I have afib and am also a runner for nearly 30 years. I am seeing a nutritionist and have eliminated caffeine, almost completely cut out simple sugars and breads. I take cardio-zyme supplements and others. Iahve had No repeat No episodes of heart skipping beats, nor do I believe afib since a I have started this. I could go on about this, but look into this and check it out. It is almost like I have gotten my life back.
I have seen erratic readings on my Polar heart monitor, while running, when the battery in the chest strap was on its last "legs". Have you also checked that part of your Polar system?
It is possible that a false high reading from your Polar could cause anxious-driven symptoms. But, you say the period may be 12 hours, yet you can't stop and take a manual HR measurement... not sure what that means, I assume you mean when you stop running the rate drops fast, but you are still able to detect AFib. In my case, whatever my HR is, the Polar jumps around, like between 75 and 90 when at rest, and maybe between 100 and 120 when walking around. This is my Polar "signal" of being in AFib, which is all the time.
Hope you get more input.
My Afib has been milder with the 4 times being short term (less than 12 hours). I usually take an extre Rythmol and magnesium (I take around 300-400mg at bedtime so I take about that much extra. I then try to rest and it will go away in several hours.
The exercise flunctuations have been a mystery. I thought it first the Polar was malfunctioning but I have tried another monitor and it says similar results. I feel like I can not run as well but do not know if it is psychological. I look down and it says 200 and get anxious about it. I have tried to take my pulse but have to stop and walk to do this. When I stop, the pulse goes down to normal before I can take it. I used to be a fast runner but feel I have to stop and walk a lot more now. I wondered if anyone else had similar experiences and if the erratic pulse is Afib or something else.
My experience is that I am either in AFib or I'm not, and that state is not affected by exercise. When I go into AFib, it is 24/7 and doesn't convert until I get an electrocardioversion...but even that no longer works. Rythmol SR 425 twice a day was one regiment I tried, it didn't help stop AFib.
What do you mean "..gone into AFib only 4 times..." are these short term periods of AFib that convert back to sinus?
When you experience AFib, as detected by your Polar, are you able to continue at the same exercise level?