New Heartrate Sensor

[SunsetRunner]

Hi! Is there any information as to whether the Charge 6's new and improved heartrate sensor is better than the sensor in the Sense 2?

[LZeeW]

Hello @SunsetRunner and welcome to the Community.  Please check out The Quantified Scientist.  He puts many brands and models through identical workouts to report on accuracy.  He tests the optical heart rate monitor against a Polar chest strap.  He includes a graph of heart rate accuracy in every video I watched. He doesn't test side by side, so you need to search for a Charge 6 review and a Sense 2 review.

[dagterberg]

Hi, i’m not a 100% sure but to my knowledge the sensor is the same as the one in the charge 5. They only incorporated new algorithms that provide up to 60% improvement in heartrate accuracy. You could, like LZeeW mentioned, check out the Quantified Scientists review of the charge 6.

[Triletics]

@dagterberg I'm not familiar with Charge 5 but Charge 6 certainly does something better. However, it has its quirks, too. One of the issues I found is locking onto my running cadence. I run with 195spm+ and sometimes first couple of minutes Charge 6 shows my HR very high, like this today:

This was during my warmup when my HR wasn't higher than 140bpm. I pinpointed the exact place when Charge 6 locked onto my cadence. It was during running down the staircase (cadence 200+) and since then the value I was seeing most often where around my actual cadence. I think, most runners with a more casual cadence won't have this problem.

Here's a comparison with Garmin's chest strap:

The first 20 minutes were garbage due to cadence interference. This happened two times so far. You can see that the HR there is hovering at the same number as my steps per minute. Not sure why this happens but then it stabilized and the remaining workout matches chest strap readings really well. Also, the first interval is slightly wrong. Still, among all Fitbits I think this Charge 6 is the most accurate one. I have never had results like that on Sense or Sense 2 (well, sometimes, it was a lottery). You can also see that the orange Charge 6 line is smoother. I believe Fitbit applies some data smoothing/error correction algorithms on Charge 6.

[Markrrrrr]

I can't answer your question but I was hoping the heart rate monitor would be more reliable than the Charge 5 but I'm afraid it's actually worse!

As an example, my heart rate gets up to about 135 doing weighted squats but the Charge 6 hovers around 77 and consequently my weight training workouts are showing as zero zone minutes.

So far not at all happy

Cheers, Mark