Some thoughts about Garmin/Firstbeat Training Load features

Since I started triathlon 5 years ago, I have always been fascinated by the training load concept. When I was a mere runner, mileage and duration were key metrics. With 2 new sports to take into account it was another game. I first fell in love with Training Peaks Performance Management Chart (PMC). It was so beautiful ! The more you rise the CTL line, the fitter you are ! (Really ?)

I really liked it but I was not using TP a lot so it was a lot of money for a mere chart. So I built my own stress score and used the TP principles to make my chart with a huge Google Spreadsheet I can play the whole day with.

Lately, I have figured out that aiming for a high CTL is a common triathlete error and when you’re self-coached it’s easy to fall in the trap of adding more and more volume. So I stopped filling spreadsheets and took a coach for better results (tl;dr : it worked very well !! but it was more expensive than a TP subscription lol)

Recently, I buyed a Garmin Edge 530 to replace my Edge 810. I had long waited for a new bike computer and I was rewarded for it since I found the new features and design very cool. With this new toy I discovered the new Firstbeat Training Load metrics and the siloed load (I’m a poet) in 3 categories : anaerobic, high aerobic and low aerobic. But since, I was mostly training with my Forerunner 935 which was laking these features I was wondering if True Up would do the job… So I have done several tests, taking screenshots of the Training Load on the Edge and see if it moved the needle after an activity with the Forerunner. It works ! For example, this morning, I went for a run with various intervals 5×2 min / 5×1 min / 5x30s with pace ramping up. I ended with an aerobic TE of 3,1 and an anaerobic TE of 2,3 on my Forerunner 935.

Here are the pictures of the Edge 530 before and after this run :

So you see a tiny change in the anaerobic and high aerobic loads. I have also noticed that small easy run, rides or swim do impact the global training load number, but not the details (I guess a light ride give you a load of 10 and this load is hidden in the sum of 4 weeks of training load). Notice that to have a training load with a swim you must have heart rate data. And I have read that the OHR while swimming while not super good does generate a training load.

Another common critic of the Firtsbeat/Garmin training load is the lack of parallel between what the watch says and what you’re doing. On this very blog, I have written that I am so pissed off after these metrics than I turn off the fitness notifications and that these were only marketing stuff to make ME by new watches. Fuck off ! (hint : I have bought a new watch). But lately I have been in the final phase of a race preparation with a strong build up and a tapering. I know it sounds crazy but the Firstbeat algorithm has nailed everything : all status productive, maintaining, unproductive, peaking, detraining have been paralled to what was happening !

The main caveat is the understanding (and translation) of unproductive. When you get unproductive I have figured out that you are on the edge. Either you’re gonna go through the training and grow. Or you might fall of the cliff and stress too much your body. To me « unproductive » is a warning sign, looking at other external and internal signals guide you toward keeping the same training load or taking it easy.

One another pitfall with True Up is not waiting enough for datas to go through the secret algorithm somewhere in the interwebs. One day I had a one point ramp up in VO2Max (which is evaluated too high by the way, I am sure of this) and the training load said : fitness down, load down. LOL. But a few hours later, the status changed to Maintening with fitness UP and load down. So be patient and be sure that both devices have synchronized with the servers.

Now, I am looking forward to see if things get really better about VO2max (I had troubles with running with a lot of elevation in the past) and Race time estimation with the Fenix 6. I will keep you posted.

update,

another example of true Up sync with same workout recorded on fenix 6S Pro and Edge 530 at the same time. The training laod was a tiny bit higher on the fenix 6S Pro but that not really significant, just a signature that the algorithm might be a little bit different between different generations of devices. I did a quite hard workout, with a focus on VO2max optimization and both devices gave a rise in the training load with two components : a rise in the high aerobic zone and a rise in the anaerobic zone. Frankly to me, it was more anaerobic than anything but it’s not complete non-sense either. The rise was in the same proportion on both devices.

Load Edge : 162, training load ramps up accordingly  : 1984, 412, 438 -> 1984, 501 (+89), 511 (+73) total +162

Load Fenix :172, training load ramps up accordingly : 1536, 408, 308 -> 1536, 496 (+88), 392 (+84) total +172

 

When you suppress an activity, the according training load stays in the global maths of the training load. In the Garmin Connect Mobile App, it’s a little bit more subtle, you keep the numbers in the training intensity graph, but you cannot see it in the exercice load graph.