Blaze HR accuracy question

[djurden]

I prevoiusly had a FitBit Surge. While running or walking, the device was very good at tracking heart rate. But any other activity; biking, weight lifting, jumping rope, HIIT workouts, etc. (basically any activity where I used my hands and bent my wrist); it SUCKED. Most of the time it was not detecting a heart rate all all. I tried wearing it higher on my wrist and all other suggestions I could find. But I could not get it to accurately track my heart rate during these other activities.

I ended up switching to a competitor's device and it is 100% better at tracking during these activities. But I really like the FitBit apps and other features compared to all other competitors. So I am willing to come back.

So my quesiton is...Does the Blaze have this same issue? 

[AdamMSC]

I never owned the Surge, but I can comment on the Blaze. First, I want to start by saying that my review of it certainly isn't a professional one, but I have tested it against a Polar Chest strap and had good results. For an objective view, you will also want to look at the following videos/ articles to see if it fits your needs: 

Rizknows: https://www.youtube.com/watch?v=BpyBTjfm2TA (4:10 for hr monitor review)
techyagent: https://www.youtube.com/watch?v=PDmAwoGRkTU  (3:45 for hr monitor)
DCrainmaker's comprehensive review: http://www.dcrainmaker.com/2016/03/fitbit-blaze-depth-review.html

My personal testing and results are here: 

https://community.fitbit.com/t5/Blaze/Blaze-vs-Chest-Strap-polar-H7-A-review/m-p/1240131#U1240131

[SunsetRunner]

Didn't have the Surge but did have the Charge HR, and the Blaze has similar limitations; it's good for the day to day tracking but so far, in my experience, it struggles when tracking high activity exercise. I've not given up on it yet, as on occasion it gets it right but more often than not, it doesn't.

[djurden]

Thanks for your replies. After viewing the video reviews and reading the detailed text based review, I have decided to keep my current device. I have compared it with a heart strap and it is pretty close in the heart rate tracking to what the chest strap tracks for all workout types.

Plus; on the non-workout features; it far exceeds what the Blaze does. So...for now...I'll stick with what I'm using. 

[robertthebob1]

From my review on the Consumer Reports page:

In a two week series of four mile runs, I measured the Fitbit Blaze heart rate accuracy against two chest strap ECG monitors, the Omron HR-100C and the Polar H7 (the same sensor used by CU) at three tightness fittings, just above my wrist bone, each differing by one band notch. After a ten minute warm-up: the least tight; tighter; and most tight fittings showed an average difference (X) from the Omron and a standard deviation (s) of 0.6, 2.4; 0.9, 1.6; and 1.0, 1.5 beats per minute (bmp), respectively. The overall X and s using the Polar H7 with the most tight Blaze band fitting was 1.2 bpm and 1.0 bpm, and in relatively high intensity (for me) runs between 140 and 150 bpm the X and s was 1.2, 0.6. It was not necessary to stop and let the Blaze readings settle before recording numbers. The most tight fitting was not as uncomfortable as the chest strap during a run. The conclusions are that: on my wrist, the FitBit Blaze must be quite tight to obtain an accurate reading, it is within 2 bpm of the Polar H7 most of the time, and it maintains this accuracy at least up to 150 bpm with no change.

My suggestion is to view the FitBit from the hand-side and push up on the band from the bottom with your thumb and index finger. If you see green light, the sensor is subject to light leaks and movement artifacts and the band is not tight enough for strenuous exercise. I've not had a problem with reduced circulation, and it appears I could go even tighter. In my preliminary tests in exercises where the wrist is flexed: push-ups, weight training, and bike riding, I've seen very good results, but I have no statistics yet.

[J-flex]

@djurden - I have a Blaze and the heart rate is not accurate. When I want to monitor my HR I use a Polar chest strap and that is 100% accurate. I too have a Surge and the HR rate on that isn't accurate either. I do love the challenges that are part of Fitbit.

[robertthebob1]

Do you see green light or space at the bottom of your fitbit when you push up on the buckle of your strap with your thumb and index finger?   Did you read my answer?

[J-flex]

There is no green light or space at the bottom of my Fitbit.

[robertthebob1]

When I write "push up on the bottom of your band" I should have said push up on the bottom of the sides of the band instead, to lift the watch bottom if possible.  Then tell me if you see a green light.  You should also see very little daylight between the band and your wrist at its attachment to the watch.
BobSent from my LG G3

[RobSaxe]

I've had the blaze for two weeks. Mine has the blinking green lights on the back. I've tested the heart rate manually, taking my pulse and watching the reading. It's been within a beat or two everytime I've tested it. As far as my p90x workouts, the calorie count had been slightly lower than the online calorie burn calculators but that's ok with me. The heart rate has been comparable with my bowflex watch as well.

I love this thing...

[robertthebob1]

Then again,  if  you've already tried tightening your FitBit by two notches before runs and still don't see accurate heart rates, the problem may be that your skin type is very non-photosensitive and absorbs most of the green light that is scattered back from blood carrying tissues.  In the scientific paper, "Validation of photoplethysmography as a method to detect heart rate during rest and exercise", J Med Eng Technol, 2015; 39(5): 264–271, the authors observed that this technique can be greatly influenced by skin photosensitivity, and some people with very non-photosensitive skin my need to stick with a chest strap.  The research reported in this paper did not directly address skin photosensitivity, so more real research needs to be done here.   The only other reason I can think of right now why a FitBit heart rate sensor might be inaccurate (given what I've measured with my Surge and Blaze) would be a lemon sensor.   You could have a friend with light skin test your FitBit against your H7 to see if there is a difference.   I need to collect some statistics where my wrist is flexing...