Variables Governing the Dynamics of Attacker-Defender Systems in Team Sport Brooke Kennedy A thesis submitted for the degree of Masters in Applied Science at the Queensland University of Technology and the Centre of Excellence for Applied Sports Science Research Queensland Academy of Sport Australia 2010 2 Keywords Action, affordance, attunement, complex system, control parameter, constraints, decision making, ecological dynamics, interpersonal distance, netball, order parameter, perception, relative velocity, team sport. 3 List of Figures Figure 1 A model depicting how organismic, task and environmental constraints interact to channel behaviour 19 Figure 2 Set up of Netball Playing Positions – The Netball Court 39 Figure 3 Conceptual hierarchical framework for the perception, action and decision making processes of athletes 46 Figure 4 Factors critical to the perception, decision making and action of netball athletes from a constraints-led approach 48 Figure 5 The manifestation of Interpersonal Distance between a) an attacker and defender; and b) the attacker and the ball, and the defender and the ball 56 Figure 6 The capture of player motions during the centre pass. Single digital video camera mounted above the playing court 78 Figure 7 Reference points for digitised runs 90 Figure 8 Interpersonal Distance (IPD) and Relative Distance to the Ball (RDB) 92 Figure 9 Example of the effect of relative distance to the ball (RDB) – trial 1 94 Figure 10 Example of the effect of relative distance to the ball (RDB) – trial 2 94 Figure 11 Example of the effect of relative distance to the ball (RDB) – trail 3 95 Figure 12 Example of the effect of relative distance to the ball (RDB) – trail 4 95 Figure 13 Example of the effect of interpersonal distance – successful trial 97 Figure 14 Example of the effect of interpersonal distance – unsuccessful trial 97 4 Figure 15 The effect of interpersonal distance on the stability of 1v1 netball dyads 98 Figure 16 The nested effect of interpersonal distance and relative distance to the ball 99 Figure 17 Three phases of netball system stability 100 Figure 18 The Collective structure 102 Figure 19a) Relative velocity between attacker and defender – successful trial 1 104 Figure 19b) Relative velocity between attacker and defender – successful trial 2 104 Figure 20a) Relative velocity between attacker and defender – unsuccessful trial 1 104 Figure 20b) Relative velocity between attacker and defender – unsuccessful trial 2 105 5 List of Tables Table 1 Candidate Control Parameters Identified Through Experiential Knowledge of High Performance Coaches in Netball 54 Table 2 Classification of Attacking System Stability Relative to System Parameters 109 6 Table of Contents Chapter 1 9 1.1 General Introduction 10 1.2 Decision Making in Team Sport 13 1.2.1 Limitations of Traditional Methodologies of Human Behaviour 13 1.3 The Ecological Dynamics Approach 15 1.3.1 The Role of the Complex System 15 1.3.2 Team Sport as a Complex System 17 1.3.3 Self Organisation 19 1.3.4 Control Parameters Driving Phase Transitions in Complex Systems 20 1.3.5 Information: The Driving Force Behind Movement Coordination 21 1.4 The Role of Ecological Dynamics in the Study of Perception, Decision Making and Action in Team Sport 23 1.4.1 The Role of Qualitative Analysis and Experiential Knowledge 26 1.4.2 Netball as a Complex, Dynamical System 28 1.4.3 Netball as an Exemplary Vehicle for Studying Perception, Decision Making and Action in Team Ball Sports 30 1.4.4 Aims of the Current Thesis 32 Chapter 2 35 2.1 Abstract 36 2.2 Introduction 37 2.2.1 The Role of Control Parameters 37 2.3 Methods 41 2.3.1 Participants and Sampling Procedures 41 2.3.2 Procedures, Power and Precision 41 2.3.3 Task, Apparatus and Data Analysis 43 7 2.4 Results 46 2.4.1 Task, Environmental and Personal Constraints on Performance 46 2.4.2 Interpersonal Distance (IPD) 54 2.4.3 Relative Velocity 56 2.4.4 Ball Flight Time (BFT) and Ball Contact Time (BCT) 57 2.5 Discussion 61 2.5.1 The Role of Experiential Knowledge 62 2.5.2 The Role of Information: Affordances for Action 64 2.6 Conclusions 67 Interlude and Summary 69 Chapter 3 70 3.1 Abstract 71 3.2 Introduction 72 3.2.1 Self-Organisation 73 3.3 Methods 77 3.3.1 Participants and Sampling Procedures 77 3.3.2 Task and Apparatus 77 3.3.3 Procedure, Power and Precision 79 3.3.4 Data Analysis 81 3.3.5 Reliability and Validity of Fixed, Single Camera Methods for examining Pattern Forming Dynamics 82 3.3.6 Considerations in the use of Direct Linear Transformation (DLT) from fixed camera positions 83 3.3.7 2D versus 3D Approaches in Tracking Human Motion 85 3.3.8 Limitations and Recommendations 86 3.3.9 Validity and Reliability for Netball Sub-phases using TACTO 89 8 3.4 Results 91 3.4.1 Accuracy and Reliability 91 3.4.2 Interpersonal Distance (IPD) and Relative Distance to the Ball (RDB) 91 3.4.3 Nested Control Parameters 99 3.4.4 Collective Structures 101 3.4.5 Relative Velocity 103 3.5 Discussion 106 3.5.1 Interpersonal Distance (IPD) and Relative Distance to the Ball (RDB) 107 3.5.2 Affordances for Action 110 3.5.3 Perceptual Attunement 111 3.5.4 Relative Velocity 113 3.6 Conclusions 116 Chapter 4 118 4.1 Conclusions and Future Research Recommendations 119 4.2 References 124 4.3 Interview Transcripts 136 9 CHAPTER 1 Introduction Page Section 10 1.1 General Introduction 13 1.2 Decision Making in Team Sport 13 1.2.1 Limitations of Traditional Methodologies of Human Behaviour 15 1.3 The Ecological Dynamics Approach 15 1.3.1 The Role of the Complex System 17 1.3.2 Team Sport as a Complex System 19 1.3.3 Self Organisation 20 1.3.4 Control Parameters Driving Phase Transitions in Complex Systems 21 1.3.5 Information: The Driving Force Behind Movement Coordination 23 1.4 The Role of Ecological Dynamics in the Study of Perception, Action and Decision Making in Team Sport 26 1.4.1 The Role of Qualitative Analysis and Experiential Knowledge 28 1.4.2 Netball as a Complex, Dynamical System 30 1.4.3 Netball as an Exemplary Vehicle for Studying Perception, Decision Making and Action in Team ball Sports 32 1.4.4 Aims of the Current Thesis 10 1.1 General Introduction The purpose of this thesis is to identify and examine the role of key variables on the perception, decision making and actions of team sport athletes through theoretical insights provided by the ecological dynamics perspective. Sports fans all over the world are constantly in awe over the technical, tactical and physical skills exhibited by elite athletes. Sports scientists and coaches alike are continually trialling and researching new and improved methods with the common goal of identifying the reasons behind ultimate success and sporting prowess. In the realm of skill acquisition, researchers have come to the agreement that accurate perception, action and decision making are all characteristics of expert performance (Hodges, Starkes & MacMahon, 2006; Starkes & Erricsson, 2003). However, often referred to as “innate” talent or “natural” ability, training these characteristics to enable an athlete to cope with the demands of a dynamic team sport environment, often poses a challenge to coaches – how do you train natural phenomenon? Many would agree that the competitive environment of team sport provides a source of uncertainty and unpredictability for all players involved. With the interactions that emerge between team mates and their opponents during specific passages of play, it is never with 100% certainty that players know what their opposing competitors are going to do at every moment of the game (Passos, Araújo, Davids & Shuttleworth, 2008a). Why, therefore, do many traditional methods of training typically prepare athletes for the predictable moments in play and the resultant certainty of their actions? The following thesis will attempt to theoretically resolve this issue through conceptualising team sports as complex systems, open to the many information fluxes provided by the environment, and constantly changing and adapting its structural organisation through interactions of system components: the players. This conceptualisation will lead to 11 discussions on how to properly prepare players for the emergent interpersonal interactions that occur during a match, along with implications for training design and an understanding into the coupling of perceptual information with the actions and behaviours produced by a performer. The first chapter of the thesis will clarify the theoretical justifications and basis for the empirical studies reported in Chapters 2 and 3. Firstly, a brief overview will be provided on the limitations of traditional approaches to skill acquisition. Subsequently, an alternative framework in the form of Ecological Dynamics will be discussed, with the role of the complex system and the perception of information adapted to the realm of team sport. Next, an in-depth description will be provided on how the Ecological Dynamics approach provides researchers with an effective framework for the study of perception, decision making and action in sport, with the identification of specific sub-phases of play and key variables playing a significant role in the pattern-forming dynamics of team sport athletes. Specifically, the sport of netball will be used as a research vehicle exemplifying the dynamic, unpredictable and uncertain environment characteristic of team ball sports. As mentioned previously, chapters 2 and 3 will pose important empirical research questions with the ensuing investigations into the coordination of movement in emergent performance environments. In chapter 2, the role of experiential knowledge in the identification of key control parameters for performance will be addressed.