A review of cricket fielding requirements

Cricket is played in three formats at elite level: Test, One Day and Twenty20. Fielding is an important component of cricket, as all players are obliged to field. However, there is a paucity of literature on fielding compared with that on batting and bowling. We review the available literature in terms of technical, mental, physiological and physical factors important to fielding, to identify knowledge gaps and better understand the performance requirements of fielding in cricket.

Internationally, three formats of cricket are played at the elite level: Test, One Day and Twenty20. [1] All players bat and field, while only some players bowl and one person keeps wicket. Dismissing a batsman can be achieved in different ways, some specific to fielders; hence, catching and throwing are vital skills. Common requirements for these skills are speed and accuracy. [2] As well as dismissing batsmen, the role of elders includes saving runs, particularly in the shorter formats of the game. Therefore, optimising the movements and skills required to successfully field can have an important influence on the game. However, despite the adage that 'catches win matches' , research into elding is sparse compared with that into batting and bowling. [3] e purpose of this review was therefore to investigate and critique the existing knowledge of fielding in cricket, with the intent of better understanding the performance demands of elding.

Methods
For the purpose of this review, fielding performance was divided into a number of components ( Fig. 1) which were systematically reviewed. Reviewed literature included peerreviewed articles and book chapters. The requirements of the wicket-keeper are not discussed here, as the demands of this position have been reviewed previously. [4] The literature search was conducted using search engines (PubMed, SportsDiscus and ScienceDirect). The search terms 'fielding', 'wicket-keeping', 'catching', 'cricket' and other related terms were used in various combinations to search for articles. The reference lists of articles found were assessed to extend the search. As elding was the focus of this review, articles speci cally focusing on the wicket-keeper were excluded from the review. Additionally, cricket-relevant chapters from edited books were included.

Technical
In cricket, the playing field is not of fixed dimen sions. According to the laws of the game, 'the playing area shall be a minimum of 150 yards (137.16 m) from boundary to boundary square of the pitch, with the shorter of the two square boundaries being a minimum of 70 yards (64.01 m)' . [5] Due to the large and varying size of the playing eld, the skills of elding in cricket will vary considerably depending on where elders are placed. Here, the elding positions have been categorised as close (e.g. slips and short leg), inner-circle and outer-circle (Fig. 2). Shilbury [6] researched the frequency of field ing skills for 25 defined positions, and the elding patterns of individual players of an ' A'-grade cricket team playing first-class multi-day cricket. e data were divided into four skill categories: elded ball, elded ball and throw, elded ball and under-arm return, and catches and attempted catches. e author reported the frequency and skills required in 25 fielding positions. The positions which featured the most were cover (12%), mid-o (10%) and mid-on (9%), respectively. Cover has traditionally been considered a position that requires good attacking skills, such as being able to move towards the ball, eld and throw quickly, o en from unbalanced positions. [6] However, only 13% of cover's elding contacts required attacking skills; the majority of actions were defensive and required practically no diving or lateral movements. This finding is not consistent with conventional wisdom. Shilbury's study is dated (1990), and included data from only six domestic games. Given the developments in the game since the 1990s, research based on a larger number of international matches would be more appropriate and useful. ese ndings will assist the development of assessment and training protocols for the di erent formats of the game at the highest level.
In One Day cricket, matches began to be played into the night, and the ball colour was changed from red to white to be seen better under oodlights. Scott et al. [7] investigated the e ect of light levels and ball colour on catching, particularly for slip fielders in simulated field conditions. Photoelectric timing gates were placed in front of a ball projection machine and lever micro-switches were placed on the thighs of the players to establish reaction times to balls projected at a speed of 20 m/s over a distance of 8.4 m. e speed was considered representative of the demands of slip-catching performance, and was the upper limit of speeds safe for use under laboratory conditions. Catching performance was scored using a scale adapted from Wickstrom, [8] which rated catches from 0 (no ball contact at all) to 5 (clean catch). A er performing a 2 (ball) × 3 (light level) analysis of variance (ANOVA), no signi cant e ects were noted for catching performance and movement initiation times for ball or light levels. e authors concluded that the change in ball colour or diminishing light levels were not detrimental to performance. However, the sample size was very small (n=5), which might have accounted for the lack of statistical signi cance. Also, the testing protocol required players to assume a standing position that may not be normal under game conditions. e e ect of a visual-perceptual training programme on elding in cricket has been investigated using a test-retest design involving a 6-week training intervention. [9] e tests involved an in situ elding test, and athletes were required to react (predict and move in the direction that the ball was hit) to a life-sized video projection of a batsman hitting strokes, with the video occluded at the point of ball contact. e video was lmed from the perspective of 3 di erent elding positions: extra cover, mid on and mid o . Moving in the correct direction for each video assessed decision accuracy. e training group underwent an add itional 3 perceptual training sessions per week in addition to the on-eld training programme undertaken by the control group. e training group performed significantly better than the control group in the two tests. It was concluded that while 6 weeks of regular oneld training may lead to improvements in fielding performance, greater advantages could be gained when this is combined with visual perceptual training sessions.
A fielder's ability to throw a ball over considerable distance with speed and accuracy, if aiming for a run out, requires excellent throwing technique. [10] The requirements are speci c for the di erent eld positions. e slips mostly intercept a fast moving ball coming o the edge of the bat and reaching them below chest height. [11] ey have little need for throwing long distances. In-elders require good reactive ability to catch a ball falling from above their heads and strong overarm throwing ability [3] to attempt run-outs. Out elders o en have to cover a considerable distance, so sprinting ability is vital, and they need to throw accurately over long distances. [6] Good techniques are not only essential to win matches; they also minimise the risk of injury. [2] Synchronised high-speed video cameras [11] have been used to study the biomechanics of throwing. Distinguishing di erent throwing techniques has led to the identification of important performance variables. [11] The relationship between over-arm throwing velocity and accuracy in elite and sub-elite cricketers was investigated using a speci cally designed throwing test. [8] A speed-accuracy trade-off was detected. Subjects improved accuracy scores at velocities of 75 -85% of maximal throwing velocity. Senior elite players performed better than other groups. No research into side-or underarm throwing in cricket has been found. Using the correct technique is crucial for success; the lack of empirical data in this area limits the development of optimal training programmes. For skills development, player selection and talent identi cation, it is important to test correctly for skill and movement e cacy. is can assist a coach to detect strengths and weaknesses in performance and to identify the speci c training needs of the individual. [12] Stretch and Goslin [12] devised a set of cricket skills tests, encompassing all components of the game. With regards to elding, the majority of runouts occur between 10 m and 35 m, [13] and these were the distances tested in the elding test ( Fig. 3). At point A, the elder was required to catch a thrown ball, over-arm throw at the target and then move as quickly as possible to point B. At points B, C, D, E, and F, the elder was required to pick a ball up from the ground and over-arm throw at the target; point G required a pick up and under-arm throw at the target, followed by a nal sprint to the target. e timer started when the elder touched the rst ball and ended when he had run through the target. A time penalty (3 s) was given if he dropped the balls or a throw did not go through the target at any time during the test. e authors and coaches also used their knowledge of the game to determine, sub jectively, the players' potential success in a match. [12] e validity of the elding tests was tested by comparing the objective tests to the subjective opinion of coaches. e relationship between the objective elding test scores and the subjective elding evaluation was low (r=0.47; p<0.05); however, the sample size was relatively large (n=155), hence the authors decided that the lower correlation was acceptable. e diagnostic utility of this test could be questioned, given the composite nature of the test i.e. many skills assessed within one test.

Mental
Cricket requires inordinate physical skill and mental aptitude, including the ability to concentrate intensely for very long periods, for which a high level of physical tness cannot fully compensate. [14] Fielders have to concentrate on every ball of the innings, regardless of their positions. ey have to be able to maintain concentration for the entire duration of an innings (ranging from approximately 90 minutes in a T20 innings to a total of 6 hours per day in a Test match), through changing conditions as play progresses through the day. However, studies on the mental aspect of cricket have focused on batting only; [15][16][17] no research, to the authors' knowledge, has addressed the mental aspects of elding.
Physiological e most prevalent approach to quantifying the physiological demands of cricket is time-motion analysis using global position ing satellite (GPS) units. Rudkin and O'Donoghue [18] performed 27 observations of a elder positioned at cover point, during rst-class multi-day games. ey used the CAPTAIN time-motion analysis system to de ne seven movement classes: stationary, walking, shu ing (rapid non-running movement of the feet), jogging, running, low-intensity fielding and high-intensity elding. It was found that the cover point elder spends the majority (94.2%; standard deviation (SD) ±2.4) of match time in stationary activity and walking, while high-intensity activities represented just 1.6% (SD ±0.8) of movement activity. It was concluded that rst-class elding entails less high-intensity exercise than other team sports such as hockey and soccer. However, the conclusions are of limited value, as only one elding position was analysed.
Time-motion studies could help develop knowledge of positional di erences in work load between the di erent formats of cricket, allowing conditioning coaches to prescribe game-speci c training programmes. [1] Petersen et al. [1,19,20] have conducted several studies using GPS technology, investigating physiological demands of performance in the three di erent formats of the game. Unlike in the study by Rudkin and O'Donoghue, [18] ve movement categories were established (standing/walking, jogging, running, striding and sprinting) and the three di erent cricket formats were investigated. Table 1 summarises time-motion analyses for each format of cricket. In summary, it seems that elding intensity is greatest in a T20 match and elders covered approximately the same distances in One Day and Test cricket.
Petersen et al. [19] tested the validity and reliability of three commercially available sports GPS units to monitor cricket-speci c movement patterns. ey found disparate and inconsistent measures for the validity and reliability of low-and high-intensity activities.
ey advised that conditioning coaches should be aware of the likely under-reporting of high-intensity activity and over-reporting of lowintensity e orts when using GPSs in training. All studies detailed thus far fail to document the physiological demands of the di erent elding positions because, generally, elders -without distinctionare compared with bowlers and batsmen.
Physical e physical aspects of performance have been investigated with respect to injury incidence and prevention, particularly for fast bowling and throwing, but little investigation into the physical aspects of elding has taken place. In this section, physical aspects such as anthropometry, strength, speed and aerobic and anaerobic tness will be considered.

Anthropometry
Several studies have investigated the anthropometric pro le of rstclass cricketers, [21][22][23][24][25] mostly by comparing groups of players, such as batsmen, bowlers or all-rounders. e measures used mass and stature measurement and the sum of seven skin folds (biceps, triceps, subscapular, supra-iliac, abdominal, thigh and medial calf). Portus et al. [25] extensively researched the characteristics of Australian players. However, these ndings are probably not valid globally given ethnic differences in stature. While other physical attributes would be considered when deciding where to place players in the eld, certain anthropometric characteristics may make players suited to speci c positions. Nevertheless, the anthropometry for specific fielding positions has not been explored.

Aerobic and anaerobic tness
With modern cricket, players can be expected to tour for up to eleven months of the year; therefore, physical tness is increasingly important. The only study [26] that focused specifically on the calori c energy demand of cricketers was performed in 1955, and its validity in representing the demands of modern players would seem problematic. More recent research has indicated that cricketers generally rely on aerobic energy supply and that the rates of energy expenditure of cricket are relatively low; with the exception to this being fast bowlers during a bowling spell [21,26] and elders sprinting a er the ball. is generalisation is supported by the ndings of time-motion analyses. [1,19,27] e multi-stage tness test is recommended to test aerobic power as it is inexpensive, easy to administer and applicable to many team sports with respect to the stop, start and change-of-direction movement patterns. [24] One study [14] showed that cricketers had a higher shuttle run number when compared with rugby union players, with a VO 2max of ~6 0 ml/kg / min. Johnstone and Ford [21] established physical fitness profiles of cricketers grouped into bowlers and batsmen (n=15) using this test. e authors recorded the number of completed shuttles (12.4; SD ±0.9), end heart rate (190.4 bpm; SD ±11.2) and predicted the VO 2max (54.9±3.7). e researchers Table 1. Summary of ndings from time-motion studies by Petersen et al. [19,20] Variable* Study Quantifying positional movement patterns in Twenty20 cricket [19] Comparison of player movement patterns between ODI and Test cricket [20] ODI Test concluded that the VO 2max results of cricketers were superior to that of the general population. [21] ese results are comparable with the normative data presented for cricket players in Physiological Tests for Elite Athletes. [25] Anaerobic tness has generally been tested using repeated sprint tests. Johnstone and Ford [21] found that the running speed for each of the groups was similar, although the bowlers achieved moderately better results (1.5%) in maximal repeated sprint tests than the batsmen. Sprint tests in cricket have typically varied in distance (10 -40 m); therefore, it is di cult to compare results between studies. Johnstone and Ford [21] recommended that the future assessment of cricket-speci c speed should use short distances of 5 -15 m, because these may be associated with higher levels of match-winning elding performance. However, sprint testing over a large range of distances may be justi ed because the size of the pitch that players will have to cover varies in distance depending on elding position.

Position
In summary, cricket players require a high level of aerobic tness in order to play for up to 6 hours per day, with intermittent, short bursts of high-intensity e ort that requires contribution from the anaerobic energy system. Whether these demands di er as a function of elding position has not been researched. It may be that a position such as slips with potentially less aerobic demands may bene t from greater doses of high-intensity reactive training. Nevertheless, given the length of the international cricket season and the tour demands of cricketers, superior aerobic tness will assist players in recovery and sustaining performance at the highest level.

Strength, power and speed
Upper body e results of studies on strength and power pro les of cricketers have, thus far, been ambiguous and seem to lack logical or face validity. Johnstone and Ford, [21] for example, measured upper-body strength and power using a medicine ball throw and timed press-up tests. ere were marked di erences between batsmen and bowlers; the batsmen were superior in the timed press-up tests, but the bowlers produced greater backward throws. However, the signi cance of these results and their relation to performance is unclear. ere is no research on speci c elding positional demands, nor have normative data for each elding position been established. Nevertheless, it appears that di erent strength requirements may be needed for di erent elding positions (e.g. the throwing demands of an out elder v. a slip elder).

Lower body
Leg strength and power are important for cricket elders as they contribute to the speed and agility required for elding. However, there has been little research on the lower-body strength pro le of cricketers. Johnstone and Ford [21] tested lower-body strength and explosive power using a counter-movement jump and repeated vertical jump test. e authors suggested that tests such as the counter-movement jump give an indication of slow stretchshortening cycle performance, and found that there were negligible di erences between bowlers and batsmen. Bourdon et al. [24] also recommended a series of tests for pro ling the physical tness of elite cricketers; the lower-body tests included a vertical double-leg jump, abdominal strength stage test, straight sprint speed (10, 20 and 40 m) and a run 3 agility test. While the abdominal stage test is lauded as particularly important for fast bowlers, the authors noted that batsmen and fielders would benefit from good abdominal strength during long periods in the eld or at the batting crease. e leg-power demands of elding are little understood; however, a study comparing cricketers with rugby players found no signi cant di erences in leg press, bench press and 35 m sprints. [14] For example, there is little logic in using only a vertical jump test when research and observation show that elders need to move in all directions and consequently need multi-directional lower-leg strength and power. Correctly assessing the multi-planar movement ability of elders should lead to better training programmes.

Conclusion
There is a paucity of scientific information on the performance demands of elding across all the areas of interest discussed in this review article, i.e. technical, physical, etc. ere seems to be little appreciation of the technical requirements related to di erent elding positions. From the scant literature available, it is possible to deduce that cricket elding is, in general, a low-intensity activity that requires intermittent bursts of explosive movement. However, conventional wisdom on several aspects of the game is not supported by scienti c evidence. Given that elding is an essential component to winning matches, the lack of research in this area is disconcerting. A systematic research programme covering all components of all game formats would be bene cial.
Existing knowledge could be complemented by obtaining the considered opinions and insights of coaches and players and by carrying out detailed video and notational analyses. e results would provide greater insight into the skill and movement requirements associated with the di erent eld positions. is information would also provide a framework for the design of elding-speci c assessments, which should enable the development of more focused training, conditioning and coaching protocols. is should enhance elding performance and contribute to the ultimate goal of winning matches.