Just read an article in The Australian newspaper saying excessive exercise can cause arrythmias incluing AF and too much exercise is bad for your heart.
They are talking about people who are gym junkies doing two or more hours workout . I used to do long distance running and now I'm wondering if that caused a mildly dilated left atrium that I've got now.
Good news for some of us who are fairly sedentary now 🤔
Yes this is well know and yes probably your running is the reason. Over working the heart causes it to expand to cope with the demands . Excess exercise bad, no exercise bad. Life is about balance in all cases. A glass of wine with dinner is fine but a bottle is not. Seven times a night is too much. You get the message.
This is the part of the "overtraining syndrome". Temporal detraining sometimes help the regression of the dilated atria.
Here you can find some description:pmj.bmj.com/content/81/951/62
Metoprol and arrythmias
Its becoming too much to bear.
How much exercise is safe with AF?
How much flecainide is too much for afib?
What’s too much post ablation 
