VO2Max isn't increasing

The zones will not impact vo2max.

Your max HR is.

Hello all,

I too have not seen much change in my VO2 Max since beginning to use the FR 955.  Having said that, my training has not been tailored with any objective in mind or dialed into any training program either, so I would not necessarily expect much of a change to my VO2 Max estimate.  

As I looked through examples of the last 20 runs for many of you (who have agreed to allow us consent to view your profile), I saw one of two scenarios.

1. The average heart rate and max heart rate for each of the last 20 activities trended to be too high with too much time in zones 4 and 5, making your watch think that you were working hard.  This would lead to no improvement in your Vo2 Max.  However, the max heart rate for these activities (likely) never exceeded the max heart rate in your user profile either, which, combined with the perceived heavy workload seen by your watch would have  led to a decrease in VO2 Max.  I say "likely" because I cannot see what the max HR is set to in your profile because of the real time settings feature present on the FR 955, but suspect that the max HR was not reached because there was no change in the thresholds of the HR zones in your profile.
2. The average heart rate and max heart rate for the last 20 activities was considerably lower than expected based on what the heart rate zones were set to, even while there were some speed/track workouts, which usually get a lot of zone 3 and zone 4 work, within those last 20 activities.  This makes the watch think that you have not been working hard enough to improve your VO2 max.  However, because of the frequency of the running activities in these lower heart rate zones (zones 1 & 2), there has been more than enough workload to maintain the current VO2 Max estimate.

I raised these concerns internally and have been asked to request the following, which I will be doing alongside all of you who choose to participate in this testing:

1. Set up a Hot Key on your watch to capture screenshots.
   • Capturing a Screenshot on a Garmin Watch
2. Reset your heart rate zones to default.
3. Reset your Max HR to default:
   • Males: 220 - your age
   • Females: 226 - your age
4. Verify that you have your HR zones set to % of Max or % of LTHR.
5. Confirm that you have enabled Auto Detect for Max HR and/or Lactate Threshold.
6. As you train, allow/accept any detections by the watch.  Take a screenshot of any notifications concerning new Max HR, Lactate Threshold, PRs, etc. 
   • These screenshots will have a timestamp on them so that we can correlate them to the applicable activity in your account.
7. Train normally for the next couple of weeks.

After a couple of weeks, please share your progress.

Personally, my vo2max has been fluctuating between 54-55 since I got the 955 1+ months ago.

When I do speed intervals, my vo2max will tend to go up. 

1 easiest way to verify if vo2max is working or not is to set the HR max much higher or much lower. This will trick Garmin into thinking that your body capacity has changed.

Kevin maybe if you are willing to sacrifice?

Well, I used the 955 for 3 months. It changed once when I started to use 3 months ago. But since then it has never changed. Despite holiday, less training, pick up again and train quit often and hard for a marathon. I don't know why this is happening, but before (945 etc.) it changed more often. So maybe it is better? Maybe not? Maybe it isn't working? I don't know. For the moment I don't use VO2max because I prefer training with power (Stryd). But I wanted to report here so Garmin can get into this. 

Garmin-Kevin Thanks for your dedicated effort to investigate this issue. To me it looks clear that the formula/algorithm/moving avarage behind VO2Max value has changed and incremental changes has been "scaled down" around 5 fold. 

In the sheet below I exported and cleaned my roughly 50 last runs on FR245 and the first 50 on FR955. As you can see on TE, Distance, Average Pace there's no huge differences and my training has been fairly consistent. Yet the average changes to VO2max was 5 times higher on the FR245. 

https://docs.google.com/spreadsheets/d/1u4m49UODB7dtvEFTUFNxgnqNMAHhYx_86NIu7NqEnQQ/edit?usp=sharing

In a building phase when I was ramping up volume it used to increase about 1 point per week, one time even two points in one hard interval session. I agree with scaling the changes down slightly but as it is now is to "insensitive" and likely don't reflect the current fitness. Since FR955 no change at all and training status has been on Maintaining almost exclusively which makes both metrics basically useless.

1.yes

2.yes

3.Thailand

1) So your data confirm vo2max change is less sensitive now.

2) Next question is the change for the good or better ? Less sensitive means vo2max will drop at a less rate.

3) I see your old and latest vo2max are similar. ie 50.72 and 50.81. Do you think your fitness has changed significantly then and now?

4) I think it is best to monitor the vo2max changes for someone who just joined Garmin and bought a 955. Preferably someone who started from a non running background. Then compare his/her vo2max progression as reported by Garmin and lab test result. See how the data correlate.

5) Lastly, aside from going to a lab, can always do a 1.5 mile run test. Has anyone compared? I know Garmin overestimated my vo2max in the past when I was using a 945. Now I feel my vo2max is more accurate.

1) Agree

2) Subjective, I would prefer closer to the FR245 where it's not static for months.

3) Just got a PR on 15k and 10miles on September 18 and I feel close to the same fitness as when I had 54-55 back in April.

Peter and li_who, I invite you both to follow steps in my recent comment and participate with me in the testing outlined there.

Kevin the MHR = 220 - Age is a very poor estimate of one's true MHR.

V02max will be grossly underestimated if true MHR is way higher.

I hope you will highlight this internally.

Maybe you can show the data from Peter. It's very clear that vo2max is less sensitive to change.

I do see a constant change in the VO2 max value (trending up), but auto max HR detection is off. In a avg 150ish run with a max HR of 171, the watch offered to replace my previous value 196 (value actually got with one prior session) with 191 (again, max HR 171:). I declined politely and turned max HR auto detect off!:)