HR Accuracy of Vivosmart 4

If you're going to use 935 for all day do you change the preferred tracker? Or not?

Thanks!

yes, I will.

HR from wristbands always have a lot of trouble cycling. fitbit, garmin, etc its a common issue

Exactly. Heartrate detection through a wristband is ok for low impact training such as walking. As soon as you go beyond 120bpm it's hit&miss. For serious sport there's no substitute for a cheast band. I use my Vivosmart for 24/7 monitoring (steps, heartrate, sleep etc.) and use my Fenix 3 when I do cardio, cycling, running etc.
There's no other brand that's better than this. Maybe Fitbit is a bit more accurate, but when the heartrate goes up, it's the same story. Unreliable.

Exactly. Heartrate detection through a wristband is ok for low impact training such as walking. As soon as you go beyond 120bpm it's hit&miss. For serious sport there's no substitute for a cheast band. I use my Vivosmart for 24/7 monitoring (steps, heartrate, sleep etc.) and use my Fenix 3 when I do cardio, cycling, running etc.
There's no other brand that's better than this. Maybe Fitbit is a bit more accurate, but when the heartrate goes up, it's the same story. Unreliable.

Thanks Mike.

I had a treadmill stress test yesterday, while connected to an ECG. The ECG reported my heart rate increasing gradually to 155 over several minutes. Vivosmart 4 didn't get above 110. Useless for monitoring high intensity exercise.

Have to say that I agree, i'm a cyclist, usually use a chest band, so just did a static ride, and held 165-170 for 35mins +10min of warmup and cool down on either side,(recording on chest strap and garmin 520plus), the vivosmart 4 had me maxing at 145, and had a 25mins gap where I was at 70-80bpm. The body battery has changed in line with the vivosmart4 readings. Will try next time with it on a profile and see what happens. I suspect similar to the above posts.

I've had a similar experience cycling, though, interestingly, only since firmware versions after 2.40. When I first got the Vivosmart 4, the hr curve while cycling (in motion outdoors) seemed reasonable, though I didn't have a chest strap for comparison. Since fw v2.40, I now routinely see sharp changes in measured hr, usually either periodic dropouts or a jump (to what I suspect is a more accurate reading) toward the end of my ride, very rarely a low reading throughout.

I've likewise seen reports that nearly all bands have this issue with cycling (and it seems to be cycling specifically, rather than high hr generally; my guess is as a function of the continuous vibration disrupting the optical metering of subcutaneous changes), so I was pleasantly surprised by the initial performance. It's entirely possible that was a fluke or that it WAS measuring low but I didn't realize it, so don't take my report at face value on its own, but if it's consistent with other reports, it could point toward a code change that made hr monitoring during cycling less consistent.

P.S. I'm VERY light-skinned and freckled (homozygous nonfunctional MC1R receptor mutation type) - I know skin pigmentation can impact optical hr sensor performance, so I thought I'd mention it.

I've been wearing my Vivosmart while participating in an exercise program involving step stair, stationary bike, treadmill. As someone else suggested, Vivosmart is poor at recording heart rates over 110 and usually misses rates over 125 altogether.

I've been wondering about this, too. I run, and my Vivo4 has me at 168-175 bpm. If this is close then great, but if it's way off, as in reading higher than actual, it's not really doing me any good to wear it for my runs. I doubt it's reading lower, because I'm not a fast runner. It stays consistent in this range, but I'd really like a more true idea of my hr, for the sake of fat burning vs. cardio zones.

Yesterday I compared my Vivosmart 4, a Garmin Edge 704 with chest strap (ancient but accurate) and a Computrainer with the earlobe attachment. The latter two were within a couple of beats of each other at all times and looked right. The Vivosmart 4 was about 50 beats low on the first interval! After that I rotated the device to the inside of my wrist and got good readings. For a third interval I put it back on the outside and continued to get good readings. Now I don't know whether it was timing, position on my wrist, or some third factor that made the difference.

By the way, these are not short high intensity intervals. There is plenty of time for my heart rate to rise and stabilize and for the devices to measure the changes.

What I really want to know is whether the 2.90 firmware update which came through yesterday will make a difference. The notes say "Heart rate improvement", but there is no indication of what is suppose to be improved.

I'll still use a "real" heart rate monitor for serious exercise, but I would really like to be able to trust the Vivosmart to get things right when I go for a brisk walk. Thinks like "Body Battery" can't work very well if the device ignores all hard efforts.