1. REVAL Rehabilitation Research Centre, Biomedical Research Institute, Faculty of Medicine and Life Sciences, Hasselt University, Diepenbeek, Belgium
2. Section of Sport Science, Department of Public Health, Aarhus University, Aarhus, Denmark
3. Institute of Regional Health Research, University of Southern Denmark, Odense, Denmark / Department of Neurology, MS-Clinic of Southern Jutland (Sønderborg, Esbjerg, Vejle), Sønderborg Hospital, Denmark