All the info I read on the web says to use Heart Rate Zones as training guides, but I am finding them a bit misleading and confusing.
I am an averagely fit 52 year old. My resting Heart Rate is 55 according to Garmin, and my maximum Heart Rate is 168 (220 - age formula).
When I go for a brisk walk of 5km at 7kmph my average Heart Rate is 113bpm, 70% in Zone 2 and 25% in Zone 3. Seems about right, if a little low.
When I go for a 5km run averaging 11kmph my average Heart Rate is 155bpm, 72% in Zone 5 and 20% in Zone 4. With max HR of 174bpm!
According to the Heart Rate Zones, Zone 5 is 90% of my Max Heart rate and I am sustaining this for over 20mins, which should be impossible. 11kmph for 5km is not particularly fast.
Thinking the Garmin FR245 optical HR Sensor was not great I bought a GArmin Chest HR strap, but got the same results.
So I guess my real max heart rate is closer to 190. Putting this into the Garmin app, it recalculates my Heart Rate Zones. However this now means when I brisk walk at 7kmph at an average of 113bpm I hardly leave Zone 1 - which is Warm Up. I cannot walk any faster without running. I get no Intensity Minutes for a 7kmph walk, even if I walk 10km at this pace. And a slow stroll is Zone 0/Resting!
My feeling when walking tells me that a brisk walk feels like 65-70% effort, and running 80% effort, but this is not what my Heart Rate Zones is telling me. It feels to me that the Heart Rate Zones are not matching up with actual effort I am putting in depending on activity. Do I need to use a different formula/setting or something? Or is it possible to be fit for brisk walking but unfit for running?
