Ethical considerations The Ethics Committee of the University of Gothenburg approved the study: PHYSBI intervention study: EPN Göteborg Dnr: 300-16. The control group will have a physiotherapy session once and will be given general advice about physical activity. There will be a possibility to individualize treatments i.e. the same intensity but different exercises to better fit the needs and preferences of different individuals. Coding and anonymization of data occur after data collection is complete.