Problem with Vo2max calculation

Hi, I am using the Fenix 5X since beginning of this year. In this period I did 12 outdoor runs both with wrist pulse and heart rate monitor. The device is not calculating VO2 max values and no fitness status is shown. It says: use device one week and run min. 10 minutes outside. Both is overachieved, yet no VO2max value. By that occasion I realized that the device is not storing the rest pulse values. Whenever I enter it (both manually and by average measurements) the field is empty, the next time I check. Might that be a reason? As side information: I am not using different sport heart rate zones. Is there any idea, why VO2 max (and fitness status) is not working? Thanks!

GS

0 RemiM over 7 years ago

Are you using the trail running app ?

0 mcalista over 7 years ago

Try entering your resting heart rate in Garmin Connect (web or mobile), then doing a sync.
As above, it needs to be with the Run app, not the Trail Run app.
Also, make sure the Performance Notifications in the Physiological Metrics are on.

0 Former Member over 7 years ago

Try entering your resting heart rate in Garmin Connect (web or mobile), then doing a sync.
As above, it needs to be with the Run app, not the Trail Run app.
Also, make sure the Performance Notifications in the Physiological Metrics are on.

Damnit, that makes a lot of sense, I've been having same issue. I only use TRAIL RUN applet too.

Please don't tell me it's the same thing with VO2 Cycling with BIKE and MTB as I've also been doing that...

0 Gabriel_Seiberth over 7 years ago

Great, thanks to both of you! I actually use Trail Run App, yes. Do you happen to know, why that restriction is the case? I will also try to sync rest heart rate, but anyway it would be good if that issue would be fixed (if Garmin is reading). Thank you!!

0 razmichael over 7 years ago

This was implemented pre 5 series (in the 3) after many of us asking for it (maybe not implemented in this specific way but...). The Firstbeat algorithm is based, in part, on HR vs pace (more to it obviously). So high HR with slow pace meant the same whether it was because you had a low VO2Max or were running in mud, sand, tricky trails etc. Also, as I mostly SnowShoe run in winter, I would see my VO2Max drop way down each winter. When I cared what my VO2Max was being reported as, I would not use a HR monitor for trail runs. Easier now as you just select run or trail run (or duplicate Trail Run for a Snowshoe app) and no impact on VO2Max. In the end, the accuracy for the VO2Max estimate will vary greatly for different people. I will however say that last year my treadmill lab tested value was almost exactly the same as the Firstbeat/Garmin estimate.

0 Gabriel_Seiberth over 7 years ago

This was implemented pre 5 series (in the 3) after many of us asking for it (maybe not implemented in this specific way but...). The Firstbeat algorithm is based, in part, on HR vs pace (more to it obviously). So high HR with slow pace meant the same whether it was because you had a low VO2Max or were running in mud, sand, tricky trails etc. Also, as I mostly SnowShoe run in winter, I would see my VO2Max drop way down each winter. When I cared what my VO2Max was being reported as, I would not use a HR monitor for trail runs. Easier now as you just select run or trail run (or duplicate Trail Run for a Snowshoe app) and no impact on VO2Max. In the end, the accuracy for the VO2Max estimate will vary greatly for different people. I will however say that last year my treadmill lab tested value was almost exactly the same as the Firstbeat/Garmin estimate.

Hi razmichael, thanks for this explanation. So the idea behind the restriction is to make sure that the measurement conditions are as fair as possible. Makes sense.

0 tmk2 over 7 years ago

I actually use Trail Run App, yes. Do you happen to know, why that restriction is the case?

To put simply, because terrain slows you down in an unpredictable way and it is difficult for the algorithm to realistically gauge your effort against your pace.

0 Former Member over 7 years ago

This was implemented pre 5 series (in the 3) after many of us asking for it (maybe not implemented in this specific way but...). The Firstbeat algorithm is based, in part, on HR vs pace (more to it obviously). So high HR with slow pace meant the same whether it was because you had a low VO2Max or were running in mud, sand, tricky trails etc. Also, as I mostly SnowShoe run in winter, I would see my VO2Max drop way down each winter. When I cared what my VO2Max was being reported as, I would not use a HR monitor for trail runs. Easier now as you just select run or trail run (or duplicate Trail Run for a Snowshoe app) and no impact on VO2Max. In the end, the accuracy for the VO2Max estimate will vary greatly for different people. I will however say that last year my treadmill lab tested value was almost exactly the same as the Firstbeat/Garmin estimate.

THANK YOU FOR THIS EXPLANATION. I was frustrated but didn't have time to debug fully.