1. Department of Respiratory Diseases, Aalborg University Hospital, Aalborg, Denmark
2. The Clinical Institute, Aalborg University, Aalborg, Denmark
3. Section of Sport Science, Department of Public Health, Aarhus University, Aarhus, Denmark
4. Department of Respiratory Diseases, Sygehus Lillebaelt, Vejle, Denmark
5. Department of Regional Health Research, University of Southern, Denmark