The German Register for Deaths in Sports.

Thomas Müller is a German professional footballer who plays for Bundesliga club Bayern Munich and the German national team shared this message on Twitter:

"Today I want to address all athletes with this video to draw attention to a topic that nobody wants to come into contact with, but which is of great importance for medical research in this field: The German Register for Deaths in Sports."

https://twitter.com/esmuellert_/status/1488123455652478979