Fitness Testing Assignment: Rugby

Fitness Testing Assignment: Rugby - by Joanna Kelton

Contents

• Introduction
• Teams
• Energy Systems
• Physiological Demands of Rugby Union Players
• Physiological Testing of Rugby Union Players
• Conclusion
• References

Introduction

Rugby Union Football is a football code that enjoys worldwide popularity. It is the national winter sport of New Zealand, South Africa and Wales. Furthermore, it is widely played in other British and Commonwealth countries, as varied as Tonga, Australia and Ireland (Rugby Yearbook 1999). The growing popularity of Rugby has led to International events such as the World Cup where teams from all over the world compete (Nicholas 1997).

At the elite level, two forty minute halves are played with no stoppages apart from injury time outs (Nicholas 1997). According to recent time motion analyses, the ball remains in plays for a total of only 25 to 29 minutes (McLean et al 1992).

Similar to other field based team games, the physiological demands of rugby union are of an intermittent nature, and vary depending on the position played (McLean et al 1992). Quarrie and colleagues (1995), in a comprehensive review of the demands on the New Zealand Rugby players, have also suggested that the metabolic demands of the players may also vary with the environment, the level of play, the officiating style of the referee and the tactical course of the contest.

An understanding of the physiological demands on the players is necessary to develop a sports specific training protocol. The training programme can subsequently be developed to mimic the physiological conditions imposed by the game (Deutsch et al 1998). Often each position in the team has a slightly different energy requirement profile. It is imperative that these differences are addressed and training stimuli modified accordingly.

Teams

A rugby union team is comprised of 15 players; seven backs and eight forwards. In general terms, the forwards can be considered the ball winners and the backs as the ball carriers (Nicholas 1997). However, the specific position demands are more complex than this broad overview.

The forwards consist of a front row of two props and a centrally positioned hooker. The back row of forwards comprises two locks and two flankers. The number eight is the remaining forward. The forwards engage in scrums with the opposition. They are also involved in rucking and mauling for possession of the ball. Rucking is described as a contest for the loose ball on the ground, whereas a maul is a contest when the players remain standing.

Props are the cornerpieces of the front row. They spend the greatest proportion of the time in close physical contact with the opposition. They have limited need nor opportunity to run. The hooker aims to win possession at the set scrum and usually controls the line out throw in. The two locks complete the tight five forwards. As the name suggests they lock in behind the props and hooker to stabilise the scrum set up. They are involved in jumping at lineouts and generally involved in more loose play than the props or hooker. It is the responsibility of the remaining forwards, the flankers and the number eight, to gain and retain possession of the ball in open or loose play. They are responsible for aggressive tackling and driving in the rucks and mauls (Nicholas 1997).

The backs are traditionally the ball carriers. There are inside backs, centres, wings and full backs. The inside backs, or the half backs, are the scrum half and the fly half or stand off. They control and distribute possession of the ball gained by the forwards. Correct positioning for offence and defence is paramount for these players. The centres are also heavily involved in offence and defence and have a high proportion of physical contact with the opposition players. Finally, the wings and full backs are the fastest sprinters and rely heavily on a combination of skill and speed to carry the ball to the line to score (Nicholas 1997).

The roles of the different positions vary greatly. Therefore it would logically follow that their metabolic demand for energy would also vary. There are three different energy systems that contribute to greater or lesser degrees depending on the intensity and the duration of the exercise performed. McArdle et al (1996) states that there is considerable overlap between one mode of energy transfer and another. They further suggest that all energy systems are simultaneously active to various degrees. The adenosine triphosphate-creatine phosphate (ATP-CP), the lactic acid system and the aerobic system combine to provide all the energy requirements of the players.

Energy Systems

The ATP-CP or high energy phosphate system provides a rapid supply of energy from stored ATP or CP in the muscle (McArdle et al 1996). The ATP is composed of a molecule of adenosine and three phosphates. The phosphates are bound together with high energy bonds. In an enzymatically controlled reaction, the bonds are broken to release energy.

ATP ATPase ADP + Pi + ENERGY

In the presence of the enzyme ATPase, ATP breaks down to adenosine diphosphate, inorganic phosphate (P_i) and 7.3kcal of energy.

CP CPase C + P + ENERGY

Creatine kinase provides the catalyst for the hydrolysis of creatine phosphate. The energy provided by this reaction provides the energy for the phosphorylation of ADP back to ATP. The CP provides a small reservoir of energy (McArdle et al 1996).

This short term power source is vital for short sprints or explosive accelerations to make or break tackles. Both of these activities are intrinsic to rugby union. This immediate energy system may also be utilised for sharp shoves in the scrum or vertical jump in the lineout (Nicholas 1997).

The ATP-CP system is able to supply energy required for maximal activity of five to six seconds duration. After the high energy phosphates are depleted an alternate source of ATP must be found. The energy required to phosphorylate the ADP back to ATP is provided primarily by anaerobic glycolysis (McArdle et al 1996). Through a series of reactions, glucose or glycogen in muscle is broken down to pyruvic acid. In the absence of oxygen, the pyruvic acid accepts hydrogen ions and forms lactic acid. The lactic acid levels build up in a hypoxic environment. Blood lactate levels are a measure of the imbalance between lactate production and removal.

High levels of intramuscular lactic acid may impede performance by reducing the capacity for force production (Jenkins 1993, McLean et al 1992). It has also been postulated that muscles with a predominance of fast twitch fibres, such as the hamstring muscle utilised in sprinting, preferentially convert pyruvic acid to lactic acid due to the presence of the enzyme lactate dehydrogenase. This may elevate the lactate levels in sprint type exercise (McArdle et al 1996).

Should exercise persist beyond several minutes duration, the aerobic system provides further energy to the body. Oxygen becomes important in energy transfer reactions when it accepts hydrogen ions from glycolysis, beta oxidation or Krebs cycle reactions. Aerobic training is important for specific local adaptations, which may favour reduced production of lactate or more rapid removal of lactate (McArdle et al 1996).

Jenkins et al (1993) postulated that an aerobic endurance base for field game players resulted in an enhanced ability to recover from short high intensity bursts of exercise. The central adaptations of endurance trained athletes of increased heart contractility and blood volume combine with the peripheral adaptations of improved oxygen delivery through an increased capillary network and increased oxidative enzymes within the muscle fibres to reduce the accumulation of the lactate. The adaptations favour the enhanced ability to recover from frequent short bursts of high intensity activity, and therefore maintain high muscle performance for the entire game (Jenkins 1993).

Physiological Demands of Rugby Union Players

In order to evaluate the physiological demands of rugby union players, several authors have utilised time motion analysis (Deutsch et al 1998, McLean et al 1992). This type of analysis allows the measurement of the duration and frequency of each activity. McLean et al (1992) postulated that the video analysis would allow calculation of running speed, running duration, density of physical work and a work rest ratio. From these measurements they further suggested that a more accurate interpretation of the requirements of the game would be possible, including the different energy systems utilised by the different positions.

In a time motion analysis of the Five Nations International Rugby, McLean (1992) found average running speeds of between five and eight metres per second. The average duration of a passage of play was 19 seconds. The most frequent work rest ratios in this investigation were 1:1 or 1:1.9. In a similar study conducted on Australian elite colts players, Deutsch et al (1998) presented work rest ratios of 1:1.4 for the forwards and 1:2.7 for the backs. The mean work rest ratio in this investigation was 1:1.9, matching the ratio quoted by McLean (1992). The results of the Australian study also shows the percentage of time spent in various activities. This is summarised in Table 1.

The front row forwards include the props and locks, the back row includes the flankers and number eight. The inside backs are the halves and centres, the outside backs are the wingers and full back. The forwards spend more time standing still and in rucking, mauling, scrummaging and other static high intensity activity. The backs spend a greater proportion of time at a walking, cruising and sprinting pace. They are also involved in a greater amount of utility movements such as running backward or sideways or changing directions.

Deutsch et al (1998) also monitored heart rate during a colts game. They suggested that heart rate was an indicator of work output due to the linear relationship between heart rate and oxygen uptake at submaximal workloads. Their results showed that the percentage of time in high intensity activity was greater for the front and back row forwards than for the backs. In addition to this, heart rate monitoring showed that the backs spent more time in moderate and low level activities. These results complement the results from the time motion analysis.

McLean et al (1992) and Deutsch et al (1998) both assessed the blood lactate levels of participants as an indicator of the contribution of the work by the anaerobic glycolytic energy pathway. The blood lactate was measured at stoppages for injury or penalty kicks. This may not result in a true indication of the peak values for the blood lactate as the stoppages may not correlate with time of maximal anaerobic work by the subjects analysed. However, in the context of an elite level contest this represented the appropriate time to take the measure. Blood lactates of between 5.8 and 9.8 mM were reported (Deutsch et al 1998, McLean et al 1992). Deutsch et al (1998) further related the blood lactate levels to the position played. Forwards tended to sustain higher blood lactate levels. This would support the suggestion of a greater contribution from the anaerobic system for the forwards than the backs.

Most of the time spent in recovery (standing still, walking or jogging) was passive for the forwards, compared to a greater time in active recovery processes such as walking or jogging for the backs. An active recovery period increases the removal of lactates from the blood (Deutsch et al 1998). The more effective removal of the lactates with active recovery may explain the lesser values for the backs. Despite the variation between forwards and backs, with results ranging from 4.7 to 9.8 mM, all values are above the 4.0mM expected when the aerobic system is the primary contributor to the energy transfer in the body (McLean et al 1992). As these results may be understated due to the timing of the measurements taken, it would be reasonable to suggest that all the players had a significant contribution from the anaerobic system.

The relative contribution of the energy systems for a similar field game are 10 per cent from the ATP-CP system, 70 per cent from the anaerobic glycolytic system and 20 per cent from the aerobic system (McArdle et al 1996).

The combination of the time motion analysis, heart rate monitoring and the blood lactate measures indicate that there is a significant contribution of anaerobic glycolysis for all positions on the field during a game of rugby union. The results further suggest that the forwards rely to a greater extent on the anaerobic energy systems. Backs may have a greater contribution from the aerobic system. This aids to remove the build up of blood lactates and replenish the stores of creatine phosphate within the muscle. All players, to varying degrees utilised the power of the anaerobic system for brief periods of maximal exercise, but also the aerobic system to enhance recovery between the bursts of lactic acid accumulation.

Physiological Testing of Rugby Union Players

Aerobic Testing

Athletes engaging in prolonged activities must possess high levels of cardiovascular fitness (Williford et al 1999). The aerobic fitness is imperative to aid the recovery between short bursts of high intensity activity that are intrinsic to field games such as rugby union. The capacity of the aerobic energy system is best assessed by a measure of VO_{2 max}(Nicholas 1997, Paliczka et al 1987). VO_{2 max} is the maximal oxygen uptake by an individual (McArdle et al 1996). Laboratory tests have been developed to accurately measure this capacity. Although these tests are the most precise and reliable tests available, they are prohibitive in their application (McArdle et al 1996, Williford et al 1999). Laboratory testing requires extensive equipment and experienced personnel, both of which come at considerable expense. Often these tests are not available to coaches and athletes (Paliczka et al 1987). On this premise, various methods of field testing have subsequently been described. All the field assessments aim to predict VO_{2 max} from a submaximal test.

Laboratory testing may be performed using a treadmill, cycle ergometer or arm crank apparatus. The values attained through the different methods of testing vary according to the volume of muscle mass activated. The test values attained are specific to the testing (McArdle et al 1996). The highest values obtained for VO_{2 max} are using the treadmill apparatus. The velocity of the treadmill is incrementally increased during the test to the point where there is no concomitant increase in the uptake of oxygen. The subject must maintain high levels of motivation throughout the test and not retire from testing until the physiological fatigue has been achieved. There exist inherent dangers in testing to the point of VO_{2 max} that may be avoided by the use of the submaximal predictive alternatives (Lear et al 1999).

Various tests have been developed as valid and reliable alternatives to the expensive and inaccessible laboratory tests. These are usually submaximal tests that predict the VO_{2 max} from the results (McArdle et al 1996). The benefits associated with the implementation of the submaximal tests are that they are inexpensive and safe and easily administered to groups of people (Leger and Lambert 1982). This has obvious advantages in a team sport. Furthermore, the group based nature of the task may aid subject motivation.

The 20 metre multistage shuttle run test (MSRT) is one of the submaximal tests. It was originally described by Leger and Lambert (1982). The test involves repetitive running over a distance of 20 metres at gradually increasing speeds for five minutes. The pace is initially set at eight kilometres per hour and is increased by increments of 0.5 kilometres per hour every minute. The participants are guided by audio signals on a prerecorded tape or compact disc. As the pace increases, the subjects continue until they are no longer able to meet the demands of the test. They are excluded from the test if twice consecutively they fail to complete the 20 metre distance in the allotted time (Leger and Lambert 1982, Williford et al 1999).

The test is performed on a flat playing surface. To increase specificity, the surface should match the surface of the required playing field. To ensure test-retest reliability, potentially confounding variables such as time, wind and temperature should be recorded and attempts should be made to retest under standardised test conditions. The timed beeps are played from a prerecorded compact disc. Markers should be placed 20 metres apart and a total distance of 22 metres is recommended to ensure adequate run through distance.

The VO_{2 max} is predicted from the following equation:

Where V = velocity achieved in the 20 MSRT (Leger and Lambert 1982).

The 20 MSRT has been found to be reliable on test-retest (ICC=0.93) (Williford et al 1999). The validity of the test is determined by how closely the 20 MSRT accurately resembles the true value of VO_{2 max} determined by laboratory testing. Several authors have investigated this. Grant and colleagues (1995), McNaughton et al (1996) and Williford et al (1999) all reported that the 20 MSRT, despite slightly underestimating the laboratory determined values for VO_{2 max}, significantly correlated with the best estimate of the true value. It has been suggested that the efficiency of turning during the test may result in the lower predictions for VO_{2 max}. The subjects better able to turn economically and accelerate through the drive phase of the test may have performed better in the 20 MSRT than less efficient participants (Grant et al 1995).

The sport of rugby union involves repeated bursts of high intensity activity and many direction changes. It has previously been shown that although the 20 MSRT underestimates the true value of VO_{2 max}, this may be less evident in sports of an intermittent nature (StClair Gibson et al 1998). Williford and colleagues (1999) have suggested that due to the specificity of the measure of VO_{2 max} to the activity performed in its determination, the 20 MSRT may be particularly appropriate for field sports. The test involves acceleration, deceleration and rapid changes in direction, all of which are integral components of field games such as rugby union. The laboratory test of maximal oxygen uptake involves incremental increases that are steady with no periods of acceleration. The 20 MSRT may give a better indication of the aerobic capacity of the players for playing conditions on the field (Williford et al 1999). Therefore, the 20 MSRT is a valid, reliable and easily achievable alternative to the gold standard laboratory test.

Currently, the Australian Institute of Sport and the New Zealand Rugby Union utilise the 20 MSRT. Data from both sources are displayed below in Table 2.

The reporting of the level of shuttle as a score is all that is necessary to provide a relevant repeatable performance measure (Ellis et al 1998). The data from the Australian and New Zealand studies show variation between positions for the measure of aerobic fitness of rugby players. The props are the least aerobically fit of the positions. The New Zealand cohort shows the half back players (Inside backs) to have the greatest aerobic fitness, while the Australian data shows the back row forwards to be the fittest players (Jenkins and Reaburn 1998, Quarrie et al 1996).

Anaerobic Testing

Rugby Union is an interval or intermittent sport. The athlete is required to continually produce short bursts of high intensity work with minimal loss of power (Nicholas 1997). Each short burst of high intensity exercise depletes the stores of creatine phosphate and leads to the accumulation of lactic acid, hence utilising the anaerobic energy system. Players rarely get sufficient time to recover completely and achieve full resynthesis of the creatine phosphate (Jenkins and Reaburn 1998). The ability of the players to continue to produce high intensity efforts depends on the efficiency of the removal of substances produced in the sprint, which inhibit peak performance (Wadley and LeRossignol 1998).

The physiological testing of anaerobic capacity of rugby union players has been advocated by many authors (Dawson et al 1991, Jenkins and Reaburn 1998, Nicholas 1997, Quarrie et al 1995, Wadley and LeRossignol 1998). The testing procedure is designed to measure the ability of players to recover from bursts of high intensity exercise (Quarrie et al 1995). The repeated effort test protocol measures the ability of the players to resist fatigue while enduring similar demands, with respect to time and distance of sprint, as experienced in a game situation (Jenkins and Reaburn 1998).

In a rugby union match the work rest ratios have been shown to be between 1:1 and 1:1.19 (McLean 1992, Deutsch et al 1998). The test procedure should mimic these conditions as accurately as possible. In the repeated effort test procedure described by Dawson et al (1991), the work rest ratio approaches 1:6. The test involves eight to ten sprints of 35-40 metres with 30 second rest periods. The Australian Institute of Sport suggests a modified version of this protocol. Eight repeats of a 35 metre sprint are undertaken with recovery periods of approximately 24 seconds (Jenkins and Reaburn 1998). However the work rest ratio in this test procedure still approximates 1:4 which is considerably larger than the ratio demonstrated in match situations. The New Zealand Rugby project advocates testing over a distance of 70 metres, including several direction changes. The effort is repeated six times in three minutes (Quarrie et al 1995). This protocol yields a work rest ratio closer to that experienced in a match situation. Furthermore, the direction changes involved in the New Zealand test procedure more closely resemble the demands of a rugby union game, where running in a straight line for 35 metres, as examined by the Australian protocol, is a desirable, yet unlikely event. However, the total distance covered by the participants in this test is 70 metres. Given that the rugby pitch is only 100 metres in length, the total distance covered may not be a valid indication of the distance required in a single sprint effort in a rugby match.

According to Deutsch et al (1998), the average duration of a passage of play in rugby is 19 seconds. Presuming the participant was engaged in a running activity for this time, then the protocol advocated by the New Zealand project most closely resembles the demands of a rugby match situation. The direction changes incorporated in this test are also more closely related to the realistic game situation.

Each repetition of the test consists sprinting a distance of 5 metres, changing directions and returning to the start. The participant is then required to sprint 10 metres and back to the start. Finally, the athlete is required to sprint a distance of 20 metres and back to the start position. Repetitions began every 30 seconds. The unused portion of the 30 second time block was utilised for rest. The faster the test was completed, the greater the rest time available. This may equalise the faster and slower sprinters. According to Wadley and LeRossignol (1998), faster sprinters use a greater portion of the available creatine phospate stores and hence have lower remaining creatine phosphate levels than slower sprinters. If equal rest periods for all sprinters are used, the faster sprinters will have less creatine phosphate available for subsequent sprint efforts than the slower players will. The overall time of 30 seconds used by the New Zealand Rugby test protocol may provide a means for more equal starting levels of creatine phosphate. In a match situation, the faster sprinters are the back line players (Nicholas 1997). In a video analysis of the physiological demands of rugby union players, Deutsch et al (1998) presented work rest ratios of 1:1.4 for the forwards and 1:2.7 for the backs. These ratios demonstrate an increased rest time for the faster back line players. The test protocol advocated by the New Zealand rugby project allows the backs increased rest time and thus more accurately mimics the true demands of the sport.

The test for repeated sprint ability is aimed at reflecting the demands of high intensity passages of play (Wadley and LeRossignol 1998). The anaerobic capacity test reported by Quarrie and colleagues (1995) most accurately reflects the physiological demands of a rugby union game. As it involves 30 second periods of activity for all players, regardless of sprint speed, it may be implemented to examine the anaerobic capacity of all team members on a single test occasion, hence rendering it easy to apply and time efficient for the coaching staff.

The New Zealand Rugby project anaerobic capacity test scores are calculated using a fatigue index as follows:

The players unable to complete six repetitions of the test are penalised by the final component of the equation, which will be greater than one, should the number of repetitions completed be less than six. The numerical value of the fatigue index will then be increased (Quarrie et al 1995).

The data from the New Zealand Rugby Injury and Performance project is detailed in Table 3.

According to the testing by Quarrie and colleagues, the fatigue indices calculated varied with the positional roles of the players. The scrum half and fly half (Inside backs) had the lowest index of the backs and the hookers recorded the lowest scores for the forwards. This is consistent with the requirements for these positions as described earlier in the paper. In the first class rugby players, the backs demonstrated significantly lower indices than the forwards (Quarrie et al 1996).

Normative preseason data for the repeated test protocol as described by the Australian Institute of Sport is provided in Table 4.

From the data collected on the Australian players, it appears that the tight four forwards (props and locks) had a higher index than all the other positions (Jenkins and Reaburn 1998).

Specific Rugby Testing

Various other physiological tests have been described for the assessment of rugby union players. These include sprint tests, agility tests, push ups, bench press and abdominal strength tests (Carlson et al 1994, Jenkins and Reaburn 1998, Maud 1983, Nicholas 1997, Quarrie et al 1995, 1996).

The ability to sprint is undeniably an important fitness component of rugby union (Nicholas 1997). Test procedures to assess this capacity have been described over short distances from standing or rolling starts (Carlson et al 1994, Quarrie et al 1995). However, the previously described aerobic and anaerobic tests for the players both involve a component of sprinting. The sprint speed may be calculated from the fatigue index test by timing the player over the 20 metre distance.

Several authors also advocate the use of agility test protocols for the players (Carlson et al 1994, Quarrie et al 1995). However the investigation into the New Zealand cohort found no significant differences between positions (Quarrie et al 1996). It would seem that there was insufficient evidence to determine the importance of agility to rugby union due to the difficulty in differentiating between positions and levels of performance (Nicholas 1997, Quarrie et al 1996). Furthermore, the aerobic and anaerobic test procedures previously described both involve a component of agility as they comprise several sharp turns within the tests. The agility of the player may be tested as an intrinsic and inseparable component of the prior assessment procedures.

Push-ups, bench press and abdominal strength are tests of upper limb and trunk strength and stability. Strength is a vital component of rugby union, particularly for the forwards who spend more time in static scrummaging and mauling situations (Nicholas 1997). Maud (1983) performed an investigation into the upper body strength of forwards and backs on an amateur team. Not surprisingly, forwards were able to bench press a significantly greater amount than the backs. Pushups, performed at a constant cadence, were assessed by Quarrie et al (1995) as a test of upper body muscular endurance. No significant differences between positions were demonstrated (Quarrie et al 1996). The specificity of this test to rugby union is questionable due to the lack of evidence to suggest that there is a positional influence on the pushup ability of the players.

The Australian Institute of Sport promotes the assessment of abdominal strength for rugby union players (Jenkins and Reaburn 1998). It is commonly agreed that abdominal strength is crucial to the maintenance of correct posture and to the prevention of injuries (Jenkins and Reaburn 1998). They suggest that abdominal strength and control may be assessed with the use of a pressure biofeedback system and a regime of isometric abdominal muscle actions. The abdominal strength test has recently been introduced and no normative data can be provided for the players (Jenkins and Reaburn 1998). The abdominal muscle action to support the lumbar spine and maximise core stability is a complex issue. The assessment needs to be done on an individual basis by a skilled assessor. This prohibits the easy application of the test to a team situation, except at the most elite levels where such a person may be employed. Although the theoretical basis of the test is sound, the successful application of it may be beyond the scope of the rugby team.

The development of explosive leg power is vital for all participants of rugby. The forwards require power in the line outs and scrummage situations. The back line players need the ability to accelerate over short distances and to make and break tackles (Nicholas 1997). One test of explosive leg power is the vertical jump test (Carlson et al 1994, Nicholas 1997). As the backrow forwards are required to jump during the lineout, the specificity of the test for these players is increased.

The Vertec is a popular device for assessment of jumping ability (Young et al 1997). It consists of a free standing pole and a series of plastic vanes that can be displaced by the fingers in a vertical jump. The Vertec is portable and can be used on the appropriate playing surface. Standing jump with a Vertec has been demonstrated to be reliable on test-retest (ICC = 0.94) (Young et al 1997).

Vertical jump height has been reported in various rugby populations. The data collected for the US national rugby team players was done using a Vertec (Carlson et al 1994). The mean values are reported in Table 5.

Carlson and colleagues (1993) suggested that the vertical jump allowed discrimination between backs and forwards. These findings are consistent with those of Quarrie et al (1996) who reported that the front row forwards had the lowest vertical jump height. The values for the New Zealand cohort, measured using an ultrasonic vertical jump height tester are displayed in Table 6.

The studies by Carlson and colleagues (1993) and Quarrie et al (1996) investigate the performance characteristics of first grade players. The vertical jump heights reported by Maud (1983) on an amateur rugby side show no such trends between forwards and backs, and relatively lower values than the values obtained by more skilled players. It may be suggested that as the skill of the side is increased, then so is the difference between the positional roles of the players.

Conclusion

From analysis of the physiological demands of rugby union, appropriate fitness testing procedures can be instituted. The test procedures should mimic the demands imposed by the game for the most accurate assessment of the players. Rugby union is an intermittent high intensity sport. The players rely upon anaerobic and aerobic energy systems. In addition, leg power is an integral component of the game for players of all positions. Field testing of these components of fitness may be performed in order to ensure specificity of the test to game conditions. Test procedures that are easy to apply are valid and reliable alternatives to expensive gold standard laboratory tests. These include the 20 MSRT for the aerobic system, the repeated effort sprint test for the recoverability of the anaerobic system and vertical jump using a Vertec, for the assessment of leg power. The results of the test procedures provide a means for the tailoring of training programmes for the athletes, as well as quantifiable results for psychological and motivational value for the players.

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