Fitness Age not counting vigorous days

Same for me , it is not recording days or the minutes correctly.    

I am going really mad with this topic.... However one thing I have to offer is that at least in my model, it's 5 minutes of continuous vigorous minutes that count as a vigorous day. So "just" having 5 minutes is not enough. Garmin does not tell us when a day is classed as vigourous or not so this is all messed up and intransparent.

This is still a problem on my Venu 3s.

It suddenly added to my fitness age and told me I needed to increase my fitness intensity days yet if I look up my 4 week intensity minutes, the days are clearly showing that I constantly exceed the required fitness days. 

How do you know which days are vigorous? My model does not show that.....

Look at your intensity minutes and go to 4 weeks. You will be able to see the days there.

I think you need to do a minimum of 15 intensity minutes a day for it to record as an intensity day.

I have to do 5 continuous vigorous minutes for the day to count as vigorous. But the vigorous days ar not shown anywhere. Talked to Garmin support about this - the app/watch does not show you which days are counted as vigorous which is very annoying....

Made a post about it and also suggested the feature....

forums.garmin.com/.../tracking-of-vigorous-days-not-transparent

mhgrove said:

When looking at my fitness age, I noticed it's recommending more vigorous days and tells me my 4 week average is only 1.6. I understand a "vigorous day" means I must have 5 minutes of vigorous intensity.

I went back and looked at each day individually, and for the last 4 weeks I have 3, 4, 3, and 3. So my 4 week average should be 3.25.

Anyone have this happen and successfully fix it?

I agree maths does not work here. I also made several checks and counted only those days whenI had definitely not just 5 vigorous minutes, but 5 CONTINUOUS vigorous minutes. Because it is the proper definition as said by other users, too!

Depending how you exactly calculate 4 weeks/28 days ( counting full days or also the the start/end times of the day are important) I had  8 or 9 vigorous days, while my 4 weeks avg is just 1.3. A long time ago ago it worked well, or even if it was not perfect the error was not so huge as it has been during the last 6 months. 

I also have a theory that there is a general fitness age bug, but when I reported that eg. my Enduro 2 never showed fitness age, just GCM, I was told that there was no general bug. Since then I reverted the sw version and  nothing changed.

I decided not to care about these data in GC/GCM at all. I do care about the total weekly IM which seems to be correct even in the long term? I never spotted any errors in 2024-2025.

Yes but the issue stands: why does Garmin not show the days that count as vigorous? It both does not tell you what counts as a vigorous minute nor when you have a vigorous day. I find that really dumb.

Some comments say that you need 5 CONTINOUS vigorous minutes for the day to qualify as vigorous.

This seems incorrect, the following official source says "at least 5 vigorous intensity minutes in a 30-minute time period":

https://www.garmin.com/en-US/garmin-technology/health-science/fitness-age/

However, with such a definition, it seems close to impossible to identify days that have been marked as vigorous... To be 100 per cent sure, you will need to perform either an

a)  activity not longer than 30 minutes with 5 of the minutes being vigorous, or

b) activity longer than 30 minutes with at least 1:5 ratio between vigorous and other minutes (in other words at least 16.7 % of total duration are vigorous minutes), otherwise not possible to be 100 per cent sure. A 60 minute activity with 9 vigorous minutes doesn't have be enough, since the 9 minutes may be evenly distributed over the 60 minute time period and no 30-minute contain the necessary 5 minutes.

It is time for Garmin to listen - and respond - to user requests and simplify reading of these data and most specifically ability to track vigorous days history.