Time Motion Analysis. Sports Analysis LG B518. Aims and Objectives. Investigating why time motion analysis is important when analysing performance

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1 Time Motion Analysis Sports Analysis LG B518 Image by paddynapper Aims and Objectives Defining Time Motion Analysis Investigating why time motion analysis is important when analysing performance This lecture will include Critically analysing examples from literature. Investigating the accuracy of motion analysis systems in different sports. 1

2 What is Time Motion Analysis? Definition Time motion analysis can be defined as the progressive changes of position and speed over a period of time (Hamill and Knutzen, 1996). Blood lactate concentration Heart rate Oxygen uptake during match play Rate of perceived exertion In practical terms the movement of an athlete over a period of match play and the speeds that they travel at during the performance. Time motion analysis provides an objective yet non invasive method for quantifying work rate during field based sports and is the most effective method of assessing the physiological demands placed on players at an elite level. (Bangsbo, 1994). Other methods which exist with the aim of quantifying work rate have the disadvantage of being invasive and often impractical or inaccurate during competitive match play. Image by cambria Why is Time Motion Analysis Useful? Provides coaches and players alike with feedback on performance (Hughes, 1996). Provides information regarding an individual players performance throughout a game or training session (Hughes, 1996). Allows understanding of the physiological and activity demands. of sport energy expenditure (Hughes, 1996). Time Motion Analysis. Can aid coaches in team and tactical selections or styles of play utilised (Hughes, 1996). Can be used to monitor seasonal variations in player performances/work rate (Bompa, 1999). 2

3 Why is Accuracy Important? Accuracy Time motion analysis data that is collected must be as accurate and detailed as possible. This is because inaccurate, invalid or unreliable data may provide coaches and athletes with incorrect information regarding work rate, exercise intensity, distances travelled and movement patterns during performance. How can motion analysis data be used? By finding the total distance covered in a game the energy expenditure can be calculated (Reilly and Thomas,1979). Data can be used to give a true reflection on the physiological demands of the game. Allows work-rest ratios and physiological requirements of the sports to be analysed and used to develop training programmes (Vallis, 1998). Image by digiarne Methods of Time Motion Analysis? Pro Zone Global Positioning Systems (GPS) Time Motion Analysis. Trak Performance Video/Computer Software Hand Notational Methods 3

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5 PROPERTIES Show Button: Automatic Tracking Systems What systems are Available? With developments in technology a range of automatic tracking systems are available, however they are still expensive to purchase and maintain. Examples of these systems include; Pro Zone 1414 Venatrack A-Eye System The systems are commonly used within elite level sport due to the financial costs of the systems. Each system has detailed features and the opportunity for in depth analysis and feedback. The systems all use specifically placed cameras around the playing area to calculate via trigonometry the distance s and speeds athletes are travelling at. A-Eye Tracking Output 5

6 PROPERTIES Show Button: Issues with Other Systems Hand Notational/Video Analysis Time motion analysis performed via hand notational/video methods have the significant advantage of being cheap and very cost effective compared to other more expensive software. However the time consuming nature means that it can take up to 8 hours from trained analysts to analyse one 80minute game of rugby union for one specific player (Roberts et al. 2006). With this in mind the time to analyse more than one player could be significantly more and may have an impact on the timing of feedback to the players/team. In regards to accuracy it has been suggested that hand notational systems have a high degree of validity (approx 2% error) for calculating the total distance travelled by an athlete issues concerning time spent working in high intensity speed zones seem to evident with overestimations of high intensity work performed (Roberts et al. 2006). Trak Performance Output Computerised Systems Limited research exists in regards to manual computerised tracking systems such as Trak Performance. Roberts et al. (2006) did suggest that such systems greatly over estimate high intensity work due to the nature of the software, suggesting overestimating by 27.5% more that what was actually performed. 6

7 Issues with Clock Time and Match Time What is the Difference? Clock time refers to the time the ball is in play during the game, Match time on the other had is the total duration of the match/event including stopages and points where the ball is out of play. Sports such as Australian Rules Football and Rugby League are based around clock timings. These factors have not been discussed in a range of time motion analysis studies (King and O Donoghue, 2003 and Castagna et al. 2004) Influence of Match vs. Clock Time Doğramacı and Watsford (2008) investigated the influence of clock time and match time on time motion analysis data collected during futsal match play. When comparing the data collected during the game for clock time and game time there was greater was a 16% greater total overall distance covered, a 6.9% increase in the time spent in lowintensity activities, and a change in activity every 4.00 s vs s, respectively. There was little change in the high-intensity activities from clocktime to match-time comparison. The results of the study suggest that clock time only may misrepresent the movement patterns in a ability to 'read the play/situation' game situation so a standard method of analysis focusing acquired upon game knowledge time should be used. A range of published decision-making studies do not skills indicate which method they utilised within the analysis process, this could be seen as a limitation of the studies. Image by luizfilepe How Can Time Motion Analysis Data Be Used? Development of Sport Specific Protocols Time motion analysis data allows coaches to develop fitness testing protocols which mirror the actual and specific demands of the sports match play. This is beneficial as results collected in such tests have a direct reflection on match play performance. A range of tests have been developed including; The Loughborough Intermittent Shuttle Test (LIST) for football The Netball Specific Fitness Test (NSFT) The Yo-Yo Intermittent Recovery Test The Badminton Specific Fitness Test (BSFT) The specific fitness tests are beneficial as they mirror the demands of match play and have greater worth in regards to athlete monitoring and fitness testing than the multi stage fitness test. Image by wonker 7

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9 References Bangsbo, J. (1994)The Physiology of Soccer With Special Reference to Intense Intermittent exercise. Bagsveard: HO+Storm. Barris, S. (2008) Automatic Tracking and the Analysis of Human Movement. Unpublished Phd thesis School of Physical Education, Dunedin, University of Otago. Bompa, T.O. (1999) Periodisation: Theory and Methodology of Training. Leeds: Human Kinetics. Castagna, C. Abt, G. and D'Ottavio, S. (2004) Activity profile of international-level soccer referees during competitive matches. Journal of Strength and Conditioning Research, 18, pp Coutts, A.J. and Duffield, R. (2010) Validity and reliability of GPS units for measuring movement demands of team sports. Journal of Science and Medicine in Sport. 13, pp Doğramacı, S.N. and Watsford, M.L. (2008) A comparison of two different methods for time-motion analysis in team sports. International Journal of Performance Analysis in Sport, 6 (1), pp Hamill, J. and Knutzen, K.M. (1996). Biomechanical Basis of Human Movement. USA: Lippincott Williams & Wilkins. Hughes, M. (1996) Notational analysis, in Reilly, T (ed.)science and Soccer. London: E&FN Spon, pp King, S. and O'Donoghue, P. (2003) The activity profile of men's Gaelic football. International Journal of Performance Analysis in Sport, 3, pp Petersen, C. Pyne, D. Portus, M. and Dawson, B. (2009) Validity and reliability of GPS units to monitor cricket specific movement patterns. International Journal of Sports Physiology and Performance, 4, pp Reilly, T. and Thomas, V. (1976) Motion analysis of work rate in different positional roles in professional football match play. Journal of Human Movement Studies, 2, pp References Roberts,S. Trewartha, G. and Stokes, K. (2006) A comparison of time-motion analysis methods for field-based sports. International Journal of Sports Physiology and Performance, 1, pp Vallis, A. (1998). Tracking a footballers movements and skills. Video Education Australia, 1, Videocassette 1. Williams, M. and Morgan, S. (2009) Horizontal positioning error derived from stationary GPS units: A function of time and proximity to building infrastructure International Journal of Performance Analysis in Sport, 9, pp