The accurate measurement of ground reaction forces (GRFs) is confined to laboratory-based settings. This poses an ongoing problem for sports biomechanists working in the field given the necessity of this variable for input into the commonly employed inverse dynamics modelling approach. In addition, GRFs are also used by the wider sport science community for assessing player “workload” metrics. Non-invasive in-field estimation of GRFs could facilitate the development of an in-field tool which has the potential to revolutionise the side-line management of players from a number of perspectives. The aim of this study was to use a least squares estimator (LSE) matrix to estimate GRFs from 2D video with r\u3e0.8 results found for the vertical and horizontal GRF components. These results provide early support for the efficacy of non-invasive estimation of GRFs in the field determined from 2D video footage in isolation
