My max heart rate is 163, I'm 57.
non smoker
40lbs overweight
resting heart rate is 65 bpm.

Traditional calculations say 114 bpm is my 70% target heart rate.

"Karvonen" formula, the new gold standard, says 140 bpm for 70% which takes resting heart rate into consideration.

It does not take much of a pace walking to get to 126 bpm according to my Heart monitor and it's still easy to talk at 135 or more. I want to stay in the "fat burning" range to build a good fitness foundation before I push it to better aerobic condition.

Questions...
1. I want to burn fat, not glucose. Is 140 bpm too high a percentage to be walking at?
2. If I stick with a 114 bpm, I'll barely be moving. Should I slooooow down to this bpm pace?
3. Have you heard of the Karvonen formula and do you buy it?

Thanks,
Bill

I am not sure how useful those heart rate vs intensity measure. I always found those calculators to have very low heart rates.

When much younger, I could exceed 200 bpm for about 40-50 minutes ( HIIT training ), and had no side effects other than being tired. Even normal workouts exceeded what they considered OK. And my resting pulse was much lower ( about 60 ).

My gauge is the a measure of the ability to talk while exercising. A good vigorous intensity is to not to be able to speak more than a few word without getting out of breath. I would consider that my 75% level.

If you can carry on a conversion, you are not really working out. If you are not sweating, you are not exercising.