How Edge calculate current heart zone decimal value

Hi all,

I don't understand how Garmin calculate current Heart Zone value in it's system default DataField.

I tried to develop the same "algorithm" based on my current Heart Zones but I can't get the same results...
See below an example:

Instant HR value is 62bpm.
The simple algorithm I've made gives me I am in Zone 0.7
Default device (I am using an Edge 840) calculation gives me Zone 0.5

My Heart Zones are the following:

Zone 0: 0 - 91
Zone 1: 92 - 109
Zone 2: 110 - 127
Zone 3: 128 - 145
Zone 4: 146 - 164
Zone 5: 165 - 183

Based on those values, my algorithm looks more precise... but I really do not understand how Garmin gives me 0.5 for the same bpm value (62).

Any idea?

Top Replies

FlowState 2 months ago +1

Hmm based on my testing and your numbers, it looks like Garmin has a hardcoded assumption that your HR cannot go below 30.

This fits with the values you see:

[instant_hr_in_zone_0 - zone_0_min] / [zone_0_max…
FlowState 2 months ago in reply to Simone85 +1

No problem!

Simone85 said:
Do you think this “min” value should be applied only for zone 0 calculation?

Or should it be applied for all the other zones?

Only for zone 0 calculations. You might need to select…

All Replies

0 FlowState 2 months ago in reply to flocsy🤠

Yeah that's what I figured. tbh I was just trolling haha.

Honestly I would say that it's a bug / design flaw in the language or compiler that replacing numeric literals with variables actually saves memory. (For years we've been forced to write bad code to save memory.)

To be fair, a lot of things have improved in CIQ / Monkey C.

0 flocsy🤠 2 months ago

Maybe it's too late, 'cause we already trolled this thread, but anyway let's continue here: https://forums.garmin.com/developer/connect-iq/f/discussion/406008/fractional-decimal-heart-rate-zone-calculation/