1 Norwich Medical School, University of East Anglia, Norwich, NR4 7TJ, UK. Electronic address: k.milton@uea.ac.uk.
2 School of Human Movement and Nutrition Sciences and School of Health and Rehabilitation Sciences, University of Queensland, Brisbane, QLD 4072, Australia.
3 Department of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense 5230, Denmark.