Inspire 3 active minutes heart rate zones incorrect

[EEM23]

Inspire 3 Active Minutes “your Heart Rate Zones” is incorrect. 

Fitbit’s documentation has the following four formulas for determining heart rate zones. 

max rate = (220 - age) x .5

Fat burn is between max rate x .5 and max rate x .69

Cardio is between max rate x .7 and max rate x .84

Peak is max rate x .85 and above

“My” rates in the app are

Fat burn one hundred to one hundred fifteen

Cardio one hundred sixteen to one hundred thirty five

Peak one hundred thirty six and above

These are the correct rates for a 20 year old, I’m not 20. 

Using a custom max rate does NOT fix the problem, it changes some numbers, but the rates are all incorrect. 

Has any one found a solution for this problem?  Does it affect all ages or is it limited to a subset of ages?  

[LZeeW]

Hello @EEM23 and welcome to the Community.  The Inspire 3 awards active zone minutes, not active minutes.  Active zone minutes use a different equation that uses your resting heart rate in the calculation.  I believe that same Help article you are using describes the method for calculating active zone minutes.

Active minutes are an outdated measurement of physical activity.  Active zone minutes are consistent with CDC and WHO guidelines for activity.

[EEM23]

LZeeW - Thank you!!!  I tried to get an answer from the ChatBots and that was an exercise in futility. With you guidance, I found this interview with Megan Ritter-Lluncor of Fitbit https://www.wareable.com/fitbit/active-zone-minutes-explained-7968    (pertinent part quoted below)

Thank you again, EEM23 

“Many people will see that they’re not getting the same credit of Active Zone Minutes than they did for the simple Active Minutes metric. But that doesn’t necessarily mean that AZM are harder to achieve.

That’s because of how AZM is worked out.

AZM is time spent in each heart rate zone, but those are not set the same for everyone. Fitbit uses the Karvonen calculation of 220 minus your age to work out HR Max.

They then calculate HR Max minus resting heart rate to figure out your heart rate reserve.

“We use that heart rate reserve to kind of see how much you need to get your heart rate up to be in certain zones. So then what will be is your resting heart rate plus 40% times the heart rate reserve that's to get into fat burn. Cardio is 60% and peak is 85%,” Ritter-Lluncor explained.

So why does that matter? Well, because your heart rate zones are calculated in this way, as you get fitter, you’ll find you will need to do more to trigger Active Zone Minutes.

“For some people whose resting heart rate is a little higher, they may see very similar levels active minutes and active zone minutes. It totally just depends on the user,” Megan said.”

[LZeeW · Accepted solution]

I’m very happy that I could help.  The CDC and WHO recommend a combination of moderate and vigorous intensity activity.  The CDC updated heart rate zones don’t take your resting heart rate into consideration.  I prefer Fitbit’s heart rate method.