Originally Posted by terrymorse

Yeah, what really causes Afib in older endurance athletes? It sure would be nice to know, medical science folks.

The general term thrown around is "it's inflammation". Yeah, thanks, that's helpful. It's inflammation that induces fitness improvements, so it's a "god thing" in the right amount. But what's a "not right" amount then, and how can we tell if we're in the danger zone?

As far as I can figure, "Afib-causing" inflammation is severe enough and lasts long enough to produce scarring in the heart. The more troublesome activities reportedly are exercising when you're already sick, and failing to rest adequately between harder workouts.

I'm putting in more endurance pace rides, riding really hard only once per week, eating healthy, and getting lots of rest. Hope those are the right doses of everything to keep the heart happy.