I have a FR 255 Music for about 2 months now (Firmware 12.27) and experience a severe problem with the VO2 Max calculation. I believe this is due to a bad algorithm and Garmin should take a look at this. Might be related to:
https://forums.garmin.com/sports-fitness/running-multisport/f/forerunner-955-series/304806/vo2max-isn-t-increasing
I am 26 years old, female, 1.83m, 66 kg and just started running again. About 4 weeks ago I started running again with the following results
- 20.10: 1.63 km @ 9:22 min/km @ 134 avg + 155 max HR (quite tired afterwards)
- 16.10: 0.88 km @ 5:40 min/km @133 avg + 174 max HR (benchmark run, all out and not able to walk afterwards)
- 3 max HR tests, all resulting in MHR = 185
As you can see, my VO2 Max propably should be below 30, but it started off with 46. I believe this was the last reading of my Vivomove HR from years ago and it was displayed eversince.
I logged 10 runs in the last 4 weeks with the recent 5 of them meeting the requirements for calculating VO2 max (>10 Minutes of constant running, outdoors + GPS, HR measured and HR > 70% of MHR). I greatly improved during this time, now I'm at:
- 05.11: 3.02 km @ 8:18 min/km @144 avg + 162 max HR (feeling good afterwards)
The watch and Garmin connect still display my VO2 Max at 46 with the graph at the watch showing that in decreased by ~ 0.6 in the last 4 weeks and it still decreases after every run. It even knows that it's way off and tells my by giving me a performance condition of -10 to -20 every time. This is really frustrating as most of the training features the watch might offer me are useless. My optimal window for acute load is barely reachable, my power condition is always very negative, my VO2 max readings don't display my progress and as a result my training status doesn't reflect that I'm improving. Seeing one's progress is like half the point of buying something that produces tons of metrics. Also the recommended trainings are not doable and the race predictions are useless.
I tried deleting my VO2 max from the user profile, turning True Physio off and on (and having a run in between) and researching the heck out of it. I finally found out that the VO2 max algorithm seems to be modified to only do very small steps with the recent *55-devices (see link above). But this is absolutely useless if it doesn't do big steps in the beginning (including recalculations after long breaks with no recorded data) to even out misreadings. Especially, if it (intentionally or by accident) uses years old values as baselines.
Maybe Garmin can take a look at this and fix the algorithm. My assumption is that it used the old value from my Vivomove HR and because it's so old, the algorithm immediately jumped out of its initial big-step-phase and only adjusts in tiny steps. If it even has a phase with bigger jumps to begin with (which it really should have!)
PS: This is runalyze's take on my VO2 Max:
Related complaints:
https://gadgetsandwearables.com/2022/08/16/garmin-forerunner-955-vo2max-222/
https://www.reddit.com/r/Garmin/comments/wpdzge/is_it_harder_to_increase_vo2max_number_on_955/
