the cell structure of the surface wood, obtained using a scanning electron microscope, show that under knock-in conditions, the wood cells collapse to form a mesh-like hardened layer which increases in hardness with increase in knock-in duration.  相似文献   

4.
Six male cricket bowlers (mean - s x ¥ : age 23.5 - 1.3 years; height 1.83 - 0.04 m; body weight 826 - 20 N) performed their typical bowling action at a set of stumps positioned at standard pitch length (20.1 m). A specially designed force platform rig allowed the correct positioning of two force platforms to be achieved beneath an outdoor polyflex runway (0.017 m depth) for each player's delivery stride pattern. For the back foot, the peak vertical ground reaction force was 1.95 - 0.08 kN (2.37 - 0.14 BW) and the braking force was 0.77 - 0.12 kN (0.94 - 0.16 BW). For the front foot, the peak vertical force was 4.80 - 0.92 kN (5.75 - 0.98 BW) and the braking force was 2.93 - 0.56 kN (3.54 - 0.67 BW). The mean peak vertical loading rate for front foot contact was 205 - 52.8 kN·s -1 (249 - 64 BW·s -1 ) with mean values ranging from 81 to 446 kN·s -1 (98 to 540 BW·s-1). The range for back foot contact was much smaller, 25-70 kN·s -1 (30-85 BW·s -1 ), with a mean of 41.7 - 7.10 kN·s -1 (50.6 - 8.6 BW·s -1 ). Mean peak impact occurred 24 ms after touchdown for the back foot and 16 ms after touchdown for the front foot. At impact, mean peak loading rates were greater for the front foot at 246 kN·s -1 (298 BW·s -1 ), with a range of 80-483 kN·s -1 (98-534 BW·s -1 ), than for the back foot at 65 kN·s -1 (79 BW·s -1 ), with a range of 40-84 kN·s -1 (49-110 BW·s -1 ).  相似文献   

5.
Six male cricket bowlers (mean +/- s(mean): age 23.5 +/- 1.3 years; height 1.83 +/- 0.04 m; body weight 826 +/- 20 N) performed their typical bowling action at a set of stumps positioned at standard pitch length (20.1 m). A specially designed force platform rig allowed the correct positioning of two force platforms to be achieved beneath an outdoor polyflex runway (0.017 m depth) for each player's delivery stride pattern. For the back foot, the peak vertical ground reaction force was 1.95 +/- 0.08 kN (2.37 +/- 0.14 BW) and the braking force was 0.77 +/- 0.12 kN (0.94 +/- 0.16 BW). For the front foot, the peak vertical force was 4.80 +/- 0.92 kN (5.75 +/- 0.98 BW) and the braking force was 2.93 +/- 0.56 kN (3.54 +/- 0.67 BW). The mean peak vertical loading rate for front foot contact was 205 +/- 52.8 kN x s(-1) (249 +/- 64 BW x s(-1)) with mean values ranging from 81 to 446 kN x s(-1) (98 to 540 BW x s(-1)). The range for back foot contact was much smaller, 25-70 kN x s(-1) (30-85 BW x s(-1)), with a mean of 41.7 +/- 7.10 kN x s(-1) (50.6 +/- 8.6 BW x s(-1)). Mean peak impact occurred 24 ms after touchdown for the back foot and 16 ms after touchdown for the front foot. At impact, mean peak loading rates were greater for the front foot at 246 kN x s(-1) (298 BW x s(-1)), with a range of 80-483 kN x s(-1) (98-534 BW x s(-1)), than for the back foot at 65 kN x s(-1) (79 BW x s(-1)), with a range of 40-84 kN x s(-1) (49-110 BW x s(-1)).  相似文献   

6.
ABSTRACT

Studies in several sports have shown the benefits of adapting the playing environment to fit junior players. Frequently the changes are pragmatic choices based on space constraints or existing line markings, or the result of simple scaling based on stature. In this study, a method of scaling the cricket pitch length is presented which is based on the age-specific size and performance of the bowlers and batters. The objective was a pitch length which enabled young bowlers to bowl good length deliveries while releasing the ball at a more downward angle, similar to elite bowlers. The steeper release angle has the benefit of reducing the sensitivity of the ball flight distance to the variability of ball release. Based on data from county standard under-10 and under-11 players a pitch length of 16.22 yards (14.83 m) was calculated, 19% shorter than previously recommended for under-11s in England. A shorter pitch also increases the temporal challenge for batters, encouraging a wider variety of shots and improved anticipation skills. Pitch lengths scaled in this way to fit the players’ abilities as they develop will enable a more consistent ball release by bowlers and more consistent temporal demand for batters.  相似文献   

7.
The time-course of physical recovery was determined after a 2-h 20-min, simulated cricket batting innings. Several vertical jump measures were assessed before (baseline), immediately after, 24 h after and 48 h after simulated batting. Six, male, academy cricketers (20 ± 2 years) completed a previously developed simulated batting innings (BATEX) at an outdoor net facility. At each assessment point, participants completed countermovement-jumps, squat-jumps and 5-repeated reactive-jumps on a contact mat. Compared with baseline, countermovement flight time was similar immediately after, but decreased 24 h after batting (-3.0 ± 1.8%, p < 0.05, effect size [ES] ± 90% confidence interval [CI]: -1.38 ± 0.52). At 48 h post, countermovement-jump flight time was similar to baseline. A similar pattern occurred in the squat-jump and the decrease in squat-jump flight time 24 h after simulated batting approached significance (p = 0.053, ES ± CI -0.80 ± 0.51). The 5-repeated reactive-jump measures (flight time, contact time and reactive-strength-index) did not decrease after simulated batting (p > 0.05), but there were moderate effect sizes calculated (0.64-0.96). These findings support the continued use of countermovement flight time to assess recovery in cricket, since full recovery of jump performance occurred 48 h after a simulated, prolonged and high intensity-batting century.  相似文献   

8.
Kinetic (3-D force plate), kinematic (videography) and temporal characteristics of backstroke turns by 20 male and 16 female swimmers were recorded to identify and describe key elements of backstroke turning performance. Data were recorded during a 50 m maximum effort swim in a 25 metre pool. A Pearson product moment correlation matrix revealed that the 5 m RTT was significantly correlated with anthropometric measures of height, mass, trochanteric height and age; kinetic measures of horizontal impulse and peak force; and kinematic measures of wall contact time and peak velocity. The stepwise multiple regression equation to predict 5 m RTT was: 19.6-0.75 trochanteric height-1.8 wall exit velocity-0.03 peak vertical force. Four key factors were identified from a principle components factor analysis--anthropometry and force, post-turn velocity, force preparation and rotational skills. Implications from the findings were that age-group backstrokers should 'hit the wall hard' with relatively extended legs to reduce swim distance and push-off deceleration; use minimal wall contact time, and maximise forces to develop high horizontal velocities in a streamlined position.  相似文献   

9.
Measuring the performance of a sports surface is typically derived from a series of field and laboratory tests that assess the playing properties under simulated game conditions. However, from a player’s perspective their own comfort and confidence in the surface and its playing characteristics are equally if not more important. To date no comparative study to measure playing preference tests has been made. The aim of this research was to develop a suitable method for eliciting player perceptions of field hockey pitches and determine the key themes that players consider when assessing field hockey pitches. To elicit meaningful unbiased human perceptions of a playing surface, an individual subjective analysis was carried out, using interviews and inductive analysis of the recorded player statements. A qualitative analysis of elite hockey players (n = 22) was performed to obtain their perceptions immediately after a competitive match. The significant surface characteristics that emerged as part of an inductive analysis of their responses were grouped together and formed five general themes or dimensions: player performance, playing environment, pitch properties, ball interaction and player interaction. Each dimension was formed from a hierarchy of sub-themes. During the analysis, relationships between the dimensions were identified and a structured relationship model was produced to highlight each relationship. Players’ responses suggested that they perceived differences between pitches and that the majority of players considered a ‘hard’ pitch with a ‘low’ ball bounce facilitating a ‘fast’ game speed was desirable. However, further research is required to understand the relative importance of each theme and to develop appropriate measurement strategies to quantify the relevant engineering properties of pitch materials.  相似文献   

10.
ABSTRACT

Conceptually, an efficient baseball pitch demonstrates a proximal-to-distal transfer of segmental angular velocity. Such a timing pattern (or kinematic sequence) reduces stress on musculoskeletal structures of the throwing arm and maximises ball velocity. We evaluated the variability of kinematic sequences in 208 baseball pitches. 3D biomechanical pitch analyses were performed on 8–10 fastball pitches from 22 baseball pitchers (5 high school, 11 collegiate and 6 professional). The kinematic sequence patterns – time of peak angular velocity of five body segments: pelvis, trunk, arm, forearm and hand – were measured. None of the pitches analysed demonstrated an entirely proximal-to-distal kinematic sequence. Fourteen different kinematic sequence patterns were demonstrated, with the most prevalent sequence being pelvis → trunk → arm → hand → forearm. Fewer than 10% of the pitchers performed only one kinematic sequence pattern across the sampled pitches. The variability of the kinematic sequence was similar in high-school pitchers and professionals. Previous studies report that deviation from the proximal-to-distal kinematic sequence is associated with increased injury risk. As a method of evaluating the efficient transfer of energy to the hand, the kinematic sequence may provide insight to injury risk in the future. The ideal kinematic sequence and ideal variability of the sequence when throwing have yet to be determined.  相似文献   

11.
Abstract

During the late-nineteenth century, imperial expansion increasingly produced what Louise Pratt terms ‘contact zones’ – ‘social spaces where cultures meet, clash and grapple with each other, often in contexts of highly asymmetrical relations of power’. Sport was one of the most visible spaces where this process took place. This paper uses the example of cricket in Samoa to demonstrate how different groups sought to control sport’s meaning amidst great uncertainty. Almost as soon as they began playing cricket, Samoans radically altered its method and meaning to create the distinctively Samoan game of kirikiti. This act established the cricket pitch as a ‘contested space’ between Samoans and foreigners, who were wary of kirikiti’s association with Samoan politics and customary exchange. As was the case in Samoa more generally, however, this struggle was not neatly divided between Samoans and foreigners. While missionaries and settlers portrayed the game as a threat, others – notably sailors and proponents of British influence – greeted it with relative enthusiasm. For their part, Samoans used the game to signal alignment with or against one or another Western power. Finally, Samoa’s growing ‘mixed-race’ community saw the game as a means of confirming their place in both the Samoan and European ‘worlds’.  相似文献   

12.
An overview of cricket ball swing   总被引:1,自引:0,他引:1  
The aerodynamic properties of a cricket ball have intrigued cricket players and spectators for years, arguably since the advent of the game itself. The main interest is in the fact that the ball can follow a curved flight path that may not always be under the control of the bowler. The basic aerodynamic principles responsible for the nonlinear flight or ‘swing’ of a cricket ball were identified decades ago and many papers have been published on the subject. Over the last 25 years or so, several empirical investigations have also been conducted on cricket ball swing, which revealed the amount of attainable swing and identified the parameters that affect it. Those findings are reviewed here with emphasis on phenomena such as late swing and the effects of humidity on swing. The relatively new concept of ‘reverse swing’, how it can be achieved in practice, and the role in it of ‘ball tampering’, are also discussed in detail. In particular, the ability of some bowlers to effectively swing an old ball in the conventional, reverse and the newly termed ‘contrast’ swing mode is addressed. A discussion of the ‘white” cricket ball used in the 1999 and 2003 World Cup tournaments, which supposedly possesses different swing properties compared to a conventional red ball, is also included. This is a current overview of cricket ball swing rather than a detailed review of all research work performed on the topic. The emphasis is on presenting scientific explanations for the various aerodynamic phenomena that affect cricket ball swing on a cricket ground.  相似文献   

13.
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   

14.
Abstract

The purpose of this study was to examine variations in ground reaction forces and selected lower extremity kinematics during the stride and swing phases of batting. High speed photography (100 fps) employing direct linear transformation methodology and a force plate were used to record three-dimensional kinematic and kinetic data for 7 female fast pitch softball batters. Mean vertical forces (Fz) of the right or rear foot increased to approximately 1 BW during the stride. Once the left or forward foot made contact with the ground after completion of the stride, right Fz forces decreased to .43 BW while left Fz forces rapidly increased to 1.6 BW at contact. The mean decrease in right Fz forces from peak force until contact was 55%, and the ratio of left to right Fz forces; at impact was 3.67:1. Right mediolateral forces (Fx) were exerted laterally, away from the batter, and were responsible for initiating movement of the body toward the pitched ball. As the left foot made contact with the ground at completion of the stride, left Fx forces were exerted laterally toward the pitched ball. The reaction to these forces retarded the batter's forward momentum, increased stability, and caused the left hip and knee to extend as contact approached. Right and left anteroposterior forces (Fy) acted in opposite directions (right foot pushing backward, left foot pushing forward), and were responsible for rotating the hips and upper body in a counterclockwise direction toward the pitched ball. Horizontal angular deceleration of both thighs just prior to contact was due, in part, to a decrease in these forces. These data may prove helpful when attempting to identify atypical batting patterns, and when considering improvements in shoe design. In the latter instance, force production and stability may be enhanced by aligning the cleats along the lines of action of the applied resultant shear forces.  相似文献   

15.
《Sport in History》2013,33(2):280-298
This article focuses on the development of women's cricket in a West Yorkshire town – Brighouse – in the 1930s. It situates this subject within the context of the growth of women's cricket more generally, and goes on to explore the personality and uniqueness of women's cricket in the town. The article identifies key issues in the way that women's cricket was perceived at the time, particularly in the pages of the Brighouse & Elland Echo, the local newspaper. As such, it considers the novelty of the sport, the gender stereotyping that was an important aspect of newspaper coverage, the relationship between women's and men's cricket, and also the marketing of key fixtures.  相似文献   

16.
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   

17.
《Sport in History》2013,33(1):17-31
Cricket is perhaps the quintessential English game, evoking images of green fields and dreaming spires. ‘No other game’, writes Hughes, ‘captures the peace and tranquillity of an English summer afternoon quite like cricket.’ 1 1. G. Hughes, ‘The Veil of War’, in South African Cricket Union, A Century of South Africa in Test and International Cricket (Johannesburg, 1989), pp. 14–15. Just as cricket speaks of England at peace, so too, perhaps because of Newbolt's much-quoted ‘Vitai Lampada’, was it bound up with England and the way she saw herself at war. Inevitably when war descended upon England and her colonies, cricketers rallied and were rallied to the ranks. And wherever the fight took them, cricket went too. The Duke of Wellington watched his guards playing cricket at Enghien a few days before Waterloo and on the day after the battle of Chernaya in the Crimea a match was played between the Guards division and the ‘Leg of Mutton Club’, a team of officers from other regiments.2 2. G. Hughes, ‘The Veil of War’, in South African Cricket Union, A Century of South Africa in Test and International Cricket (Johannesburg, 1989, p. 14.

The Anglo-Boer War of 1899–1902 was no different. Former teammates were forced onto opposing sides and some fine cricketers were killed. Yet on more than one occasion it was the game of cricket that crossed the conventional boundaries of politics and warfare. It is no surprise, then, that with the conflict coming at a time when cricket had already established itself within the colonies of Southern Africa, cricket and war should become inexorably linked.  相似文献   

18.
ABSTRACT

This study sought to determine whether playing on a shorter cricket pitch would lead batters to make more appropriate decisions about whether to play front foot or back foot shots. Based on an analysis of the shots played by top order batters against seam bowling in county under-10 matches, an age-specific “good length” region between 5.0 yards and 6.5 yards (4.57 to 5.94 m) from the batters’ stumps was derived. This was where batters were uncertain whether to play on the front or back foot. It was then possible to define deliveries as “short” or “full” depending upon whether they bounced further from or nearer to the batter than the good length region. Club under-11 and county under-10 match data revealed that when playing on a 16-yard pitch batters played more back foot shots to short balls, and county batters also played more front foot shots to full balls compared with matches on the currently recommended 20- or 19-yard pitches. For batters, a shorter pitch should strengthen the coupling between the perception of delivery length and appropriate shot selection, and the increased task demand should lead to improved anticipation, both key features of skilled batting.  相似文献   

19.
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   

20.
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   

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