Any update on heart rate accuracy issues?

[askinstuff]

Hi. I purchased a sense within a couple months of release. Compared to Polar heart strap, Samsung active 2 and a pulse oximeter. The pulse

 oximeter and the polar strap remained within a couple of beats at rest and with activity. The Sense though, OMG was it off! Your talking up to 20bpm or more with exercise.

I had an ionic which was great, but lasted only till right after the warranty ran out, and heart rate was pretty spot on.

Given that previous Fitbit watches were accurate, I'm assuming this is something fixable.

Having said that, had there been any software or hardware update to fix it? 

[Dc00121]

I'm having the same issue. Extremely frustrating 😑 

[MagisterMundi]

Apparently they've been aware of it since shortly after the launch of the Sense, so given it's been more than a year without a fix, I suspect it's a hardware issue, not a software issue, so not fixable. It really is quite bad, though, I agree - my heart rate can be as high as 185 or more and the Sense says it's 151 or something ridiculous like that. Seems accurate up to the 150 range, though.

[ngc2359]

Oddly - because my HRV shows as in the 20's (lowest at 15) ... and I exercise 6 days a week - the 'average' for my age should be in the 60's I bought a Polar H10. Elite HRV showed it as 52 (first time use). Then I compared my heart rate using the H10 to the Sense. WOW. The H10 is the same - exactly - to the HR monitor built into the treadmill ... around 95 at a fast walk ... the Sense? It is showing 130! So I seem to get the opposite of most other claims of inaccuracy showing higher numbers, not lower. I've seen as high as 150 (on the Sense) but now wonder how accurate that was. JUST got the H10 so more to see especially re HRV which greatly concerned me. 

[t.parker]

@ngc2359 for me, Sense usually gives higher reading for walking/low-intensity activities and gives lower readings for medium/high intensity. For the treadmill, mind that lots of machines connect to your strap and capture HR automatically (using ANT+). Most of gym treadmills will do it so what you see on the treadmill may be in fact PolarH10 reading.

[eezeepee]

https://youtu.be/qt7hBdddCrw

This guy tests devices objectively compared to things like EEG (for sleep monitoring) and a Polar chest strap (for hear rate). His findings were that cardio exercises like spinning and cycling were more accurate than weight lifting. Also, there's been a delay in the Sense picking up heart rate change and sometimes it doesn't hit the max. Updates have improved the heart rate max readings and the delay is shortened somewhat but it's still not as accurate as a Polar chest strap. I think he also compares it to other Fitbit monitors. For me and my moderate interest, it's good enough. He also notes, it could possibly vary from person to person 

[Dc00121]

Iv been using fitbits for a number of years now, with the sense my heartrate never got over 100bpms(vigorous workouts), using a charge 3 I was averaging 125bpms. Somethings not right with it. 

[eezeepee]

I was able to hit a high of 179 BPM yesterday. It was the first time I had the band one hole tighter than what I comfortably wear when not working out. Too early to know if that truly made the difference.