Fat burn now not 94

[Sam3star]

I’m really upset with the update and it’s made me want to change back to Apple. 
My calorie burn is high but my active looks horrible because even on a walk my heart rate is about 107 which is now classed as the “below zone” which is ridiculous!

why have they changed it from 94 to 114???

can this be changed back manually?

so angry.

[MrMarv]

@Sam3star -

FitBit has not given up the option to select between the Traditional Heart Rate Zones and Zones based on the relatively new Heart Rate Reserve formula.

The zones are commonly referred to on many web sites as "Training Zones", so that should tell you where FitBit is coming from. A FitBit Community Council member whose opinions and support in the boards I happen to admire, pointed me to a New York Times article regarding HRR. But everything in the article seemed to be about athletes in training, including an Olympic hopeful in canoeing, and not your regular John and Jane Doe.

The Heart Rate Zone calculations have moved from the Traditional formula which are straight fixed percentages (50, 70 and 85%) of your Max Heart Rate which is defined as subtracting your age from 220. For me, as a 68 year old male, my Max Heart Rate is 152. Traditional zone values for me are shown in the first data row below.

The new formula being used by many FitBit devices, including the Versa 2 as of the latest release, use a value called Heart Rate Reserve. Subtracting your resting heart rate from your max heart rate results in that reserve.

40% of the reserve is added to your resting heart rate to establish the beginning of the Fat Burn Zone.

60% of the reserve is added to your resting heart rate to establish the beginning of the Cardio Zone.

85% of the reserve is added to your resting heart rate to establish the beginning of the Peak Zone.

The new Heart Rate Reserve formula zones for me are shown in the second data row below. My fat burn zone starts 23 bpm above the traditional zone.

Actually, my Max Heart Rate is 120 (80% of traditional max) because I take Beta Blockers that throttle down my heart rate even during exercise. This was confirmed with my Cardiologist September 3rd during my semi-annual office visit and is discussed in the Harvard Medical School Harvard Health Letter from November of last year. My heart rate zones utilizing the Heart Rate Reserve formula and using my redefined Max Heart Rate is represented by the third data line below. Those zones match my Cardiologist's recommendation that I restrict myself to the high 90s and low 100s in my treadmill sessions, saying that was the best range for me and to not go above 110 for any sustained length of time

Even with the redefined Max HR my fat burn zone still starts 10 bpm above the traditional zone.

This leads to FitBit's redefinition of what determines "activity".

• It used to be "Is your body active".
• It is now "Is your heart active and how active is it".

For instance, you take a 30 minute walk without getting your heart rate up to at least Fat Burn, which, with me taking Beta Blockers is very easy to do.

• In the past you would be awarded 30 active minutes, or close to it if you were burning more than 3 times your resting calorie burn (BMR)  and you don't have to be in Fat Burn to do that.
• Now you will receive zero Active Zone Minutes because you were "below zone" for the whole walk.

Yow will receive one Active Zone Minute for each minute your average bpm is in the new Fat Burn zone and two minutes for each minute your average bpm is in either Cardio or Peak zones.

I hope this answers your questions and doesn't bring up too many more.

Good luck and welcome to the boards.