Suunto heart rate strap only works when pausing and un pausing the current activity

[peringmar]

Before starting an activity the watch finds my heart rate strap instantly. But when I hit record the heart rate will not be displayed correctly. It will display a low value regardless intensity.

First when I pause and then unpause the activity the heart rate will show correctly. Does someone else have the same issue? If yes what watch are you using? Maybe this does not just apply for the Spartan and if you have the same problem, maybe try this trick.

In the screenshot below is an example of the issue. For the first manual laps the heart rate is displayed wrong but at lap 6 after pausing and un pausing the watch it is displayed correctly.

Could this be a bug?

Here is a better image showing the problem.

[surfboomerang]

@peringmar I have never seen this with my S9B combined with HR strap. Just to be sure… the watch itself is also showing incorrect values or is it just SA?
Is the watch displaying the correct heart rate before you start?

Just some basic HR strap things you can try:

• try wetting the contacts / apply contact gel
• soft reboot the watch
• remove / replace HR sensor battery.
• re-pair the HR sensor
• Try another sport mode
• re-create your sport mode

[peringmar]

First, thank you for the suggestions, but I have already checked most boxes due to this being a repeated problem for me.

The watch shows the correct HR before start.

To clarify, it is the watch that shows the wrong data during activity.

[Dimitrios Kanellopoulos]

if its in the first minutes most probably its contact issue.

This is what I had observed.

Prestart -> all ok
First x minutes -> bad
PAusing helps. Perhaps the strap is not moving.

In regards to that, please try to use a non nylon / polyester t-shirt / top. Maybe that creates static

[peringmar]

@dimitrios-kanellopoulos
But what I find strange is that for this activity it did not find my correct heart rate for 6 minutes, but then a 2 second pause solved the problem.

That is why I usually do this 2 second pause right after starting (just forgot this time) because otherwise HR reading won’t work.

[Bradleyd]

@peringmar, I experienced this same funky low bpm count on a cycling commute yesterday using a Spartan Ultimate and a SmartHeart sensor. I’ve not seen this same low jump(s) using my regular commuting Ambit3 Sport watch with the same strap.

Looking at the below image from SA, the heart rate before 0:12 minutes is absolutely too low, the jump to 137 bpm is a good correction and happened when I stopped riding to fiddle with the watch and strap, the jump to +165 bpm is wrong before the 0:20 mark, the remainder of the rates are fairly accurate.

@surfboomerang , I don’t think this is an issue with wetting the strap or battery. The watch displayed roughly the same values I see in the SA time series.

Adding my experience, since I had the activity sitting open when reading this post.

[Mff73]

@bradleyd said in Suunto heart rate strap only works when pausing and un pausing the current activity:

Spartan Ultimate and a SmartHeart.

Is it the new Suunto Model this Spartan Ultimate?
And how do you feel with such a Smart Heart?
Hey, just kidding

[BrunoH]

@peringmar I’ve experienced something opposite of yours. In the beginning of an exercise my watch shows reasonable figures, but afterwards the Suunto App log looks like there’s double heart rate (way over 200 bpm) for a few minutes and then it finds the correct heart rate.

[Jannas10]

I’m having the exact same issue and with a Suunto 9 Baro, supposedly their flagship watch of a few years back. It’s not a heart rate strap issue. Before starting the activity the heart rate reading is accurate, the moment I start the activity the reading is 35% odd lower. The moment I pause the activity, the reading is accurate again.
Have you found a solution? It’s driving me mad. I feel let down by Suunto.