An overview of cricket ball swing

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.     

Athletes' career transition out of sport: a systematic review

The purpose of this study was to provide a systematic review of studies on athletes' career transition out of sport from 1968 until the end of 2010. A total of 126 studies were evaluated and reported in three sections: sample characteristics, research designs and correlates of athletes' career transition adjustment. Samples ranged from 1 to 1617. Investigators examined a wide range of competitive levels, both genders and various sports. Researchers have used qualitative (44%), quantitative (44%), and mixed-model (12%) designs. Variables correlated to athletes' career transition adjustment were categorized into factors related to career transition (e.g., self-identity) and available resources during the career transition process (e.g., social support). The discussion focuses on the current status of the study area, limitations in its knowledge, suggested practical implications (e.g., providing proactive support) and future research directions (e.g., examining athletes' retirement decision-making process).     

An evaluation of biomechanical measures of bowling action legality in cricket

Cricket bowling is traditionally thought to be a rigid-arm motion, allowing no elbow straightening during the delivery phase. Conversely, research has shown that a perfectly rigid arm through delivery is practically unattainable, which has led to rule changes over the past years. The current rule requires a bowler not to increase the elbow angle by more than 15°, thus requiring a measurement to confirm legality in “suspect” bowlers. The aims of this study were to evaluate whether the current rule is maintained over a range of bowlers and bowling styles, and to ascertain whether other kinematics measures may better differentiate between legal and suspect bowling actions. Eighty-three bowlers of varying pace were analysed using reflective markers and a high-speed (240 Hz) eight-camera motion analysis system in a laboratory. The change in elbow segment angle (minimum angle between the arm and forearm), the change in elbow extension angle with respect to the flexion–extension axis of a joint coordinate system, and the elbow extension angular velocity at ball release were measured. We found that bowlers generally bowled within a change in elbow extension angle of 15°. However, this limit was unable to differentiate groups of bowlers from those who were suspected of throwing in the past. Improved differentiation was attained using the elbow extension angular velocity at ball release. The elbow extension angular velocity at ball release may be conceptually more valid than the elbow extension angle in determining which bowlers use the velocity-contributing mechanisms of a throw. Also, a high value of elbow extension angular velocity at ball release may be related to the visual impression of throwing. Therefore, it is recommended that researchers and cricket legislators examine the feasibility of specifying a limit to the elbow extension angular velocity at ball release to determine bowling legality.     

Effect of different types of cricket batting pads on the running and turning speed in cricket batting

The aim of this study was to compare a batsman's running and turning speed during three runs while wearing either traditional batting pads or one of two models of newly designed cricket batting pads. Fifteen cricketers participated. The running and turning speeds were measured on three different days with players using the three pairs of batting pads for each trial in random order. The weights of the pads were 1.85 kg, 1.70 kg and 1.30 kg for P¹, P² and P³ respectively. Each player had to run three runs (3 × 17.68m), with the times recorded at the completion of each run, as well as the time to cover the distance from 5 m before and after the turn at the end of the first run. The fastest time from two trials for each pair of pads was retained for analysis. An analysis of variance (ANOVA) with repeated measures was used to determine the differences between the mean times of the three trials. The results showed no significant differences between the types of batting pads and the time to complete the run‐three‐runs test (P¹ = 10.67 ± 0.48 s; P² = 10.67 ± 0.43; P³ = 10.69 ± 0.44 s), the turning time (P¹ = 2.34 ± 0.18 s; P² = 2.32 ± 0.18 s; P³ = 2.35 ± 0.19 s) and to complete the third run (P¹ = 3.49 ± 0.44 s; P² = 3.53 ± 0.34 s; P³ = 3.51 ± 0.36 s). Of the 45 trials of three runs used for analysis, P, recorded the fastest time on 16 trials (36%), P² on 19 trials (42%) and P³ on 10 trials (22%). The results showed no significant differences in the running or turning speeds, although there may be some practical relevance to using the newly designed cricket batting pads.     

The position of the head and centre of mass during the front foot off-drive in skilled and less-skilled cricket batsmen

The aim of this study was to compare selected kinematic variables of the front foot off-drive in skilled and less-skilled cricket batsmen. High-speed digital cameras were used to record the three-dimensional kinematics of 10 skilled and 10 less-skilled right-handed batsmen when playing a shadow front foot off-drive to realistic projected video footage. Skilled batsmen were more likely to identify the type of delivery bowled. Seventy percent of skilled batsmen had preparatory feet or foot movement before committing to play forward, while only 20% of the less-skilled batsmen utilized this trigger movement. Throughout the drive, the head of the skilled batsmen was further forward of the centre base point than that of the less-skilled batsmen. This forward head position was associated with the tendency for the skilled batsmen's centre of mass to be further forward during the predicted bat–ball contact. There were no significant differences between groups in the shoulder angle, bat angle or bat speed during the different phases of the stroke. There was a tendency for the less-skilled batsmen to have a larger hip angle at contact. This study provides further understanding of the factors associated with skilled performance in cricket batting, which coaches should consider when training less-skilled performers.     

Out with the old,in with the new: how changes in cricket helmet regulations affect the vision of batters

The International Cricket Council recently introduced new regulations for helmets in cricket. Amongst other changes, these regulations limit batters from adjusting the gap between the peak and the grille, resulting in some controversy over whether the new helmet design reduces visibility of the ball. This study compared the visual field of individuals when wearing an old helmet that does not conform to the new regulations, and the equivalent replacement which does. The visual field of 10 male participants was tested whilst wearing an old and new helmet. The new helmet resulted in a significant reduction in the visual field of the wearer (M = 66.1 out of 76 points seen in the new helmet vs. 74.8 seen with the old helmet), with the restriction predominantly confined to the superior visual field. The new regulations do appear to restrict the visual field of batters, confirming the anecdotal reports of players. However, the majority of this restriction occurs in the superior field, suggesting that the impact on batting performance may be limited. The importance of considering the impact that new helmet regulations can have on vision, batting performance, and player safety is discussed.     

Visual-perceptual training with motor practice of the observed movement pattern improves anticipation in emerging expert cricket batsmen

ABSTRACT

This study addressed the paucity of evidence of whether visual anticipation can be improved in emerging experts in striking sports. Twelve emerging expert batsmen from a state cricket squad were equally randomised into intervention and control groups. They were pre-and-post tested on a video temporal occlusion test of a fast bowler, as well as transfer tests of different fast and slow bowlers. The intervention group received two sessions per week of point-light display temporal occlusion training with motor practice of the observed bowler’s action over a 4-week period. The control group completed only the testing phases. Batting averages before, during, and after the study were recorded for both groups. The intervention group, but not the control group, improved anticipation to significantly above chance level across pre-to-post-tests based upon pre-ball flight information. The intervention, but not the control, transferred their learning to anticipate significantly above chance level based upon pre-ball flight information across different fast and slow (spin) bowlers. Batting average of the intervention group was higher than the control group during the study. Findings indicate that the intervention can improve anticipation in emerging expert batsmen, beyond sport-specific practice. This improvement may benefit competition performance, but further evidence is required.     

Education in the Chinese national sport system: experiences of professional wushu athletes

Abstract

Within the Chinese national sport system, the government provides resources and funding to train athletes from a young age to become high-performance competitors. Though athletes are well supported to excel in their sport, during their years of intense physical training, athletes generally receive little to no formal education to prepare them for life outside of sport. The sacrifice of forgoing formal education to compete in elite level sport is not uncommon for athletes within centralized sporting systems and has been widely documented; however, there is little research that focuses on the impact of the team’s educational systems from the perspective of the athletes. To add to the growing body of research in this area, the authors utilized in-depth interviews to examine professional wushu athletes’ education experiences whilst training on their team. Thematic analysis of the findings revealed that athletes who committed themselves to sport training in the Chinese national system had to negotiate a number of factors related to time, motivation, social influences, and resources when it came to education and academia. Findings highlight the ways in which these athletes experience and come to terms with limited academic opportunities, preparation and support from their team and the training environment.     

An audit of injuries in six english professional soccer academies

Regulations now state that professional academies in the United Kingdom are required to substantially increase the volume of soccer training. This study assessed the current injury occurrence, providing an update to reports published prior to the introduction of the Elite Player Performance Plan (EPPP). 608 soccer players aged 11–18 years from six professional soccer clubs were prospectively monitored, recording injuries during the 2014–2015 season. An injury rate of 1.32 injuries per player/season was indicated with a mean time loss of 21.9 days per injury. The greatest time loss per injury was in the U14s-U15s, and the highest rate of severe injuries in the U15s. Strains and sprains were the most common injury type, with the knee and ankle the most frequently injured anatomical sites. Seasonal variation indicated two peaks in injury incidence, occurring in September and January. In comparison to a published audit prior to the inception of the EPPP, this study indicates that academy soccer players are three-times more likely to experience an injury. Given that time loss and injury severity also increased during periods that typically follow rapid growth, these players should be considered an important group for training load monitoring and injury prevention strategies.     

An integrated analysis of match-related fatigue in professional rugby league

This study examined the changes in external outputs, including metabolic power variables, and internal response whilst considering contextual factors on physical performance variables during rugby league match play. Physical performance (total distance, high-speed running and high-power distances, average metabolic power), heart-rate (percentage heart-rate peak and training impulse), collisions (attacking and defensive) and contextual (time in attack, time in defence, time out of play) data were collected from 18 rugby league players during 38 games throughout two National Rugby League seasons. Physical variables were highest in the first 10-min period of each half (P < 0.001). Heart-rate indices peaked in the second 10-min period and were lower during second half periods (P < 0.001). Few differences existed in collisions and contextual factors across 10-min periods. Physical variables were highest during the first 5-min period compared to the final (P < 0.001). There was no difference in heart-rate response, attacking collisions or contextual factors between these periods. Following the peak 5-min period in the match, there were reductions in physical, heart-rate, defensive collisions and contextual factors (P < 0.001). The data show temporal changes in physical performance, heart-rate response and collisions during rugby league match play, although these are affected by contextual factors.     

优秀运动员退役致因与应对的描述性研究——以参与第16届亚运会的中国优秀运动员为例

在亚奥理事会、中国奥委会的支持下,对第16届亚运会中国体育代表团541名参赛运动员进行了问卷调查.问卷以国际奥委会ACP项目调查问卷为基础,根据我国运动员实际情况做了适当调整与修改,问卷调查内容包含研究对象事实信息及问题,主要涉及退役诱因、退役意识和退役阻碍.采用频数、RC列联表、皮尔森卡方检验对问卷调查结果进行了分析.研究发现,退役诱因依次分别为运动水平下降、受伤、新生活计划和家庭义务.年龄可能是退役原因形成的重要因素.运动员的退役意识表现出:运动员角色认同程度高,退役准备意识强,对应对退役后的挑战态度积极.但目前缺乏针对现役运动员展开的退役培训计划或职业规划.运动员退役后职业过渡与转换的主要阻碍在于运动员实际知识、能力水平与学历不符.研究结果还显示,不同年龄、性别、教育水平和运动经历的运动员在退役原因,意识、阻碍方面有差异.     

深圳市职业女性体育健身现状调查与分析

采用文献资料、问卷调查、访谈、数理统计等方法,就深圳市职业女性对体育健身的认知程度、参与健身活动方式、健身活动项目选择以及影响其参与健身的因素等方面进行了调查、访谈,结果显示：深圳市职业女性在全面认识体育功能等方面存在着一些问题,并有针对性地提出了一些合理化建议。     

An experience sampling study of organizational stress processes and future playing time in professional sport

ABSTRACT

This study examined the relationships between daily cognitive appraisals of organizational events, affective responses, and coping. In addition, a 5-year longitudinal relationship between coping and performance outcomes at the senior professional level was assessed. Using an experience sampling method, professional academy rugby union players (N = 39, M_age = 17.23 years, SD = 0.87) completed daily diary measures of appraisals, affective responses, and coping over 5 weeks of training. Hierarchical linear modeling revealed that daily cognitive appraisals were related to daily affective responses and coping functions enacted by behaviours, after accounting for a series of within (e.g., time, day, week) and between-person (e.g., personality, key decision-makers) differences. Zero-inflated negative binomial regression revealed that coping related to eliciting support was associated with minutes played at the senior professional level five years later. This study extends theoretical knowledge of the within- and between-person relationships that explain organizational stress experiences. The findings suggest that some coping functions enacted by behaviours may be early indicators of future performance outcomes in professional sport.     

我国体育界民心工程中"满意度"的首例研究——以广州非奥运会项目体协的"满意度"调查研究为例

体育社团的工作绩效已成为"民心工程"的一部分,体育环境、体育生活"满意度"将会成为广州和谐社会指标之一。对广州市非奥运项目体育协会综合经济实力和"满意度"进行比较,以促进整个体育事业的和谐发展。     

浙江省高校中青年干部体育生活方式实证分析

采用文献资料、问卷调查等研究方法,对浙江省高校中青年干部体育生活方式进行调查,在此基础上分析影响高校中青年干部体育生活方式的因素,进而提出养成良好体育生活方式的对策,为浙江省教育厅的干部管理及高校中青年干部提高身体素质提供参考.     

An analysis of soccer referee experiences in France and the Netherlands: Abuse,conflict, and level of support

Referee and match official discontinuation in sport is an issue of relevance to sport managers and administrators. Despite this, it is an often-neglected area of sport management research. In this paper, a critical analysis of the discontinuation of soccer referees across two countries is provided, utilizing an intergroup conflict theoretical construct to frame the analysis, drawing on the concept of conflict resolution to consider solutions to the issues uncovered. The distribution and subsequent analysis of an online survey in both France and the Netherlands facilitated engagement with a total of 4,637 referees, comprising 3,408 from France and 1,229 from the Netherlands. Following the thematic analysis higher order themes related to aggression, abuse and support systems emerged. Referees reported that verbal abuse was a frequent occurrence, and that incidents of physical abuse were also evident, indicating a culture of abuse toward referees in both countries. Referees as an outgroup felt marginalized, as players, coaches and spectators form ingroups with shared objectives. Additional findings suggest that the support structures around the referees require strengthening at both local and national level, to address issues related to discontinuation. The authors conclude by discussing the implications of the research on the match official abuse related literature, as well as identifying suggestions for researchers and practitioners.     

影响广州市高校离退休知识分子生活质量的因素分析

通过对广州市高校离退休知识分子生活现状的调查,分析了他们生活质量中存在的问题,阐述了影响他们生活质量的诸多因素,从而使社会更加关注高校离退休知识分子的生活质量,同时为社区老年保健规划提供科学依据。     

河南省城市弱势群体的体质状况调研及生活习惯与运动行为分析

城市弱势群体的体质状况不容乐观，该群体在饮食理念、科学膳食方面整体表现不佳。弱势群体的体育活动是全民健身计划的一部分。对这一特殊群体的体育活动予以理论上的指导和行动上的支持，要倡导克服不良生活习惯和不良嗜好，杜绝恶习、陋习，保持良好心态，促进身心健康。     

普通高校篮球选项课教学改革实验研究

传统篮球教学模式已经不能适应现代教学形势发展的需要.通过实验提出突出组合练习的速成教学法来提高教学效果,验证了速成教学法比传统教学法有较大的优越性,可使学生在有限的教学时数内掌握篮球技术,为终身体育打下良好基础.