Technical Analysis of elite male soccer players by position and success Paper
Since the early work of Reep and Benjamin (1968), many aspects of association football have been utilised by researchers within notational analysis. Several researchers (Reilly and Holmes, 1983; Luhtanen, 1988; Dufour, 1993) have however identified the lack of literature existing detailing the exact technical demands with regard to their relative successful performance between specific positions of play.
The purpose of the investigation was to deliver such a technical analysis of playing positions within elite level International football at the European Championships 2004. The data were gathered by a specifically designed notation system which collected qualitative data based on the relative successful execution of techniques performed, post event. Players were grouped into positional classes as goalkeepers, defenders, midfielders or strikers. A comparison was also made between the technical distributions of both a successful and unsuccessful team.
The Chi Squared statistical test was used to compare differences between the frequency distributions and the differences in technical ratings between positions and the successful and unsuccessful teams. Significance was accepted at the (p<0.05) level (Vincent, 1999). Significant differences (p<0.05) were found between the frequency distributions of all 3 outfield positions, but no significant differences (p>0.05) were found between the accumulated means of technique ratings across all of the performance indicators. Individual variable analysis however showed significant differences (p<0.05) occurred between specific performance indicators across positions.
No significant differences (p>0.05) were discovered between either the frequency distribution or the technical rating of outfield players between successful and unsuccessful teams. A significant difference (p<0.05) was however apparent between the frequency distribution of goalkeepers actions between successful and unsuccessful teams.
The study implicates that coaches must be selective of which players play within certain positions and that training sessions must be accurate to the specific needs of individuals and their position within a team.
The process of hand notation is an important tool, which can be used to inform the coaching process. Hand notation is a cheap, simple, accurate but time consuming method of notation (Hughes and Franks, 2004). It provides a coach with an objective view of the key elements of a performance. Notational analysis can provide many aspects of information to a coach. Hughes (1998) defined the 5 purposes of notational analysis:
1. Analysis of Movement;
2. Educational use for both coaches and players;
3. Tactical Evaluation;
4. Development of a data base/modelling;
5. Technical Evaluation.
Due to its structure of incorporating individual techniques within a team framework, association football provides a notational analyst with an ideal field for analysis. Within association football, the use of notational analysis enables coaches to improve aspects of their own team’s play, at both an individual or collective level and also to interpret the actions of any future opposition.
Reilly and Thomas (1976) adapted a methodology in order to analyse player’s movement, or more specifically work rate within different positional roles in a first division football team. Observations were made over the course of a season, incorporating a total of 51 competitive games, both home and away. Player’s movements throughout a game were subdivided into several distinct movement classifications. This allowed the individual movement characteristics of different positional roles to be established and therefore for accurate training strategies to be incorporated.
The use of feedback was identified by Franks (1997). Feedback can have an educational use for both players and coaches, as it is an important component of the coaching process. Franks stated that any improvement in performance is a consequence of task related feedback. Feedback can be provided before, during and after a skilled performance to both specific individuals and to whole teams alike.
A tactical evaluation of association football was achieved by Yamanaka et al., (1997) who performed a computerised notational analysis of 8 games in the 1994 World Cup Asian Qualifying matches. The respective playing patterns of the teams were analysed, with a particular emphasis upon the Japanese national team. This was achieved by entering 32 actions of players in relation to an 18 cell division of the pitch. From the data it was found statistically significant that Japan used dribbling more as a tactic (p<0.05), used more passes (p<0.01) and more frequently used a clearing kick (p<0.05).
Garganta (1998) suggested how the development of a soccer data base/model can be considered as a mediator between a theoretical and an empirical field. He states that it is important to understand a soccer team’s organisation and to observe a whole teams actions. Garganta explained how game modelling is acquiring greater importance in order to analyse performance trends and to prioritise any such problems of the training process.
A technical evaluation was achieved by Partridge et al., (1993). A specialised computer analysis system was developed, using 38 key events entered in real time by a trained analyst. The system was used to provide a comprehensive technical evaluation of performance by comparing the results of 2 distinct levels of performance, the 1990 FIFA World Cup and the 1990 World Collegiate Soccer Championships. From the results it can be inferred that collegiate coaches must be selective when presenting World Cup teams as an appropriate model of performance as many differences do occur, which makes any comparison invalid.
At International football level, where games are decided by small margins, the team that is superior in physiological and motor abilities will have the advantage (Reilly and Holmes, 1983). This places a high emphasis on a team at the elite level possessing high levels of technical ability.
Within the literature, there are very few examples of technical analysis, in particular skill analysis involving association football. In this respect, the following study is innovative in two ways:
i) By analysing at the exact technical requirements of each position
ii) By using qualitative data within a quantitative system.
1.1 Aim of Study
The aim of this study is to analyse every individual’s technical ability that competes in the European Football Championships of 2004. This measure will be based on a subjectively drawn continuum that analyses a player’s technical movement throughout the game.
It will be investigated if technical differences occur between player positions and between successful and unsuccessful teams.
Data will be gathered from matches within the European Championships of 2004, which were held in Portugal. This tournament has been chosen as it provides an ideal environment for a comparison to be made between elite level players competing in an elite sporting environment. Data will be collected using a hand notation system, in the form of a table. The table will consist of six columns: player number; technique performed; technique rating, pitch position, time of action and any outcome (if applicable).
The hypothesis states that there is a significant difference in the distribution of technique between the different playing positions and between successful and unsuccessful teams at the European Championships 2004.
Certain assumptions are considered during this study. It is assumed that all players selected are of international standard and that all players are competing in the tournament to win.
Limitations of the study that depict the nature and length of the investigation include the word limit imposed and the submission date. Variations from the tournament itself may also not give the data a true reflection of reality. Incidents such as injury to key players, conditions and the environment may impact on the manner in which a team or certain individuals perform. As the matches were all recorded from terrestrial television, some data cannot be collected due to its absence from the showing of action replays and other inappropriate footage (Winkler, 1996). The choice of some camera positions and angles also makes some forms of player identification difficult.
A de-limitation from our research design is that it is impossible to make broad generalisations from our data. The obtained data is so specific to the tournament and elite level players that any such generalisation would be inaccurate and invalid. The analysis is also produced in a very subjective manner using operational definitions and a likert scale, which may also not be universally agreed by people other than the researchers.
1.6 Definition of Terms
Technique: The method of performance of an individual against a normative scale.
Player Position: An individual’s role and function within a team’s structure.
2.0 Literature Review
2.1 Notational Analysis in Football
Some of the earliest analysis of association football was carried out by Reep and Benjamin (1968). They analysed over 3000 competitive games from 1953 to 1967 within top division English football and World Cup matches using a simple hand notation system. The position of player’s actions, the amount of passes before goals and the way in which possession was gained were all notated. From this extensive analysis it was reported that:
i. 80% of goals resulted from 3 passes or less
ii. 50% of goals result from regaining possession in the final attacking 1/4
iii. It takes 10 shots to score 1 goal
Many coaches and managers throughout the English game saw these results as an immediate formula for success. The transfer of these findings into a game situation saw the arrival and development of the traditional long ball game within British soccer.
The work of Reep and Benjamin was later taken on further by Bate (1988) in an attempt to disprove a modern day notion that maintaining possession of the ball was the key to accomplishment. From analysing games in the English 3rd division, right up to World Cup level competition, Bate concluded that in order to be a success, teams must portray the following characteristics in their play:
i. Play the ball forward as often as possible
ii. Reduce the number of square and backwards passes
iii. Increase the number of forward passes and forward runs
iv. Play the ball into the space behind the defenders as early as possible
From Bate’s (1988) analysis, it can be seen that the determinants of success across a wide range of football were relatively unchanged for a long period of time and that the notion of possession football was not the key to success.
Further characteristics of successful play were noted by Winkler (1996). He stated that good teams are capable of defending their own goal well as well as creating more goal scoring opportunities than the opposition. His findings were however contradictory to the research of both Reep and Benjamin (1968) and Bate (1988) by suggesting that successful teams should keep possession of the ball for longer, as opposed to getting the ball as forward as quickly as possible.
More recently Luhtanen et al., (2001) adapted a methodology from Luhtanen (1993) to study selected offensive and defensive variables of individuals within the European Championships of 1996 and 2000. The study aimed to examine if any correlation occurred between performance and final position reached in the tournaments. A computerised notation system was used to notate over 2000 actions per game. The actions of the individuals could then be calculated to give means for each of the teams per selected variable. France, who were the winners of Euro 2000 were found to be the highest ranked nation in passing, receiving the ball, running with the ball and tackling. Luhtanen et al. (2001) concluded that this consistent high ranking suggested that France were worthy winners of the tournament. The winners of Euro 1996 however, Germany, were not found to be the highest ranked in any selected variable. Luhtanen et al. (2001) explained this concept by stating that the Germans performed very ordinarily throughout the tournament, and a great deal of luck brought them success. The selection of performance indicators for use in the study may however have only been conducive to certain patterns and styles of play. Although these may have highlighted the attacking nature of France’s performance, they do not take into account factors such as levels of team cohesion and team organisational structure. It may have been high levels of factors such as these which brought the Germans success, not merely luck, as was stated in the review.
Luhtanen et al., (2001) summarised that comparisons between team performances across tournaments or time spans couldn’t be made absolute due to the numerous changes in team selections, opposition, tactics used and managerial changes.
2.2 Factors determining success within association football
Vast amounts of literature are apparent concerning the various aspects of a team’s performance, especially those, which bring success.
Hughes et al., (1988) developed a methodology to differentiate between successful and unsuccessful teams from the 1986 World Cup by examining the main characteristics of play when in possession of the ball. Successful teams were defined as those teams who progressed to the semi final stages, whereas unsuccessful teams were those who were eliminated after the 1st group stage. Analysis was conducted using 24 performance variables. It was found that successful teams have more touches in possession, had more shots at goal from within the penalty area and approached the final sixth of the pitch by playing predominantly in the central areas. Unsuccessful teams dribbled more and played the ball to the wide areas in their own defensive zones more frequently.
The findings of Hughes et al., (1988) study were contradicted by Ali (1988) who conducted a statistical analysis of patterns of play in 18 Scottish Premier Division matches. It was concluded that attacks which proceeded along either wing were more successful, rather than those which were played more centrally.
Teams using low pass combination moves combined with centrally based attacks were the factors deciding success in Bishovets et al., (1993) study of 52 World Cup matches. This manner of performance was related to winning teams have a more consistent and reliable understanding between players.
Pearce and Hughes (2001) conducted analysis of the perceived successful impact of substitutions in the 2000 European Championships. Data was gathered in the 15 minutes preceding a substitution and in the 15 minutes afterwards. Each performance variable was evaluated and ranked depending on its value of influence. This allowed a show of ratings along a continuum to be created, both of the individual substitute and of the team’s performance following the substitute’s introduction. Although it was found that 15 minutes of analysis did not produce enough data, midfield was seen to be the most hazardous player position in which to introduce a substitute, due to the high work intensities required immediately by the incoming player.
The idea of coding actions according to their difficulty and their success can also been seen in Rico and Bangsbo (1997) study of Denmark’s performance in the 1992 European Championships. Actions were noted according to the amount of pressure applied on the performer and conclusions were drawn from the results. The decline of Denmark’s passing in their final 3 games was put down to the increased pressure and closeness of the score line related to the latter stages of the tournament.
Dooan et al., (1996) conducted a further study to determine the factors, which promote success within soccer. The importance of playing at a high tempo was recognised, due to the constant opponent and time pressures that are placed upon performers. He aimed to compare the efficiency of pass in elite versus non-elite Turkish performers. All passes were recorded as either positive or negative, according to their perceived degree of difficulty and success. It was concluded, as expected that speed, fluency and intensity of pass are all more apparent for elite performers.
A further technical study on elite Turkish footballers was reported by Eniseler et al., (1996). The researchers found that Galatasary’s failure in European football competition was due to technical and tactical inadequacies as well as a lack of physical conditioning. This method of performance profiling also included recording variables as either positive or negative, according to their execution.
A tactical and technical inadequacy leading to failure was also reported by Acar (1996) who analysed the performance of teams playing in derby matches, using both computer and hand notation.
The stated research has all described the relative success of play in relation to entire team performances. A team is defined as a system in that a group of players interact in a dynamic fashion concerning a single purpose (Pinto, 1998). Despite a team participating as a homogenous unit, it is also vital to remember that the different individuals comprising a single team make it heterogeneous at the same time (Pinto, 1998).
2.3 Evaluation of Individuals Performance
Success in football is very much judged on a team’s ability to win matches (Luhtanen et al., 2001). The study of individual’s performance can be regarded as invaluable as it is in essence these individuals which comprise any team. Success at any level collectively cannot be achieved without the performance of individuals within this team unit.
A great deal of individual analysis has been conducted on the physical demands of football competition and the necessary physiological state for optimum performance (Reilly and Thomas, 1976; Bangsbo, 1997; O’Donoghue et al., 2001). Wells and Reilly (2002) attempted to research into the demands of playing position within women’s soccer also taking into account performance variables. However the only performance variable measured was kicking distance. This variable seems very irrelevant to determining successful performance within a game situation, particularly within elite level International football.
The lack of literature relating to the importance of individuals levels of skill was identified by Reilly and Holmes (1983). Reilly applied 2 methods in order to investigate the notion of skill distribution within soccer. Match analysis of 6 non professional games was carried out looking at skill performances as either successful or unsuccessful. In addition to this analysis, a group of 40 adolescent males, from a variety of outfield positions performed a cross section of skills tests. From the 2 tests, Reilly concluded that significantly:
i. Success rate of each skill depends upon pitch location
ii. Defensive area provides highest skill success rate
iii. Midfield players show more superior test scores to defenders
Reilly explained that as the space available from the opponent’s goal increases, the time available on the ball also increases. This explains why the most successful skills are performed in the defensive area, where less pressure is applied. It was also suggested that a common trend is to place the most poorly equipped players in defensive roles, hence the defenders performing worst on the skills test.
James at al., (2002) recognised the importance of studying individuals within a team. He stated that this level of deeper analysis allows a much finer grained overall team examination. In a study of the same team over 21 matches, across various competition types, the analysis aimed to identify the different roles individuals may take across differing circumstances. It was noted that in European competition players played more defensively and played passes involving much less risk.
Dufour (1993) completed a technical analysis of outfield players, summarising the percentage of time spent in each action category. For an outfield player it was reported that on the ball playing time was divided into:
50.6% Intercepting, 22.4% Passing, 18.7% Controlling ball, 4.5% Tackling, 2.4% Shooting and 1.4% other activities. Although this analysis enabled a template of the aspects contributing to an outfield player’s role, no specification was made relating to playing position, taking into account the obvious differences which occur between the outfield positions.
The lack of individual analysis relating to the highly specialised position of a goalkeeper was identified by Wooster and Hughes (2001). Goalkeepers were seen as vitally important, as they provide the last line of defence and the first line of attack for any team. From studying 1126 goalkeeper distributions at Euro 2000 with a hand notation system, it was concluded that successful goalkeepers used an equal distribution of kicks and throws, with variety which enabled possession to be maintained in the attacking third of the field. 24% of the 67 goals scored within the tournament all originated from successful goalkeeper distribution.
Researchers have also used other methods, other than standardised hand and computer notation systems in order to investigate the performance of individuals.
A qualitative analysis of individual movement patterns was performed by Grehaigne et al., (2001). A player’s effective play space was considered by drawing polygonal lines to create an individuals players action zone. This action zone represented the areas in which 80% of the players activities were performed.
Graphic modelling and statistical calculations were used by Chernenjakov and Dimitrov (1988) to help detail individual players performances. By entering specific data into a computer, it allowed players to be arranged in order of their playing effectiveness.
Erdmann (1993) described how due to the imprecise, subjective and ambiguous nature of qualitative observations, all quantitative analysis should be performed based upon mechanical properties. Erdmann introduced how by looking at the Kinematics of movement, such as the displacement, velocity and acceleration of movements, individual performance profiles could be built.
2.4 Use of Match Analysis by Coaches
As stated by Coghlan (1990) there is enormous pressure on football mangers throughout the world to succeed. In an attempt to bring about such success, notational analysis is being increasingly used within the modern game (Partridge and Franks, 1997). It can help to provide coaches with detailed analysis of observations that would otherwise be missed (Coghlan, 1990). Many coaches now consider information derived from such technological advances to be invaluable (Liebermann et al., 2002). With the pace of the modern day game, team strategies and tactics should be based on something more substantial than opinion (Bate, 1988).
Match analysis enables accurate, objective and relevant feedback to be applied to a coach or a performer about past performances (Franks and McGarry, 1996). Due to coaches being active, biased observers of their team’s performances, their observations are often not accurate. In a study by Franks and Miller (1986), International level coaches were only able to recollect 30% of the key elements which determined performance with the use of their memory alone (cited in Franks and McGarry, 1996).
The presentation of accurate results takes away any subjective views and opinions and allows a coach to build up a portfolio of all future opponents in order to prepare to play against them (Pollard et al., 1988).
Olsen and Larsen (1997) showed how the outcome of analysis can be a tool for evaluation and for the development of team tactics. The system responsible for such analysis must however be valid, accurate and easy to use, without large tables of complicated figures and graphs (Gerisch and Reichelt, 1993). Such simple but detailed analysis systems have enabled Norway to maximise its limited resources and to compete on the International football arena (p.220).
Franks and Goodman (1986) stated that an objective quantification of critical events during a game is critical for a complete post match analysis. The generated analysis must be used by coaches to instigate an observable change in behaviour, and so an improvement in performance. Liebermann et al., (2002) and Franks and McGarry (1996) reinforced this notion by stating that appropriately timed feedback can significantly improve motor skill acquisition and performance.
Reporting to the results of both qualitative and quantitative feedback to a performer can increase performance (Partridge and Franks, 1997). Following matches, a subject was shown analysis results, and video clips from relevant expert performances which related to his previous performance. Over the course of 6 games, the subject’s performance across 15 measured variables did improve. This performance increase was directly related to the analysis procedures the player was subjected to between performances.
2.5 Individual Roles Within a Team Framework
Although a team unit is comprised of 11 individuals, all 11 players must assume certain roles and functions in order to make such a team unit a success.
Subconsciously, players and coaches alike have a universal knowledge of which technical components are required in order to play in each position within association football. There is however very little research to either reinforce or question these concepts. Having an exact technical analysis of the precise playing requirements of each position would allow accurate training schedules and more accurate player profiles to be established.
Many coaching publications state the necessary credentials to play in certain positions within soccer (Smith, 1973; Cook, 1982). These publications are however based upon opinion, as opposed to exact epidemiological research. Much ambiguity does exist between these opinions and the reported differences. Wiemeyer (2003) in interviewing 14 coaches, across varying participation levels in order to establish positional technical demands emphases this. In only one case did all coaches agree of the exact functions of a position.