Lactate threshold activities

The latest software has this new feature:

  • Lactate Threshold estimates are applied automatically after training with heart rate.

But what are the requirements to get a new lactate threshold estimate? The Garmin documentation still mentions guided running exercises, but that is now removed on our watches.

I have gotten the impression that we can now get estimates by using the wrist heart rate sensor, and from activities that are not necessarily done at very high intensity, but which activity types are eligible? 

My last estimate was from a guided outdoor run in august 2023. It would be nice to have a new estimate, more in line with my current shape.