You might not want to emulate elite endurance athletes in that they get too much of a good thing…. That kind of training puts you at risk of atrial fibrillation.

A recent study on this encourages exercise regardless.

https://openheart.bmj.com/content/9/2/e002154

> Conclusion: Although older male endurance athletes experienced an increased risk of AF, the long-term risk of stroke was substantially reduced compared with non-athletes.

True, but I think the commentor is referring to the U-shaped relationship of AF and endurance training.

Higher probability with zero exercise, lowest probability at moderate exercise, but an increase in probability as you enter the extreme territory. In my case, 1000+ hours/year for 8 years led to this outcome

PAFIYAMA. Happened to me at 27yo. Thankfully ablation solved the problem and I'm more or less "cured". Interestingly, I had many ectopic beats post-surgery which subsided once I regained my old fitness level.