Funding for this research was provided by:
Received: 25 May 2020
Accepted: 12 January 2021
First Online: 6 February 2021
Compliance with ethical standards
: All authors declare that they have no conflict of interest.
: All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards. The study was approved by the ethics committee of the German Sport University Cologne.
: Informed consent was obtained from all individual participants included in the study.