Heart rate: Charge 6 vs Chest heart rate sensor

[prenaud]

Hum, I thought the Charge 6 would give me an accurate heart rate. I just went from Charge 5 to 6 because I was too frustrated with the lack of accuracy. I did some spinning this am. It started well, but then things went weird towards the end. 😞

Chest HR

Charge 6

[Mcav75]

That comparison is not great. I do know that the Fitbit charge 6 is one of the more accurate wrist -based heart monitors, particularly at higher intensities. The YouTube channel, Quantified Scientist has a good review on this. 

My HR tracking experience with the Charge 6 is very similar to what is outlined in the review. It's therefore a concern that you'rs is not. My first thought is to make sure that the tracker is securely anchored to your wrist, and that it is on the "correct" wrist (as in, if you have the placement configured as non dominant on the app, make sure that's where it is). 

I'm getting consistent readings that very much reflect my workouts, and track very well with my dedicated HR monitor. I do hope yours gets sorted.

[prenaud]

Thanks for your reply. It's only my third day with the watch. I was very pleased yesterday when I did a 30 minute spinning session. It was really close to my chest sensor. It is definitely on the right wrist. Today's session was one hour. I wonder if sweat was a factor. I'll keep experimenting... 

[Mcav75]

That's really interesting to know, and it really shouldn't be getting dicey just due to a lengthy session. That said, you're the 2nd person who has reported a very similar issue, and they eventually got a replacement sent out.

Don't doubt yourself though. If you've done the basics, and it's not tracking right, get support of 8 it asap and make sure they get you on track (pun honestly unintended).

[prenaud]

Thanks again for the advice. I'm watching the video you mentioned right now. This is my 5th watch from 3 different companies and it is definitely the best results I've ever had. 

[prenaud]

A little update after 4 days with the charge 6.... For the last 3 spinning sessions, the watch gives readings totally off for the first 15 minutes (off by 30 to 50) compared to my chest sensor. After that, the watch is bang on. I've contacted Firbit 3 times and each time they make me try something different. I wonder what they have in their sleeves for when I have to contact them again tomorrow. Hahaha   

[Mcav75]

Hi Prenaud,

Just want to check something that may be a silly question, but it is worth asking anyway. Are you manually starting your exercises or are you letting it detect them automatically? If it is the former, then obviously something is amiss. If it is the latter, then you may find that it'll work better if you manually start the exercise. 

The reason I'm asking this is that 15 minutes is very specific, and the default time after which an activity gets automatically registered for most activities. I always start my activities manually because it appears to ramp up the HR tracking in some way.

[prenaud]

Thanks for asking. I do get it going manually. I learned about it when running. I couldn't figure out why it didn't match my friend's watch. It turned out I let the watch start the activity by itself. No more. 😁

[Triletics]

@prenaud Charge 6 happily locks to your cadence. It happens all the time to me, no solution.

Here's what it looks like to me:

Just 4 randomly picked runs (all HR above the Peak is wrong). Sometimes it stabilises, sometimes it doesn't. My cadence is between 195spm-200spm, and that is often read as HR by Charge 6. On an indoor bike that happens a lot less, usually, it locks onto cadence during off-seat intervals when a whole body moves up and down but it does happen.

[prenaud]

Weird. This is what my last sessions look like. It even went down to 60 today.

https://photos.app.goo.gl/XiRhQTFkjZiKCtp99

[Mcav75]

That looks very much like it going very wrong. I've attached a 15 minute HIIT for comparison. You can practically see my resting points in the graph.

I do hope you get your sorted. 

 

[prenaud]

Thanks for sharing. I contacted Fitbit via the chat help on 3 occasions and we tried something different each time. I was told to reply to the email this time instead if I still had issues. Even worse today. Still waiting for a reply.

[prenaud]

Another update... Finally, the reply came in and they asked me to reset my watch, which I had done 2 days prior. So, I decided to reach Fitbit by chat again. This time, the person said I would be getting an email from their "specialized team". Here are the questions they asked me:

*What were you doing when you noticed the problem? If you were exercising, specifically what types of exercise?
*Were you wearing the Fitbit device particularly tight or loose?
*What was the position of the Fitbit device on your wrist?

From my profile, I'm pretty sure they can tell that I know how to wear a Fitbit since I own one since 2019. What is weird is that even if the Charge 5 was not accurate, it was still better than my Charge 6.

https://photos.app.goo.gl/z1v4ei12DxUePLF58

[prenaud]

To be fair, I thought I should write a little update. After several chat sessions and email exchanges, I finally have another Charge 6 on its way. I should get it tomorrow. I thought it would never happen as I bought it second hand and I didn't have a receipt. I was able to give the location of where it was originally bought and that was enough for Fitbit to provide me with a replacement. 

[prenaud]

I give up. New Charge 6, same results...

https://photos.app.goo.gl/CYEYrW5djsdib9za8 

[RatherBeRiding]

I bought the Charge 6 three weeks ago. Can't get the Heart Rate to stay connected to Zwift app. Works at the start then drops after about a minute. Wore it and a Wahoo Chest Strap monitor while spinning. Charge 6 recorded 10 - 15 bpm under the Chest Strap the entire workout. Frustrating! 

[davipadd]

My experience is quite the opposite. When compared to my Polar 9 chest strap, the charge 6 tends to double my heart rate when resting. It is however more accurate when exercising, often within 5pm of the Polar device. The inaccuracy in resting rates causes other metrics to be quite meaningless.