1. Institute of Clinical Exercise and Health Science, University of the West of Scotland, Hamilton, Lanarkshire, UK
2. The Physical Activity Exchange, Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK
3. Cardiff School of Sport, Cardiff Metropolitan University, Cyncoed Campus, Cardiff UK
4. Department of Human Biology, University of Cape Town and Sports Science Institute of South Africa, Newlands 7700, South Africa
5. School of Clinical Sciences, University of Bristol and Bristol Royal Hospital for Children, Bristol, UK