2. MOVEMENT ANALYSIS

O-007 Deceleration movements performed during FA Premier League soccer matches

Jonathan Bloomfield¹, Remco Polman² and Peter O'Donoghue^3
1Sports Institute Northern Ireland, University of Ulster, Jordanstown, County Antrim, BT37 0QB, UK
²Department of Sport Science, the University of Hull, Cottingham Road, Hull, East Riding of Yorkshire, UK
³School of Sport, University of Wales Institute Cardiff, Cardiff, CF23 6XD, UK

OBJECTIVE Deceleration (DCL) of high intensity movements in soccer has been related to cause of muscle damage (Reilly, 1990), which may be related to injury. Time-motion analysis can identify a breakdown of match time between different locomotive movements (LM). However, previous studies have not included deceleration as a movement classification and as a result such information has not been reported. The purpose of the current investigation was to characterise the nature of DCLs performed during elite soccer competition.

METHODS The on-field activity of 55 FA Premier League soccer players was recorded from Sky Television's PlayerCam facility for approximately 15 minutes each. The purposeful movement within these observations (about 5 minutes per player) was analysed using the Bloomfield Movement Classification (Bloomfield et al., 2004) allowing LM, direction and intensity of movement to be recorded.

RESULTS A total of 26,613 movements were recorded and 514 of these were DCL events. The analysis indicates that a player will perform a mean of 9.3 DCLs per 15mins. Table 1 shows the LM performed immediately before and after each DCL. There were 76.9% of the DCLs performed after sprinting and 41.6% of activity performed after all DCLs were classed as high intensity.

Table 1. Frequency of locomotive movements performed immediately before and after decelerations during 13 hours and 45 minutes of soccer match play.

DISCUSSION The mean duration of all DCLs was 0.82s, however, there were 72.2% of all DCLs less than 1s and 95.5% less than 2s. The current results provide useful knowledge for strength and conditioning and injury prevention and rehabilitation exercises specifically for elite soccer players.

REFERENCES
Bloomfield et al. (2004) Int J PerformAnalysis Sport 4, 20-31.
Reilly (1990) Football. In: Physiology of Sports. Eds: Reilly, T. et al.). London: Chapman & Hall. 371-424.

KEY WORDS Deceleration, injury prevention, strength, conditioning

O-008 A technical analysis of elite male soccer players by position and success

Mike Hughes and Craig Maloney
Cpa, Uwic, Cyncoed, Cardiff Cf23 6xd, 2Cpa, Uwic, Cyncoed, Cardiff Cf23 6xd, UK

OBJECTIVE If an analysis of the technical attributes of each player position was defined, results would influence selections and coaching. Notational analysis literature has few examples of technical analysis, in particular skill analysis involving soccer. This study developed analysis systems concerned with the technical requirements of each position in soccer, by using qualitative data within a quantitative system. The aim of this study was to analyse the technical ability of every individual that competed in the 2004 European Football Championships. The measurements were based on a subjectively drawn continuum that analyses a player's technical execution of actions in the game. It was investigated whether technical differences occurred between player positions and successful and unsuccessful teams.

METHODS Data were gathered from matches within the 2004 European Championships (n = 31). A specifically designed notation system was tested for reliability by % error and the Chi-Squared test of independence. P value of 0.99 indicated strong inter-observer reliability between action observations, and 5.32% error was accepted as being acceptable given the subjective and qualitative nature of the data.

RESULTS The technically best team did not win the tournament; Greece was joint 10th in the overall technique-ranking table. Portugal and the Czech Republic had the highest average technique scores. The successful teams during the early rounds had higher technique scores in all positions but in the semi finals and finals the losing teams had the higher technique scores (Table 1).

Table 1. Technical Score summations for selected team's skill rating.

DISCUSSION A regression was made between the team's final position and their technique ratings at different skills. It gave insight into the relative strengths and weaknesses of these Performance Indicators. 'Heading' and 'running-with-ball' were ranked at the top, whilst fine skills, 'passing' and 'dribbling', were rated at the lowest. Perhaps this reflected the surprise result of the tournament.

KEY WORDS Technical analysis, elite male soccer, player position, success.

O-009 Method comparison of linear distance and velocity measurements with global positioning satellite (GPS) and the timing gate techniques.

Matthew Portas¹, Chris Rush¹, Chris Barnes² and Alan Batterham^1
1University of Teesside, UK, ²Middlesbrough Football Club, UK

OBJECTIVE Objective quantification of training volume and intensity in football has proved a complex task. Timing gates permit the quantification of speed over pre-planned distances but are not suitable for general training drills, which are random and multidirectional. Recent developments in GPS technology offer potential to overcome logistical issues and restrictions of the timing gate method. Currently, there is a limited understanding of the measurement properties of commercially available GPS units in football training environments. Therefore, the aim of this investigation was to perform a method comparison of linear distance and velocity measurements with commercially available GPS units and the timing gate technique.

METHODS Three Doppler shift 1 Hz GPS units were used to estimate distance (m) and velocity (km/h) in a linear running protocol at varying velocities and were compared against timing gates over 10 trials. For GPS-estimated distance, mean % error was calculated. For velocity a log-transformed linear regression was conducted. The standard error of the estimate for each unit was expressed as % CV.

RESULTS The error for GPS distance measurements varied by the velocity of the trial. The mean % error was highest during running at 22.5km/h (5.64%; 2.82m). The lowest % error (0.71%; 0.36m) was at the slowest velocity of 6.45 km/h. At the highest velocity (27 km/h) the mean % error was -1.51% (-0.76m). The % CV for the GPS-estimated velocity was 1% for each of the three units (95% CI 0.8% to 1.2%).

DISCUSSION GPS and timing gates produced comparable speed and distance data. One Hz seems appropriate for predicting distance at low velocity, but may be insufficient for higher velocity. Some error reported may be due to timing gate measurement issues and not the GPS technology. Doppler shift appears to improve the variability of the GPS speed data.

CONCLUSION To quantify football related movements' future work should consider comparison of GPS and image-based video analysis technology on non-linear courses.

KEY WORDS Technology, displacement, speed.

O-010 Analysis of technical-tactical parameters in young soccer players

Juan Merce¹, Ramon Garcia¹, Alberto Pardo², Jose Enrique Gallach¹, Jose Javier Mundina¹ and Luis-Millan González^1
1Universidad de Valencia, Valencia, Spain, ²Universidad Catolica de Valencia, Valencia, Spain

OBJECTIVE A soccer player's achievement depends on variables such as psychology, physical condition, coordination and cognition. Although researchers have focused on all variables, investigation in how the tactic influences achievement is yet unknown (McMorris, 1997; Rulence-Pâques et al, 2005). No experimental evidence exists about relation between technical and tactical actions. The principal aim of the study was to analyze the technical and tactical actions of passing, looking and opening space, and shooting the ball towards a goal in a football match.

METHODS Four groups of twelve football players participated in this study. They belonged to two age categories (8-12 years). Three technical-tactical tests were used to measure the variables (passes, looking opening space and shoots to the goal). In order to carry out the subsequent analysis, two video cameras (Panasonic AG-DVX 100AE) were used for filming.

RESULTS The descriptions of all the measured variables are shown in Table 1. No significant differences were obtained in any of the variables analyzed in relation to category, position and/or dominance of subjects. A positive correlation was found between the number of correct, looking opening space, and the number of goals scored (r = 0.765, p < 0.001. n = 48).

Table 1. Descriptions of the variables measured

DISCUSSION The present study showed no significant difference among the means of independent variables analyzed. Nonetheless, significant relations were found among the technical and tactical variables studied. It would be interesting to prolong observation times in future investigations to increase the likelihood of finding significant differences among the independent variables analyzed.

REFERENCES
McMorris (1997) Percept Mot Skills 85, 467-476.
Rulence-Pâques et al. (2005) Revue Eur Psych Apliquée 55, 131-136.

KEY WORDS Soccer, technique, tactic.

O-011 Automatic analysis of football games using GPS on real time

José Pino¹, Raul Martinez-Santos³, Maria Isabel Moreno² and Carlos Padilla^2
1University of Extremadura, ²Manager of C&M, ³University of the Basque Country

OBJECTIVE Global Positioning System (GPS) is a localization system designed by the United States Department of Defence in 1978 that allows knowing latitude, longitude and altitude. To a certain extent, soccer action implies using space in an intelligent way that can be tracked by describing players' positions on the pitch. This technology has been used in human movement studies as well for the study of human locomotion and cross-country skiing for instance. The main objective of this investigation was to test and ad hoc designed and developed application for real time recording of cinematic and physiological variables of team sports.

METHODS The participants were 6 professional football players of 2nd B division El Ejido FC who played a 60'game (30'+30') practice game. Each of the participants wore a FRWD F 500 GPS set consisting of a recording unit, a tape and a heart rate (HR) transmitter band. All data produced during play action (velocity, distance, HR and position) were taken every second and stored constantly on the recording unit.

RESULTS According to collected data we found significant differences in distance travelled in four of the six players whereas HR was different for all players monitored. As far as velocity was concerned, differences were only found for three participants (Table 1).

Table 1. Inter-subject analysis of the variables (Heart Rate, Speed and Distance p < 0.005).
Right defender Mid-R defender Left defender