Heartrate accuracy amazing but....

[BobBunker]

I've been using my ionic for about 4 weeks now, and overall I am very pleased with it.

Having moved up from a Charge HR, I am amazed at the accuracy of the Ionic's HR monitoring when comparing it with my Suunto chest strap HR monitor readings, which should be 100% accurate.

However, although the average HR and calories correlate almost exactly with my Suunto, I get freakishly high peak HR readings from the Ionic - some of which are physically impossible.

While I'm exercising, I often check the two readings and usually find that the Ionic and Suunto figures are within a beat or two of each other - the Ionic lags behind the Suunto by 10 or so secs, presumably because of the data processing time.

This discrepancy is a bit annoying and I can't see how, if my average HR and calories correlate, why doesn't the peak figure also agree?

Otherwise, with some reservations, I have no regrets about buying the Ionic.

[SantiR]

@BobBunker Welcome to the Fitbit Community! Thanks for sharing your positive feedback about Fitbit Ionic and for posting the situation with the heart rate readings. 

By any chance, are you getting those high peak readings at the beginning of your activity? 

I've seen that before, on this thread, and the first thing to try just to check what exactly is going on; is the wrist placement you are using with Ionic. Please check this helpful article for more details.

If you are using the correct placement and still getting those readings, let me know.

Also, if you could share a screen shot of the heart rate graph would be very useful!

Thanks again for sharing your experience with the Fitbit Community. Keep me posted! 

[BobBunker]

 Hi Santi

Thanks for the advice.

See HR track with an impossible peak - my theoretical max is 152 🤔. As you see, it’s not at the start of the session.

However, having read a few posts on the subject, I tightened the strap one notch, and shaved my wrist under the Ionic, and today got a perfect correlation with my Suunto chest HR monitor - by perfect I mean a difference of one beat on average and max, and just a few calories difference.

Lets see how it goes.....

[SantiR]

@BobBunker Thanks for your reply and for sharing that screen shot.

Yes, I see the peak is high for you in that graph.

I'm glad that you got a better reading by tightening it up a bit and shaving. It should give accurate data if the correct placement is being used.

Something to also take into consideration is not wearing the watch too tight nor too loose on your wrist. Also, wear it a bit far up your wrist (two to three fingers from your wrist bone). Blood flow is stronger there so it should give a more accurate reading.

Hope this helps. Let me know how it goes! 

[BobBunker]

No, Santi, since that one good reading, on all my subsequent spin sessions I got  that pesky false peak. Average HR and calories still spot on compared to my chest HR monitor.

Very frustrating, as I would love to be able to rely on the Ionic and ditch my chest strap.