Accepted Solutions
@SunsetRunner -
There are two reasons for this -
First is that the heart rate zones formula has changed.
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.
Secondly, the move from Active Minutes to Active Zone Minutes has FitBit changing its definition of "activity".
- It used to be "Is your body active".
- It is now "Is your heart active and how active is it". You receive one AZM for each minute you average in the Fat Burn zone and two AZMs for each minute you average in Cardio or Peak.
For instance, you take a 30 minute walk without getting your heart rate up to at least Fat Burn.
- In the past you would be awarded 30 active minutes, or close to it. If you were burning more than approximately 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.
Hopefully the above helps - and welcome to the boards.
Best Answer@SunsetRunner -
There are two reasons for this -
First is that the heart rate zones formula has changed.
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.
Secondly, the move from Active Minutes to Active Zone Minutes has FitBit changing its definition of "activity".
- It used to be "Is your body active".
- It is now "Is your heart active and how active is it". You receive one AZM for each minute you average in the Fat Burn zone and two AZMs for each minute you average in Cardio or Peak.
For instance, you take a 30 minute walk without getting your heart rate up to at least Fat Burn.
- In the past you would be awarded 30 active minutes, or close to it. If you were burning more than approximately 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.
Hopefully the above helps - and welcome to the boards.
Best Answer