Training Status - Unproductive

Status Unproductive should mean that your Fitness (VO2max) is decreasing even if your Load is increasing.

While trail running, did you use the Trail Run activity on your watch, or the normal Run activity?
The Run activity will update your VO2max value, while the Trail Run activity will not.
Using the normal Run activity for trail running could in other words cause a false decrease in Fitness (VO2max). Using the Trail Run activity will avoid this, but still add to your Training Load.

If you’ve had an active week of training then it is suggesting that perhaps ypu’ve done too much based on the pace and intensity of your trail run. Trail runs tend to have a higher heart rate for the pace compared to a similar road run.

There’s been heaps of discussion about whether or not to differentiate between Run and Trail Run as one adjusts VP2max and the other doesn’t. I can’t quite follow the argument that since Training Load is adjusted with Trail Run but VO2max is not, that somehow this will affect the training status. In this case the assumption being that had you set this run as Trail Run your training status would not have been ‘Unproductive’ but left unchanged after your last run.

FWIW, I leave mine on ‘Run’ all the time irrespective of whether trail or road. All activities contribute to VO2max.All activities contribute to training status. I don’t care too much about the training status notifications as long as I know that I feel ok. Sometimes too much information is too much!

Trail runs tend to have a higher heart rate for the pace compared to a similar road run.

This is actually the whole point of why you should use Trail Run instead of Run. Even if Garmin/FirstBeat claims that their algorithms give good estimates in real life scenarios by evaluating and leave out low quality, we know that to get good estimates it requires quite ideal conditions meaning flat roads, firm surface, no or low winds etc.

I can’t quite follow the argument that since Training Load is adjusted with Trail Run but VO2max is not, that somehow this will affect the training status. In this case the assumption being that had you set this run as Trail Run your training status would not have been ‘Unproductive’ but left unchanged after your last run.

It will affect training status in the sense that it would not let a false bad VO2max value distort the fitness component of Training Status.
Added Training Load could also change the Load component from decreasing or steady to increasing which again could change Training Status.

FWIW, I leave mine on ‘Run’ all the time irrespective of whether trail or road. All activities contribute to VO2max.All activities contribute to training status. I don’t care too much about the training status notifications as long as I know that I feel ok. Sometimes too much information is too much!

Okay sure, if you don't care about data quality or Training Status you are of course in your full right to do so, but the OP asked why his/her Training Status was acting like this and how to fix it, which makes me assume he/she is interested in good quality data.

I had another expression at the end here, but the moderator removed it, so let’s put it like this instead and I will leave it to you to figure out what the original expression was: «Poor data in, poor data out»

The Training Status widget is pretty useless for people who run hills regularly. My Vo2 max dropped two points because I ran a half marathon that included 1,300 ft of elevation gain. I would have selected Trail Run, but it wasn't a trail run...

Exactly. I've suggested to Garmin several times to please let the user decide by adding a toggle on/off option for VO2max and LT per activity type.
For instance, I would like the option to get my VO2max and LT estimates from treadmill running using a properly calibrated foot pod as source for pace/distance.
That way, I could do regularly runs on the treadmill under consistent conditions to track my fitness, while I could do my outdoor exercise without worrying about varying conditions distorting the physio recordings. (or at least I would be able to disable it on days/routes where I would know upfront that the results would be bad)

But at the end of the day it seems that Garmin clings to the idea that GPS is the best data source for speed, while they allow OHR for pulse source. Well, what about that. (I guess it's linked to their heritage as a GPS company...?)

Most of the problems occur because VO2max is being used as a daily training metric. It is not. It should never be. It is a measure that should only be assessed over a period of time. It only appears to fluctuate because of the numbers used in the calculation of the estimate. If you record all your activities as run, over time you will see the trend. It behoves us all to understand what the numbers mean. And that is not necessarily what some statement of 'unproductive' or otherwise suggests. If you have a properly prepared training program, you don't need Garmin to tell you whether or not you are training correctly. If you want accurate measurements of your physiology, you need to go to a lab.

Garmin devices can only provide suggestions. They should not be taken as gospel without some degree of assessment. They are a training aid.

It’s not garbage data. The FB algorithms are+/- 10% adrift from lab values. Using all the data irrespective of whether trail, or hills, or flats, or road, my V02max is not too different from lab values.

I would suggest that some people overthink things. Your VO2 is the result of all your training. It does not make sense to cherry pick the best values only.

Whatever floats your boat.

I follow your logic, but I don’t agree with it.
Let’s just leave it there and agree to disagree.

I usually get unproductive when i do a run at a leisurely pace. the FB algorithms don't seem to think recovery runs or what my training plans call general aerobic runs have any value.

according to Fb algorithms i should just do intervals all the time. according to them the aerobic training effect of a 5x1000m session is greater than that of a 34km run...