What's wrong with Garmin? how to make 'High Aerobic' load?

My zones are based on LTHR.

I have a similiar issue here (but at least I get some high aerobic points) and try to understand it:

Today I tried to get some high aerobic load in my training and used my powerzones for that --> I spend over an hour in Zone 3-5 which is, according as I know "High Aerobic". That is even the case when I crosscheck it with the Firstbeat Homepage.

Is maybe Garmin only using the Heartrate Data to calculate the training load? I thought Garmin uses the PowerMeter for that when cycling - which would be much more accurate espiacally regarding anaerobic loads. 

So my questions are:

1. Is Garmin using the powermeter data or heartrate data regarding training focus?

2. What are the exact zones for high aerobic training load?

Greetings from Stuttgart, Germany and thanks for your help

Tim

i think the problem is like it was described before. TL points go to ONLY ONE bucket (Ana, high aero, low aero). so if you have a bit more (dominant) time in lower zones (<=Z3), doesn't matter if you did intense workout in Z4-Z5, it'll be assigned to 'Base' category (hence low aerobic points) :/   i'll try to confirm that on my next ride. i'll record my ride as usual (with >1h ride with low intensity thru a city), and shorter part (only climbs - more intense) and we'll see.

Interesting! 

I will try the same thing too and then we can compare the data. 

Would be rubbish of course - normally I do a warm up and a long cool down - which of course normally is around Z1

Ok I tried it today - I did some Sweetspot Intervalls today which in my opinion should be High Aerobic - but also a lot of recovery as you can see in the Powerzones:

. 

This is the training focus before the ride:

And after the ride:

As you can see there is an expected increase in the low aerobic load and a bit of anaerobic load (I pushed a little on some Strava segments ;) ). 

But there is no increase in the high aerobic load. The question is why - I have actually no idea how to target especially the high aerobic load.

I made a request to the Garmin support team about this and will text you as soon as I get an answer

The algorithm is a propriety Firstbeat algorithm so I doubt Garmin will tell you how it works.

This is what Firstbeat say about it: https://www.firstbeatanalytics.com/en/features/training-load-balance/

You will probably need enough zone 4 HR to really persuade it you are doing high aerobic stuff and probably appropriate power zone times as well.

Most of the power levels in your charts are low.  Maybe you need more higher power zone times - zones 3 and 4?

Double check you zones are set appropriately.  Changing the zone boundaries does affect this.

You probably need more rides at appropriate levels to make the load focus bars change a reasonable amount too.

I had 40minutes in the Powerzones 3&4 and 34minutes in HR Zone 4. Shouldn't this give at least some pointes in the high aerobic section?

I don't know.  Maybe more is needed to make the bar move enough to be noticeable?  When I had my zones set incorrectly it took a good few rides for things to even out after I corrected my zones.

Remember the bar chart is is using data from the last 4 weeks.  34 minutes probably isn't much time compared to how much you rode in the past 4 weeks.

Just from looking at the shape of those graphs, there seems to be a mismatch between your HR zones and your power zones. The algorithm uses power if it is available, and only HR if power is not available.

Aerobic and Anaerobic is what I would expect from that power distribution - you're just not spending much time in z4 and z5 power zones for it to be high aerobic.

Below is a ride I did yesterday 4x10 minute sweet spot intervals. Categorized as High Aerobic. (Sorry, I didn't get before and after shots of Load Focus).