Intensity Minutes

Intensity Minutes are not depending on the type of the activity. You just need to wear your watch, and have the wrist HRM on it active. If you use a HRM chest belt, it has to be connected to the watch (even if it is already connected to Edge). Edge does not process any Intensity Minutes, even with a HRM connected.

And then, one of the most important factors that can make a big difference from one day to another, is your avg. Resting Heart Rate on given day. In order to have the RHR properly logged, you have to wear the watch during rest (and/or during sleep), otherwise the RHR reading will be too high, and in the consequence the thresholds too elevated, and no or little IMs will be awarded.

My point was I did 90 minutes of activity and it only gave me 2 intensity minutes.  When I did this on my old 945, I'm pretty sure it credit me for the full 90.

oxymoronical said:

My point was I did 90 minutes of activity and it only gave me 2 intensity minutes

Yes, I know, and I wrote you what the reasons for it may be. Besides that, individual models may use different algorithm, and/or have different setting for the IM detection. Old devices did not have any settings for IMs, while newer devices let you chose between the default mechanism using the Resting HR, and the detection through HR Zones.

Got it.  Still not entirely understanding.  

I could (kind of) understand if based on my RHR around 45 (measured on my Fenix), a Z1 session around 110bpm may not have registered as any intensity (even though my chest HR linked to Zwift may have been at 120bpm)

But 

1.  I never think I had this issue on my 945.  

2.  Yesterday had at least 15 mins around 85% of max HR. If IMs are linked to wrist HR I'm sure it was up there too.  If not, I have a bigger issue with the wrist HR sensor itself.

3.  Other virtual rides looking with very similar metrics are recognized for their full duration as if the synch on the activity updated the IMs.

All that said, IMs are one of my least relevant metrics.  I was pointing out to any developers lurking that it's surely an issue if I do 90 minutes of aerobic activity but it only registers 2.

oxymoronical said:

All that said, IMs are one of my least relevant metrics.  I was pointing out to any developers lurking that it's surely an issue if I do 90 minutes of aerobic activity but it only registers 2.

More likely a problem with your settings or with the device configuration. Could you post a screenshot of the daily HR for that day? And another one of your Device Settings » Health & Wellness » Goals » Weekly Intensity Minutes? And also a link to the concerned activity? Is the Fenix 6 set as your preferred activity tracker?

Now I am understanding the issue.  The Fenix 7 is my preferred device but my wrist HR appears massively uderstated.

https://connect.garmin.com/modern/activity/8921359891

This first activity had my HR in the 160s and averaging 147.

https://connect.garmin.com/modern/activity/8921982605

It looks like my wrist based HR was massively understating the HR during the activities.  I didn't adjust my watch and the walk later in the afternoon looks fine.

This is concerning to me. Why is my watch showing a HR less than a 100 during an activity when a chest strap is showing more than 160bpm and an average of 147bpm?  This seems to be a reoccuring issue for me.  Is my HR sensor on my watch faulty?  My 945, 745 and 935 before that never had this issue.  They were typically close enough for me to not use a chest strap on most activities.  (My watch is not too loose and I have not adjusted it since these activities.

I typically don't even check my wrist based HR while I'm zwifting but I appear to have many activities not being captured for any intensity minutes which would suggest that this issue is ongoing.