Mr. Olympia contestant George Peterson was found deceased in his hotel room on Wednesday in Orlando, Florida.
Peterson, 37, was just days away from competing in the 2021 Mr. Olympia finals in Orlando when he died.
His body was found by retired American bodybuilder Dave Palumbo who told RxMuscle that Peterson was face down in hotel room.
Palumbo went to check on Peterson when his coach could not reach him by phone.
RxMuscle claims there was blood around Peterson's nose - which Palumbo suggested could be from a ruptured brain aneurysm.
Peterson was fully vaccinated as required to participate in the Olympia finals.
There have been multiple instances of brain aneurysms and blood clots reported in people who received the Covid-19 mRNA vaccines.
Mr Olympia's Instagram page announced Peterson's death:
"It is with great sadness that we report the unexpected passing of George Peterson, a champion on stage and off.
"Our condolences go out to his family and all who respected and admired one of the kindest men we have ever known."