1. Umeå Center for Functional Brain Imaging (UFBI), Umeå University, S-901 87 Umeå, Sweden
2. Centre for Demographic and Ageing Research (CEDAR), Umeå University, S-901 87 Umeå, Sweden
3. Department of Radiation Sciences, Umeå University, S-901 87 Umeå, Sweden
4. Department of Integrative Medical Biology, Umeå University, S-901 87 Umeå, Sweden
5. Danish Research Centre for Magnetic Resonance (DRCMR), Centre for Functional and Diagnostic Imaging and Research, Copenhagen University Hospital Hvidovre, DK-2650 Hvidovre, Denmark
6. Institute of Sports Medicine Copenhagen (ISMC), Copenhagen University Hospital Bispebjerg, DK-2400 Copenhagen, Denmark