Mine are really all over the place. At first I never had them during the night, but by the 3rd year of a fib I occasionally would wake up in the middle of the night in a fib. I have had them start in the morning, after lunch, but probably more typically late afternoon. Exercise triggers them for me also. Usually will start as soon as I stop exercising, but have had it start in the middle of yoga class, and while on the treadmill. I believe mine are mostly related to adrenalin/stress, but then I seemed to develop a vagal component also.

Mine are all at night, when trying to go to sleep. Never happen when laying on my back, only on my sides. I have vagal afib which is medicated differently than adregenic afib. Beta blockers make vagal afib worse. Glad I finely found this out as Sotalol was making me worse. Good luck to you:)

Oh, I forgot to add the in addition to afib epsidoes in the early evening when I being to relax from the days activities, I almost always have a short episode when I lay down to go to sleep. Go figure.

Mine can be at any time. I've only had a couple at night. A lot are when I exercise, or am under stress (i'm so sensitive to adrenaline. In addition to the Afib, it drops my blood sugar and exercise triggers my asthma too.) I have noticed episodes at rest too. For me they last about 3-10 minutes with symptoms and they are very spontaneous. I have good control with meds.

Mine are when I go to bed at night. I exercise 6 days a week at the gym and never get them there even when my heart rate goes up to 150 on the ellipticals. Strange!

My afib usually starts in the evening after dinner while I am relaxing, go through the night and convert some time mid morning. I am surprised, but I usually can sleep right through it. The only time I couldn't was shortly after my ablation when I had one episode of rapid heart beats and I had to go to the ER.

Exercise too does not bring it on, but if I am walking outside in the heat and I feel the stress, it too can bring on an episode.

Anything that raises my heart rate semms to triggger it. I had the flu with fever and your heart rate is more rapid when you have a fever...I believe that is what triggered it. Also vomiting. I have had a stomach bug (thanks to grandkids) twice this year and as soon as I threw up...into fib.

although I have had Afib for nearly two years, it is only lately that I am more aware of the tell tale heart beats. I exercise vigorously and do not feel any effects from Afib. at rest - as in lying down to go to sleep - would be the time I would be most aware of an irregular heart beat for any period of time. during daily activities there might be a slight "flutter"; but it is at night that short episodes (not lasting more than a minute or two) become noticeable.
I am curious, what do most people use to specifically check their heart rate? because my blood pressure is on the low side I do not use my monitor, which also shows heart rate and irregularities, very often. does anyone use a heart beat monitor or do you simply check and time your pulse manually? Rich