1. Section of Sport Science; Department of Public Health; Aarhus University; Aarhus Denmark
2. The Medical Research Laboratory; Department of Clinical Medicine; Aarhus University; Aarhus Denmark
3. Institute of Regional Health Research; University of Southern Denmark; Odense Denmark
4. The Multiple Sclerosis Clinic of Southern Jutland (Sønderborg, Vejle, Esbjerg); Department of Neurology; Sygehus Sønderjylland; Sønderborg Denmark
5. The Multiple Sclerosis Clinic; Department of Neurology; Aarhus University Hospital; Aarhus Denmark