HR accuracy when not in activity


I received my venu 2 5 days ago and noticed a lack of accuracy In HR monitoring mainly when not in an activity. If I start an activity it seams to go fine when compared to a band, but during the day is always around 65-80 even when I’m band is around 110 or more. 
also noticed that during if I’m cycling and in the edge I see 135 hr, in venu (without starting an activity) it’s still at 80.

anyone else? This is anoying and I might send the watch back.

thank you

  • All-

    For the most accurate heart rate when doing an activity, we recommend recording the activity on the preferred activity tracker (that you wear all day or to sleep) even if you discard the activity at the end. 

  • Cheers for the update Kevin... We've pretty much all figured that out already.

    Do you have a technical reason as to why though?... Does the HR sampling rate increase once an activity starts etc?

    I'm guessing it's something to do with saving battery usage in everyday HR mode vs during an activity?... Which is understandable, but would be nice to know the specs as to what's happening under the hood so to speak. 

    I've already got an Edge 830 to record my cycling training on... Remembering to record on the Venu 2 also - just seems a bit pointless.

    Thanks again. 

  • Thanks for your answer Kevin!

    I appreciate your response.

    However, unless we go with the saying “it’s not a bug, it’s a feature”, starting an activity each time one requires an HR reading defies the whole purpose of providing a device with continuous HR monitoring. 
    I guess most of us would like to know if, while not in an activity, it makes any more sense to keep the HR turned on while this issue is being addressed?

    Thank you,


  • i used to broadcast my HR via Venu 2 to the Edge 530 and it seems to work fine and precise. I was actually surprised how precise it is

  • This is good to know, but I think this can also be because of the nature of the use case. Difficult to tell without more data. In my experience, the HR was also good when the watch was working on a particular activity (running in my case), but not that accurate if I didn’t start an activity ( e.g while walking the HR was quite a bit off).

  • I have Venu 2 and the same problem. Today i did indoor ride and HR with belt is 160 but on the watch 80. So something is wrong. 

  • I believe the sensor is underpowered in continuous HR monitoring outside activities.  Properly powered, the sensor does a good job. But you’re right, even if this makes sense to save battery, it isn’t what you would expect. 

  • i always broadcast my HR to my edge bike computer, i did that with the venu2 and the forerunner 55. I also checked the accuracy a couple of times while working out with an additional chest strap. Seriously, there is lots to blame about the accuracy of many other data like spo2, hrv etc... but i find the HR accuracy surprisingly good. 

  • I have the opposite problem, not only with my new Venu 2 but with my previous Vivoactive 4.

    When I'm in activity, everything is fine and the sensor measures very accurately, especially on Venu 2.

    But when not in activity, but not in full rest, almost always measures 10-20 beats over my real heart rate.

    So, for example, I'm working on my computer and the watch is showing 75 bpm. If i suddenly stand up and start walking in my home, my real bpm measured by other devices would be 80-85, but Venu 2 measures about 100-110. When I sit down and rest for a minute or two, it starts to be accurate again.

    Sometimes this bug is so annoying because the heart rate on Venu 2 goes sky high, for example, 120-130 bpm when walking very light at home, but my real hr is about 85.

    In my experience, there are 2 ways this can be corrected, at least temporary.

    While I’m walking, I can:

    1. Turn off the sensor for 1-2 seconds from the Settings menu and turn it back on.
    2. Activate the heart rate widget and leave it like that until it automatically goes back to the watch face.

    Both of these make the sensor start measuring right, at least for a short period of time.

    The second point makes me think that while at rest, the sensor goes in some kind of low power mode, which is okay at rest, but not good even at a very light activity. When I activate the heart rate widget, this pushes more power to the sensor and it starts measuring right.

    And this bug is like that at least for a year. I’ve got it on my previous Vivoactive 4 for a year and I was hoping that the new sensor on Venu 2 will fix that but sadly it looks like its software/firmware problem spread across multiple devices.

    So, in the current situation, I can rely on my heart rate data only when I’m at full rest or when I’m in activity mode.

  • So basically every time I walk to the super market, bike to my gf for three minutes or even just a stroll through the yard you want me to start an activity? Otherwise the hr readings will be inaccurate. I thought this was a "smart" watch.

    This is unacceptable for a 380 euro watch.