View Full Version : heart rate inverted spikes (drops) in 8-10min intervals

06-03-2012, 09:50 AM

hoping someone here can give some insight into a peculiar thing... i'm an active cyclist for 8+ years, and took up running 2 years ago.

i have a very wide heart rate spread: 48 resting, 214 max. heart rate recovers quickly post exercise.

on my runs, i start out with a nice steady climb to about 170, and then stabilize there. however, about every 8-10 minutes, i get an ~ 20 beat drop and recovery to the 170 level over about a 20-30 second time period. in the file, it looks like a smooth climb from normal to 170, and down-spikes of 20 bpm every 8-10 minutes, like clockwork. it's been like this forever, and with multiple units (garmin, timex, etc.), so i don't believe it's equipment related.

any thoughts?

thanks in advance.

08-10-2013, 03:13 PM
I have the same condition! I found your post after searching the net for a periodic heart rate drop.

I've only used a Garmin (for years) and assumed it was a hardware/software bug. The frequency of the heart rate drop and the recovery was always consistent at around a 10 minute interval, 20-25 bpm with a recovery time of around 20 seconds.

This week I had my wife wear the Garmin and heart monitor for the first time. I was surprised when I did not see the repeating 10 minute drop in her heart rate!

Have you learned anything more since your post of 6/3/2012.

Thanks in advance

01-15-2014, 02:45 PM
I found this thread after some searching for heart rate drop. With my new FR620 I have started monitoring every run and see the exact same drop in exact 8-10 minute intervals. Looking back at older workouts using endomondo and the "old" HRM strap I can see the same pattern. Do we all have some hart condition (unlikely) or is it hardware/interference related? I always run with my smartphone and there could be something with it's data transfer..