1 Department of Physiotherapy, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa. carel.viljoen@up.ac.za.
2 Sport, Exercise Medicine and Lifestyle Institute (SEMLI), Hillcrest Campus, University of Pretoria, Burnett Street, Hatfield, Pretoria, 0002, South Africa. carel.viljoen@up.ac.za.
3 Amsterdam Collaboration for Health and Safety in Sports, Department of Public and Occupational Health, Amsterdam Movement Sciences, Amsterdam University Medical Centers, Location VU University Medical Center, Amsterdam, The Netherlands. carel.viljoen@up.ac.za.
4 Sport, Exercise Medicine and Lifestyle Institute (SEMLI), Hillcrest Campus, University of Pretoria, Burnett Street, Hatfield, Pretoria, 0002, South Africa.
5 Section Sports Medicine, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa.
6 Amsterdam Collaboration for Health and Safety in Sports, Department of Public and Occupational Health, Amsterdam Movement Sciences, Amsterdam University Medical Centers, Location VU University Medical Center, Amsterdam, The Netherlands.
7 School of Human Movement and Nutrition Sciences, Faculty of Health and Behavioural Sciences, University of Queensland, Brisbane, Australia.
8 Division of Exercise Science and Sports Medicine (ESSM), Department of Human Biology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa.
9 School of Public Health, Physiotherapy and Population Sciences, University College Dublin, Dublin, Ireland.
10 Portugal Football School, Portuguese Football Federation, Lisbon, Portugal.
11 Department of Library Services, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa.
12 Department of Physiotherapy, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa.