The core focus of this thesis has been based upon the question of: Can accelerometers be applied to monitoring elite athletes as a novel system for the assessment of over- ground running speeds? At the onset of this research it was known that Global Positioning Systems (GPS) were the fundamental standard for monitoring speeds of athlete during field sports however their limitations and accuracies restrict their range of applications. This research therefore has been prefixed with an investigation into what current GPS systems deliver, and if there are any avenues in which GPS information can be improved upon. The thesis has therefore split into the following two focus areas: • 1) The development of a novel longitudinal data analysis application for GPS recordings from elite level competition and training; and • 2) The development of a new and alternative, independent system for tracking athlete over-ground running during competition from accelerometers. The first focus of this thesis involves the design and application of a GPS data system for investigating longitudinal athlete workloads and performance parameters. This system brought together a wide range of past research identified in the literature with new, desired workload and performance parameters identified by coaches, athletes and sports scientists. The application was shown to be a novel and effective method for comparing longitudinal GPS recordings through the comparison of the workload factors with recent findings from the literature. This system was shown to provide useful information as an add-on to current commercial systems.