Centre of Precision Rehabilitation for Spinal Pain (CPR Spine), School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, UK. Department of Integrative Physiology, University of Colorado Boulder, CO, USA. Faculty of Electrical Engineering and Computer Science, University of Maribor, Koroška cesta 46, Maribor, Slovenia. US Department of Veterans Affairs, USA. Department of Bioengineering, Imperial College London, London, UK. School of Health and Rehabilitation Sciences, The University of Queensland, Brisbane, Australia; School of Biomedical Sciences, The University of Queensland, Brisbane, Australia. School of Biomedical Sciences, The University of Queensland, Brisbane, Australia; LAMHESS, Université Côte d'Azur, Nice, France; Institut Universitaire de France (IUF), Paris, France. Trinity College Institute of Neuroscience and School of Psychology, Trinity College Dublin, Dublin, Ireland; School of Psychology, Queen's University Belfast, Belfast, UK; School of Human Movement and Nutrition Sciences, The University of Queensland, Brisbane, Australia. Worcester Polytechnic Institute, Worcester, MA, USA. Department of Rehabilitation and Prevention Engineering, Institute of Applied Medical Engineering, RWTH Aachen University, Aachen, Germany. Department of Human Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam, the Netherlands. Neuroscience Research Australia, University of New South Wales, Sydney, Australia. School of Electrical and Electronic Engineering, University College Dublin, Belfield, Dublin, Ireland. Department of Clinical Research and Department of Sports Sciences and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark. Auckland Bioengineering Institute and Department of Engineering Science, University of Auckland, Auckland, New Zealand. LISiN, Department of Electronics and Telecommunications, Politecnico di Torino, Torino, Italy. Brain and Mind Centre, University of Sydney, Sydney, Australia Department of Neurology, Royal Prince Alfred Hospital, Sydney, Australia. Sobell Department of Motor Neuroscience and Movement Disorders, UCL Institute of Neurology, London, UK. Northwestern University, Evanston, IL, USA; Shirley Ryan AbilityLab, Chicago, IL, USA. School of Health and Rehabilitation Sciences, The University of Queensland, Brisbane, Australia. Electronic address: p.hodges@uq.edu.au.