Modelling movement energetics using Global Positioning System (GPS) devices in contact team sports: limitations and solutions

Quantifying the training and competition loads of players in contact team sports can be performed in a variety of ways, including: kinematic, perceptual, heart rate or biochemical monitoring methods. Whilst these approaches provide data that are relevant for team sports practitioners and athletes, their application to a contact team sport setting can sometimes be challenging or illogical. Furthermore, these methods can generate large fragmented datasets, do not provide a single global measure of training load and cannot adequately quantify all key elements of performance in contact team sports. A previous attempt to address these limitations via the estimation of metabolic energy demand (global energy measurement) has been criticised for its inability to fully quantify the energetic costs of team sports, particularly during collisions. This is despite the seemingly unintentional misapplication of the models’ principles to settings outside of its intended use. There are other hindrances to the application of such models, which are discussed herein, such as the data-handling procedures of global position system manufacturers and the unrealistic expectations of end-users. Nevertheless, we propose an alternative energetic approach, based on GPS-derived data, to improve the assessment of mechanical load in contact team sports. A framework for the estimation of mechanical work done during locomotor and contact events with capacity to globally quantify the work done during training and matches is presented.