Niehues, Maike http://orcid.org/0000-0002-7233-4486
Gerlach, Erin http://orcid.org/0000-0003-4277-3303
Sallen, Jeffrey http://orcid.org/0000-0002-9042-9104
Funding for this research was provided by:
Ministerium für Bildung, Jugend und Sport des Landes Brandenburg
Bundesinstitut für Sportwissenschaft (071102/16-21)
Universität Potsdam
Article History
Received: 9 February 2021
Accepted: 4 May 2021
First Online: 18 June 2021
Declarations
:
: M. Niehues, E. Gerlach and J. Sallen declare that they have no competing interests.
: The study was approved by the local school ministries and the ethics committee of the University of Potsdam (Germany). All research procedures were in line with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.