Heart Rate Extremely Inaccurate, Microsoft Says Band is Entry-Level Device

[rockstarzzz]

Ok, here's my result. I was wearing the band the way I normally do (display out, on wrist bone). This places the sensor right on a visible blood vein. I put it in "run" mode with the GPS off. My interest is in the readings you get as a "workout coach", not the graph you get later. So what I did was walk around the mall with my Band and Polar for 25 minutes taking a photo about every 30 seconds. For the last 5 minutes I just sat. Note that that while resting, it tracks very nicely. I also have data as to if the Band HR was locked or not, but I'm not good at figuring out how to graph that in a way that's understandable. Let's just say it was unlocked for 21 of the samples. And not all of the wild differences was when it was unlocked. That big slide from 143 down to 106 was locked. (But was unlocked on either side of it.) So simply ignoring unlocked readings doesn't work.

I did include the graph I got in MS Health. Notice that it's smoothed out. The graph is probably adequate for recording the results, but the display readings have some fairly wild swings.

The first three minutes are the most interesting. What was the activity before you started comparison? Are these devices on two different wrists?

What will further help is the %CV or standard deviation between the two sets of readings. I think you could make a box and whiskers plot which will show the comparison in much nicer way. Although it looks like the Band is erratic in how it shows on the display, the average deviation may not be so bad overall.

I've noticed whenever there is a "jump" or a "fall" in heart rate aka interval training - band takes a 2-10 second lag to notice and keep up with change. But if you do something over a longer period of time without big changes in HR, Band tracks it accurately.

However, my resting HR when I sleep very restfully (the dark purple blocks in sleep tracking) shows that my resting heart rate is 40-43 on average in last 5 days. That worries me.

 

[Nate Silver]

Generally speaking, my Band runs quite closely to my Mio Fuse or Garmin strap, albeit responding more slowly to variations. This while observing the 'live' readings on device. What I do notice is that there can be wider discrepancies in the graphs when viewed after the fact, and I think this is down to differing smoothing algorithms applied by various manufacturers and applications.

I have also noticed a few occasions when the Band just didn't seem to get off on the right foot. For instance, getting into a treadmill activity where the strap will fairly quickly climb to the 120/130 range during warm-up, but the Band seems to be stuck in the 70/80 range. Sometimes pausing/restarting the Band or adjusting position will get it going, sometimes not so much. It doesn't happen often, but it drives me crazy when it does. That's why I always tend to use more than one monitor during activities.

 

[TruPlaya187]

Hi, Just did the test at my desk and also earlier while I was walking and my Band got my heart rate correctly.

 

[DroidUser42]

The first three minutes are the most interesting. What was the activity before you started comparison? Are these devices on two different wrists?

Eating at the food court. Then I got up, tossed the garbage and walked out to the mall and started my walk. About 3 minutes in, I walked up some stairs to the next level. Yes, they were both on the same wrist so I could photo them together for each snap shot, but the Polar is a chest strap device. The Polar is a good match for what I was doing.

 

[rockstarzzz]

Eating at the food court. Then I got up, tossed the garbage and walked out to the mall and started my walk. About 3 minutes in, I walked up some stairs to the next level. Yes, they were both on the same wrist so I could photo them together for each snap shot, but the Polar is a chest strap device. The Polar is a good match for what I was doing.

I think if the first 3 minutes are just walks, then probably like everyone has been noticing band is erratic to routine slow motions but once you get the heart beat going, it is pretty consistent. I tested this yesterday on a treadmill.

I walked 3 minutes - band was out 10 heartbeats vs treadmill.
I then jogged for 3 minutes - band was out by 3-4 heartbeats vs treadmill.
I then ran for 30 minutes - band was only 1 heartbeat out throughout those 30 minutes.
I then jogged for 10 minutes - band was only 1 heartbeat out.
I then walked for 1 minute - band was 7-8 heartbeats out.

 

[Artur Verdini Meireles]

Yesterday I did cardio with the microsoft band and the heart rate was actually accurate around +- 140hb. I chose workout mode.
Today I did a leg session at the gym. I di?nt choose any type of workout but I checked my heart rate many times and was around 70/80hb. Impossible!!! Do we have to choose workout mode to have decent heart rate accuracy?!? The band doesnt seem to be working properly.
I?m regreted that I invested 250€ on the microsoft band. I bought it from Amazon. Do you think Amazon would return my money if I send it back? Thanks

 

[Upstate Dunadan]

The HR sampling frequency and duration is different (more frequent and longer) during exercise mode. The algorithm for calories burned is also different.

If don't select the proper mode, your data won't be accurate.

 

[DroidUser42]

Today I did a leg session at the gym. I di?nt choose any type of workout but I checked my heart rate many times and was around 70/80hb. Impossible!!! Do we have to choose workout mode to have decent heart rate accuracy?!?

In "normal mode" the HR is checked once every 10 minutes. You'd have to select some kind of exercise mode for it to give you real-time monitoring. It's a battery thing. Those LEDs take power.

You can do spot checking without going into exercise mode, but it takes time to lock in.

 

[gadgetrants]

Yesterday I did cardio with the microsoft band and the heart rate was actually accurate around +- 140hb. I chose workout mode.
Today I did a leg session at the gym. I di?nt choose any type of workout but I checked my heart rate many times and was around 70/80hb. Impossible!!! Do we have to choose workout mode to have decent heart rate accuracy?!? The band doesnt seem to be working properly.
I?m regreted that I invested 250€ on the microsoft band. I bought it from Amazon. Do you think Amazon would return my money if I send it back? Thanks

I also have the impression, based on my own workouts and reports here from other owners, that the Band does a reasonably good job tracking your heart rate when you're doing something steady and continuous, like running, cycling, something on a machine, etc. It seems that if your workout is in bursts of activity, like weight-lifting -- even in workout mode -- it's not locking and sampling often enough to track your HR. If you repeat the leg routine in workout mode you should see something better, but I'd suggest keeping your expectations not-too-high.

​-Matt

 

[TwoClipz]

I just got back from the doctors office and checked my band while they were taking my HR.
The Doc said 84 and the band said 81. I don't know what any of that means, but it seems close enough.

 

[DroidUser42]

I also have the impression, based on my own workouts and reports here from other owners, that the Band does a reasonably good job tracking your heart rate when you're doing something steady and continuous, like running, cycling, something on a machine, etc.

My theory is that motion can create interfering "pulses" that throws things off. But the Band uses it's sensors to look for motion that corresponds to the blood flow and tries to subtract out the false readings. But it can only do that if the motion is repetitive for a period of time. A weight machine workout isn't long enough or repetitive enough for it to figure that out.

 

[Boysie1953]

I have just completed an hour workout using the "Exercise" mode. The pulse rate varied between about 70 and 168 even though my work rate was steady. This is completely unacceptable and not what Microsoft are advertising.

Do I send this unit back or is this how bad they all are?

I am a huge Microsoft fan but this is unacceptable.

Pete Boys
UK

 

[DroidUser42]

Do I send this unit back or is this how bad they all are?

It seems there's a large component of individual physiology involved. Same say it does well, others, not so well. You might try a different tightness and/or placement.

Some have reported good luck with an exchange, others, not so much.

 

[kevin shea]

I am trying to do some heart rate based training where I run without letting my heart rate get above a certain level. So far a couple of weeks in it is not very successful. The heart rate on the band seems to fluctuate greatly and often is far higher than my actual heart rate. I have tested it by stopping and feeling my pulse and while I am not a doctor I can surely tell whether my heart is beating 3 times a second. The band shows me over 180 and I am not even close to that. I also have stopped run mode and gone right to my daily heart rate monitor number and it is much lower than the band is showing when I am running. There are times it seems to get synched up and is right where expected and then other times it is way off. I am going to keep testing tightness, location, inside/outside of wrist, ... but not too thrilled with the early tests.

 

[DroidUser42]

There are times it seems to get synched up and is right where expected and then other times it is way off. I am going to keep testing tightness, location, inside/outside of wrist, ... but not too thrilled with the early tests.

Sounds like you're in the same situation I'm in. I find that motion tends to confuse it. It tries to compensate, but it isn't always successful. My personal best result so far is to set the Band to maximum size and then turn it at nearly a 45 degree angle on my wrist. Not terribly comfortable, and it seems rather stressful on the Band, but I get good solid readings that way. It seems that the capillaries in that spot "plays better".

Another way is if I use my Band hand across my chest and hold my shirt. That keeps the arm immobile as far any bending or flexing. But that tends to upset balance.

 

[CernT]

What optical sensor Microsoft uses in the band? Anybody knows the name? It's not the Mio which is really accurate and are in most of the best sport devices from Garmin, TomTom.

 

[willgill]

heart rate on the band seems to fluctuate greatly and often is far higher than my actual heart rate. The band shows me over 180 and I am not even close to that.

My experience is similar. When the heart rate locks, the accuracy is close enough for me. However, getting a lock is very frustrating sometimes. I'm at about 16% body fact, Caucasian, no tattoos and lightly tanned skin. Essentially.... average. ... except for my blood pressure. I'm pretty low and my hemoglobin (and RBC count, HCT) are on the higher side. Hemaglobin runs 16 to 17.2 depending on my hydration.

The only things have seem to improve getting a lock is wearing the band higher up on my arm, towards my forearm and cleaning the sensor periodically.

Things that made NO improvement were: shaving my arms, switching position from bottom to top, wearing tightly, movement or no movement.

 

[tangledW]

My Band is actually very accurate.

When at the doctor, I compared it to their device when they were reading my blood pressure and it was spot on.

 

[gadgetrants]

File this one under: "It's Damn Hard to Read HR with an Infrared Sensor"

Apple Watch infrequent heart rate measurements are intentional - CNET

Most telling:

The company reports that the wearable will still attempt to track your heart rate every 10 minutes, but won't record it if your arms are moving. Users can also still check their heart rates by manually checking its Heart Rate Glance feature, and the device will continue tracking heart rate during a workout.

I suspect the Band is probably doing the best it can (large apparent differences between users notwithstanding) under difficult circumstances.

-Matt

 

[DroidUser42]

My Band is actually very accurate.

When at the doctor, I compared it to their device when they were reading my blood pressure and it was spot on.

Yes, I'm sure the Band is quite accurate - when there is no movement.