Funding for this research was provided by:
Kavli Research Centre for Geriatrics and Dementia, Haraldsplass Deaconess Hospital, Bergen, Norway
Received: 28 May 2018
Accepted: 6 November 2018
First Online: 17 November 2018
Ethics approval and consent to participate
: The Tromso Study was approved by the Norwegian Data Inspectorate and the Norwegian Directorate of Health. Both studies were approved by the Regional Committees for Medical and Health Research Ethics, and comply with the Declaration of Helsinki. There are no conflicting issues relating to journal policies.Informed written consent was obtained from all included athletes and the participants in the Tromso-6 study.
: Not applicable.
: The authors declare that they have no competing interest.
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