Understanding the Cardio numbers on Fitbit HR

[catlover129]

After suffering a severe attack of angina last week, my doctor told me to get a Fitbit HR which I have done, and suggested walking at least 2 miles a day.  Since I have dogs and I walk already, the only major change I needed was to take the dogs on two extra walks each day which they love.  BUT my dashboard readings are showing I have x minutes in the red cardio zone which I know isn't accurate because I am walking at the same pace.  I have a high resting heart rate so I believe it registers in the cardio zone when I'm really doing nothing other than perhaps stressing over work or perhaps picking up my pace just a bit.  SO is there is any way for the device to truly distinguish between real exercise and a stressful afternoon?

[LZeeW]

@catlover129   First, make sure you are wearing your Inspire HR properly.  Not too loose and not too tight.  Second, Fitbit recommends wearing your Inspire HR farther away from the bony part of your wrist when exercising for better heart rate accuracy.  Finally, when you walk your dogs, is one leash in each hand?  Excess movement can interfere with heart rate tracking.  It's an engineering thing.  Can you manage both dogs in one hand?

Fitbit uses a commonly accepted formula for its heart rate zones.  It uses 220 - your age to calculate your maximum predicted heart rate.  Then the zones are certain percentages of your maximum predicted heart rate.  Some people say that this is good for a large number of average people, but might not be the best for an individual.  Some say that resting heart rate should be taken into account.  I think you should ask your doctor if there is a target heart rate that should be a limit, in addition to your distance goal.