Endurance Score Meaning

some beautiful Garmin brand numbers

It is just a marketing thing.

To justify an ugrade to the latest watch.

definitely isn’t a marketing gimmick, it works but you weren’t supposed to live by the feature. it’s just a guide.

I think that both endurance and hill scores are mainly useful for longer term trends, and if you change your training and want to see its effects. If you already know that you have good endurance and know how to train for it, you don't need a watch to tell you anything.

GarminMarathoner said:

what is this really supposed to mean in terms of anything?

In the context of your current VO2 Max estimates and training history, the watch is telling you have done an excellent job maximizing the utilization of your aerobic capacity.

The endurance score is an attempt to describe your endurance capability in the context of your VO2Max, age, etc. 

In the past, users only had the VO2 Max number as a gauge of performance capacity. But this capacity can plateau, while performance at endurance races can continue to improve as athletes perfect their abiliy to maximize the utilization of the aerobic capacity.

As explained in the following support article, the watch uses your training data over different period of times to evaluate this score.

www.garmin.com/.../

How could the endurace score be biased, if it is?

Since the endurance score is cross-activity, there could be a case where very long bike rides would be boosting the endurance score (I guess this is not your case).

Since your race prediction is a bit on the lower side, there is a risk that your VO2 Max is underestimated and/or your training data doesn't reflect your performance capability best. It is a risk, not a certainty. For example, if your metrics are a bit off, your training focus balance might be biased towards low to threshold intensities. The lack of maximal efforts could throw some additional bias in the results.

This is an excellent reply, well said.

One aspect of your last paragraph that I'll add on though:  Vo2Max can be overestimated or underestimated simply by inputting the wrong HR Max.  Too high and the watch will overestimate Vo2Max - too low and the opposite happens.  Not sure if this is the case with the OP but it's one factor that alot of users overlook.

GarminMarathoner said:

As of V16.17 I now have an endurance score, and it's something absurd sounding ~ 9800

I forgot to add that my endurance score started with the Elite status and has been getting lower. I am now at the top of the blue range and it seems to have stabilized. What happened that could explain the decrease?

- during the summer, I dropped biking. No more 3h+ long rides,

- simultanously, I focused running on 5k training plan. The longest easy runs were about an hour and change.

- running VO2 Max decreased slightly by a point while I was running in the 90F range. Probably heat acclimation. Bking VO2 Max didn't change.

I am now going back to running and biking. So, I will watch the endurance score as I pick up biking. On the running side, I am training for another 10k so I don't know whether the difference in training patterns vs. a 5K will impact the score. Temperatures have been cooler now, and the VO2 Max for running is slowly creeping back up.

Thanks. There's a good chance my VO2 max is understated, though its at 65.  I've seen a high of 69 a few year back on a previous garmin though I'd suggest I'm not quite as fast these days.  

I'm in a big marathon block (the 100+ weeks) and the watch doesn't respond to say a "short" session at i-pace. I would have thought the 5k predictor would be influenced but nope. HR was above threshold etc.  It was a 16:50 5k effort so it was fairy close to max effort esp with current training, but I got a stronger input from a long run at easy pace (a marathon distance at 4:05/k pace) where the predictor dropped from 17:33 to 17:15 but subsequently went up to mid 17s (like when I did that 5k...).

I've kind of give up on trying to convince garmin what a max effort is.