I've been exercising quite a bit more frequently, bicycle racing actually, and now I've come to notice that my heart rate hasn't been regular lately.

I've always had a low heart rate due to both exercise as well just having a big heart. And I can remember that when I would check my pulse manually, and then even in recent years, that my heart seemed to beat fairly evenly.

The other day, I checked my resting HR by using a heart rate monitor and discovered that my heart was beating irregularly. The monitor was displaying a bpm range of 33 to 44 - with an average of 38. (this was in the morning at rest)

I confirmed the 38bpm by taking my pulse manually, and was quite shocked that indeed I could sense the uneven heart rate.

I know for a fact my heart doesn't behave this way all the time. I can remember years ago watching my heart rate monitor fall to 37-38-39 and beat within that range for minutes at a time.

So what "kind" of bradycardia is this? Any links to info about what "range of bpm" constitutes an irregular rhythm? I think I may experience the same effect during exercise also. Instead of a near steady rate with a variation of 1-3 bpm, the heartrate will jump around as much as 6 or 7 bpm......ie

Instead of 133-136, I'd get jumps of 130-139, for any given upper range.

Thanks to some helpful people elsewhere, I finally got an answer to my question about heartrate rhythm deviations.

Apparently, deviations exceeding 10% of a given heartrate are considered abnormal. In other words if you have a resting heartrate 60 bpm, then experience rapid changes that exceed 66 bpm or "dropped beats" that cause your pulse to display as low as 54 - then you may have problems.

Of course, I learned of my heartrate abnormality from a heartrate monitor. THe standard advice for anyone experiencing these kinds of rhythm changes is to get an EKG. Thanks to the folks at HealthCneterOnline forums.

However, thanks to all for some of the previous advice.