Exercise tends to be pretty self-limiting.

Depends on the activity level and all that, but in general, even a few hours a few days a week is the most a person's likely to do.

And I know some ... reasonably well balanced people who do markedly more than that.

One thing about dying during exercise: you're going out doing something you enjoy. And which I suspect puts you in a good place.

You could probably make the first argument in favor of, say, gaming binges, drugs, etc., but not the second.