Interesting thing I saw on my training today.
This was a long slow and endurance ride.
For no reason in the middle of the ride, several time - my heart rate went down 15-20 BPM.
I actually looked down and saw it the first time because I felt great and energized.
Thoughts?
PS This was verified with both a heart rate strap and my apple watch. The HR was the same during the drops.
How is it being measured? What device?
Could mean you are super fit.
Could mean the device isn’t on properly.
Could mean the device is malfunctioning.
I’m a little overboard with data. I measure with a ring and wahoo arm band.
Two scales Withings and Tanita.
Ring for sleep data and Withings sleep thingy. I’ve tried 2 pair of dual sided power meters. Turns out no way to do that.
I do apologize. I forgot that detail. I had a HR strap on and an Apple watch running.
Both agreed during the drops.
What were you doing during the episodes? Did you go into the drops? Put your head down? Cough/sneeze? Swallow food? Feel gas pain and then fart? Etc. Any of those things can easily drop your heart rate by 10bpm during very low z2 work.
Maybe a little 
Went down from 80 to 75-60? Or was 15-20?
Admittedly, I’ve never been that low that I know of. But will definitely hangout in the 40s. 15-20 seems low but I do software. I’d say you are super fit. But I also would ask your doctor.
Super helpful huh!
Dropped from 135 to 110ish.
While quick I do see random drops in power. That might be related?
I would agree. Looks like you stopped peddling and started changing the channel looking for Taylor Swift.
If power was constant perhaps a different conclusion?
What’s your favorite era? For me it’s either Reputation or evermore.
No clue! 70s and 80s Barry White and podcasts?
I keep going back to reputation
Could either be microbreaks (I see cadence dropping) or dropouts or an issue with your heart rate monitor
Electrically interference affecting both devices, just because they both show the drops doesn’t mean it is valid data, (and interference the reason for the power drop outs?)
None that I could detect. It was enough times (I am guessing about 10) that I watch to see.
I didn’t drink or coast prior (though you can see me coasting once it happened as I was checking my watch and head unit).
I couldn’t connect anything and this was an indoor trainer as well.
If I kept seeing this across 2 HR monitors, I’d start to wonder/read about afib.
A complete stab in the dark @CyclingPhotog are both HR monitors and the PM/ Trainer using the same protocol. There’s maybe some sort of micro-interference in the Bluetooth/Ant + signal.
They are not. One is ANT/Bluetooth and the other is a direct sensor. And the two are not connected.
There’s probably some simple sort of interference thats affecting them all that I’m missing, but for your own piece of mind you might want to see a doc. Good Luck!
Yeah that looks nothing like silent afib, tachybrady, nor brady secondary to afib (both of which are absurdly rare). I get it’s cool to use medical terms but fearmongering some poor bloke isn’t kind.
Op; did you actually feel anything weird simultaneously or at a point on the ride? Chest pain? Lightheaded?
All of the drops look exactly the same and look exactly like a normalised dropout (drop in rate, an interpolated beat, then a long wait before it kicks back in at normal rate).
