Fitness & athleticism are a careful balance. As with many things, too much is toxic. In the case of athletes - even amateurs - it's cortisol. I believe that some people are genetically predisposed to conditions which make heavy exercise absolutely deadly.
But because of the bias in medical research there's little money for hard science, rather steering researchers in directions which support orthodoxy. It's shameful.
That stated, it's impossible to speculate whether the jab was a factor at all...
...but we should all be free to ask questions (as opposed to those who wish to shut down all debate and all questions). I believe that cause of death is a public health issue, should always be determined without prejudice and be publicly available.
Ridiculous.
The number of healthy young athletes keeling over went up an order of magnitude as soon as they started getting jabbed and boosted. Just as many censored doctors and researchers had predicted would happen to the population.
It is not only possible, but also vital, that we speculate, test, and act on it.