HRV biofeedback

[johdah]

I want to improve my health by doing HRV biodfeedback trainings to improve my RSA and strengthen my homeostasis. I have a Fitbit Sense which measure HRV during the night, but I wonder if there is any plans to provide continous feedback of the HRV curve which can be used to find my individual frequency and to do HRV training?
I'm considder purchasing separete HW for doing this, but for me it would be a much better solution if I could get it from my Sense that I already have,

As the sensor is already there, it is "only" software to deliver it to us customers.

[SunsetRunner]

The Sense is 2 years old art this point. I would not expect Fitbit to introduce any new features. Also, I question what the impact of that would be on battery life.

[johdah]

The function needs only to be active when you do coherence breathing and want to have real-time HRV feedback. 
I hope that they could improve Sense even if the model is two years old. Mine is only one years old. 

[t.parker]

@johdah we know there is something implemented that Fitbit calls HRV but there is no chance to verify whether it is accurate or not as it's hidden "behind curtain of the night" (I see pattern here with other features, too). What you want requires accuracy and you will do better if you go with EliteHRV and chest strap that detects R-R intervals. The app has HRV biofeedback feature and it's probably a gold standard of the HRV analysis (although, it's targeted mostly to athletes). Also, it isn't uncommon that there is a requirement of using a chest strap for HRV related functions (Garmin and Polar explicitly require chest strap for that reason).

[CrystalClearly]

Is there a Fitbit model that allows HRV-biofeedback (similar to Elite HRV)?

I was told that the Sense 2 and the Versa 4 do, but it would be good to hear from someone with experience before purchasing.