HR monitoring accuracy - unacceptable

Mine does the same thing, although it usually locks onto my actual heart rate after 10 minutes or so. It is absolutely unacceptable. I can't trust the readings I get from my device because it is so often completely inaccurate. There are several other threads on this subforum about the same problem. I hope this is something that that Garmin can fix with a software update. I really like this device, but its main feature (HR monitor) is not very useful in its current state. I guess I will contact support so that they at least are aware that people are having problems.

AlexCh - first, congrats on a strong 2k time! :)

I just received my vivosport 3 days ago. I went for a brisk walk yesterday and noticed that the calories were a bit off from what I got with runtastic on the same distance. Then, later, I performed a tabata KB swing and just chose 'other' and was surprised at how low my HR was (117 bpm). I figured it would have been a bit higher.

I'm about to hit a HIIT for about 15 mins or so, I'm going to make sure that the device is tight enough and in the proper location and see if that makes a difference.

Seeing that the bpm registers a little more correctly after 10 minutes makes it seem like a software issue. Meaning - the device has proved that it can read the HR, but it takes time for those readings to take hold ... ?? idk - just throwing out opinions.

So ... test performed.
I started with about 3 or 4 minutes steady warm up on a stationary bike. For the first minute, the HR indicator stayed at resting (72 ish) while the stationary bike ramped up to like 98. After a minute or two, the vivosport quickly climbed to be close to the stationary bike readout. I made sure that it was snug and above the wrist bone.

I then performed a routine of 14 minutes broke out into two minute incremements with no rest:
1 min jump rope (single unders)
then 4 R and 4 L KB Dead Lift, Row, Clean and Press, then would rest the ~20 seconds until the next two minute interval.

My HR rose to around 135 after the first round and then up to 150 and even 160+. There was a round where it dropped down to around 130s, I think this is because I tightened the strap due to it moving around a bit. It then climbed again.

Maybe your wrist device wasn't properly positioned and tight enough during your activity?
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Hi gannimal007

Thanks for your sharing your experience so far.

I am encouraged to see your HR above 175. I have completed two more maximum-effort ergs since my original post and again the device has been around 40-60 bpm lower than what I expect to see (maximum recorded HR being 121). At some stage my device has recorded a maximum of 161 bpm with passive monitoring, but as this was not during my timed exercises, it is still incredibly disappointing.

I am aware that HR monitoring on wrist straps can be notoriously inaccurate, however I had hoped that so long as it is consistently inaccurate, I might still glean some meaningful trends from the data. At present this isn't possible, which again, is very frustrating and something those thinking about buying the device should consider.

I will experiment with my device positioning. My first two rows in the original post were 'normal' tightness (i.e. snug, but no discomfort). My latest two rows have been extra tight (i.e. causing mild irritation and adjusted immediately post-exercise). This doesn't seem to have improved the results at all. One thing I find disheartening is that during my warm down the device was recording a HR of between 60-70 (while I could feel my heart beating out of my chest). I removed the device and waited for the HR to reset before attaching it again - it displayed the same numbers as soon as it picked up my HR (one might argue that must be my HR, but it doesn't seem conceivable).

I will experiment with the wrist positioning. The startup tutorial told me to wear it below my wrist bone (towards my shoulder) which I have been doing, but note yours was positioned above the wrist bone (presumably you mean towards the hand?) - I will try this and report back if there's any meaningful change.

If anyone has any luck please share your experiences! The HR monitor seems fairly accurate when resting/walking. I noted in one review (of the roughly 10 I read/watched before purchasing my device) that one user reported accurate HR monitoring during running, but completely meaningless results during cycling - this might suggest that, despite being tightly fitted, the device struggles with exercise involving wrist movement? I note however that gannimal007 seems to have recorded meaningful data during what looks like quite an intense weight circuit, so this theory doesn't seem to hold.

Cheers

A

I agree that this is most likely an issue that can be corrected in software (that is, if we can get Garmin to recognize that it exists). This issue does not happen every activity in my case, however it does happen relatively often and its inaccuracy makes it difficult to trust a device that reads 50 BPM low when it feels like it.

Here is an example. As seen below, my pace did not change, nor did the elevation, yet my heart rate reading shoots up after 8 minutes or so. I checked my heart rate with another device during that period that the Vivosport was reading low, and indeed my HR was about 50BPM higher than what was displayed. Since I knew that the vivosport was reading incorrectly, I made sure it was suitably high up on my arm and very tight. That didn't seem to change anything.
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AlexCH - Above the wrist bone means closer to shoulder (to me at least lol);. When I first wore my device on a brisk walk it was closer to my hand and I had a suspicious calorie read out. I went for another brisk walk last night with the device positioned as instructed, used the GPS feature, and the calorie, HR, and distance all seemed within normal ranges.

You have me very curious. I'm going to row today for my intensity minutes and see how my device responds. One thing that I did yesterday when my HR readings was acceptable was performed a 'warm up' of sorts. During that time it took my device a couple minutes to climb up from resting to moderately active. I then went straight into intensity.... maybe jumping from resting to intense has confused the device? idk .... just my experience. YMMV. I'll report back after my erg session today.

Another test in the books - not good results. I did erg intervals at 1:30 at a moderate/quick pace (around 1:50 split avg) then :30 at about 2:15 split for 20 mins. At times I was above 1:45 split which means this old man was pulling with some power.

I chose the 'cardo' activity. During the entire session - my device never measured my heart rate over 100 bpm - usually around 90 ish. When I finished the 20 min erg - i went to the stationary bike and after about 2 min on the bike (22 min into my session) - the device started measuring my heart rate more accurately. See graph below. When I finished the erg - my device measured 115 calories and the erg measured 310. BIG discrepancy. ciq.forums.garmin.com/.../1299865.png

I have the same issue. Last week I did some gym sessions in a hotel, where the gym was quite warm, and the HR locked on pretty quickly. I am currently using a Polar HR chest strap (which has polar and bluetooth) in addition to the vivosport. The Polar as you might expect can assumed to be as accurate as you can reasonably get. But my sessions in my home gym (much colder) have exactly the same problems discussed here. Either about 10 mins to suddenly match the Polar reading, or not at all during 30 mins. Taking the dog for a brisk walk for 30 to 40 mins works just fine as far as I can tell.
I am pretty sure it is a software fault. I have seen the HR reading accurately (above 160, and matching the Polar), I think there is some data smoothing that is going on, that is probably dependent on the activity selected.
Would be good if Garmin came out with a statement and acknowledged the issue on this expensive bit of kit.
Otherwise it is a great tracker

I chose the 'cardo' activity. During the entire session - my device never measured my heart rate over 100 bpm - usually around 90 ish.

Thanks gannimal for sharing your test! I am erging everyday at 100% intensity and yet to record an average HR above 100bpm. My highest HR recorded is 143bpm, but looks more like a blip on the graph. These results aren't remotely accurate for the work outs I am doing. For what it's worth, below/above the wrist bone hasn't improved the results nor different band tightness - I am going to try on the other arm but doubt this will change anything.

I haven't performed enough variety of exercise to comment on the 'software issue' theory but generally agree that the HR monitoring seems realistic at rest. I am yet to see the rapid increase in HR described by other users at the ~10 minute mark. Mine simply never increases to an accurate level during exercise (tested up to 1 hr duration) nor during my warm down. I want to say there is something in the rowing stroke motion which throws off the device, but this doesn't explain why it shows a HR of 60-70bpm immediately post-exercise during warm down.

Let's see if a firmware update can improve the issue, but this performance is very disappointing for a premium activity tracker. I have had my device for just over a week now, and am starting to think about trying to return it :(

Alex

I did a workout the other day where I alternated between kettlebell swings and jump rope. When I was jumping rope, my heart rate was accurate, when I was swinging the Kettlebell, it would drop 30 or 40 beats. I think the sensor has trouble picking up the heart rate through a flexed wrist muscle.

try a test where you turn the Vivo sport around and it reads from the underside of your wrist. I'm going to try the same thing on my next kettlebell or ERG workout and see what happens. Today, I went for a long run and it was accurate through the entire run. I think it has something to do with the flexing of the forearm