Howe, Samuel ORCID: 0000-0003-2325-3994 (2020) Quantifying & Characterising Peak Intensities of Professional Rugby using GPS & Accelerometers. PhD thesis, Victoria University.

Abstract

The use of wearable technology in team sports to quantify physical activity during training and competition is now ubiquitous. Coaches typically use information derived from player tracking technologies such as Global Positioning Systems (GPS) to prescribe and monitor training. If coaches prepare players relative to the average intensity of competition, they will be underprepared for the rigors of competiton. Despite the majority of team sport competition being spent at submaximal intensity, high-intensity activities are often aligned with key events that determine match outcome. Therefore, coaches should periodically expose players to the physical worst-case scenarios of competition, whilst concurrently training tactical and technical qualities so that players may thrive and not simply survive during these intense periods of match-play. Understanding the utility of player tracking technologies, measures and analysis techniques for identifying and quantifying peak periods of competition enables coaches to more accurately interpret and use the data to inform match-specific training practices. This series of studies sought to identify, quantify and characterise the most intense periods of professional rugby competitions and periods thereafter with the aim of helping coaches to prescribe and monitor training that is more representative of competition and aid match-day tactical decisions. Despite tri-axial accelerometers being embedded within GPS devices, their use for quantifying intense periods of team sport movement in research and practice is limited. Study one (Chapter 3) found that accelerometers outperformed GPS in quantifying positional and match-half peak intensity differences during rugby competition, identified using rolling epoch analysis. Accelerometers provided meaningful additional information to GPS technology that may aid practitioners in physically preparing and monitoring rugby players. Study two (Chapter 4) assessed the sensitivity, reliability and convergent validity of GPS and accelerometer measures for quantifying peak intensities of rugby. The poor sensitivity and low reliability of GPS and accelerometer measures implied that rugby players need to be monitored across many matches to obtain adequate precision for assessing individuals. Study three (Chapter 5) examined factors that may influence peak intensities of rugby competition, such as exercise duration, positional group, match-half, level of competition, within-season trends and time spent on field. Findings provide professional rugby coaches with duration- and position-specific intensities to aid prescription and monitoring of match-specific training, whilst improving broader understanding of factors that influence player movement intensity. Study four (Chapter 6) sequentially tracked the time-course of exercise intensity declines post the most intense periods of rugby competition using novel analysis. Exercise intensity declined sharply post the most intense periods of competition, falling below the match average intensity and rarely returning shortly thereafter. Findings may inform tactical match decisions and match representative training prescription and monitoring. Finally, study five (Chapter 7) established that professional rugby peak intensities of competition can be accurately predicted from exercise duration using power law statistical modelling, irrespective of playing position, match-half, level of competition or measure of exercise intensity. Novel insights on model prediction error as well as the patterns of error as a function of time may assist coaches to accurately interpret and use power law to prescribe and monitor match-specific training.

Search Google Scholar

Repository staff login