Zwift Chat

[bridgy]

Well, I've just read that the following calculation can estimate your VO2 max as well:

Relative VO2Max = [(10.8 x W)/M] + 7
where:
W = watts (i.e FTP)
M = cyclist weight in kg
VO2Max = mL/(kg x min) (ACSM, 2010)

And guess what - feeding my FTP and weight into this calculation I get a figure of....48. This is identical to the Fitbit estimate which has only my HR data, age and weight to go on and knows nothing of my FTP. So that's pretty interesting and suggests it might be pretty accurate after all!

 

[CXRAndy]

VO2max = 15.3 x HRmax/HRrest

my example 15.3*181/54=51.28333333

 

[Randyberlin]

VO2max = 15.3 x HRmax/HRrest

my example 15.3*181/54=51.28333333

I like this formula! From my low FTP the other formula was depressing.

 

[CXRAndy]

I like this formula! From my low FTP the other formula was depressing.

Yeah Im the same, factor in weight and mine plummeted too

Which is probably more representative of actual performance

 

[<Tommy>]

I found this article and it seems their approach to research was pretty good. They conclude v02 estimates from computers and watches are pretty accurate. I’ll try and pay more attention to it in the future because up until now I just assumed it was a complete guesstimate.

https://sites.udel.edu/coe-engex/2019/03/16/how-accurate-is-your-garmins-vo2max-estimate/

On a side note power estimates from Strava etc are less accurate than bkool in my experience. With bkool you could probably say power estimates are generous by 10-30%. But with Strava the estimates can swing either side of reality and to a wider margin.

 

[theboxers]

Wow, unless you are about 18 years old that is amazing.

Froome is supposedly between 80 and 88.

My Garmin says I'm between 41 and 44 at the moment, which at 58 yrs old is good enough for me!

Maximal oxygen uptake norms for men (ml/kg/min)

rating	18-25	26-35	36-45	46-55	56-65	65+
	Age (years)
excellent	> 60	> 56	> 51	> 45	> 41	> 37
good	52-60	49-56	43-51	39-45	36-41	33-37
above average	47-51	43-48	39-42	36-38	32-35	29-32
average	42-46	40-42	35-38	32-35	30-31	26-28
below average	37-41	35-39	31-34	29-31	26-29	22-25
poor	30-36	30-34	26-30	25-28	22-25	20-21
very poor	< 30	< 30	< 26	< 25	< 22	< 20

Going by that chart and my Garmin FENIX 3 HR, I am above average with my current 38. I will take that being an overweight ex-smoker.

I am on the downward slope regarding weight again so I should be able to keep improving

 

[bridgy]

I found this article and it seems their approach to research was pretty good. They conclude v02 estimates from computers and watches are pretty accurate. I’ll try and pay more attention to it in the future because up until now I just assumed it was a complete guesstimate.

https://sites.udel.edu/coe-engex/2019/03/16/how-accurate-is-your-garmins-vo2max-estimate/

On a side note power estimates from Strava etc are less accurate than bkool in my experience. With bkool you could probably say power estimates are generous by 10-30%. But with Strava the estimates can swing either side of reality and to a wider margin.

Yeah I agree strava power estimates can be all over the place

 

[bridgy]

VO2max = 15.3 x HRmax/HRrest

my example 15.3*181/54=51.28333333

This one looks a bit generous - comes to 56.6 for me. Unfortunately I suspect the lower figure is nearer the truth!

 

[Norry1]

I can't believe my VO2 Max is higher than many of you guys - must be some glitch somewhere.

This is a shot of my Garmin. It shows 64 now but it was saying 68 a couple of weeks ago. I've just checked my weight on the Garmin and it was correct.

Any ideas?

 

[bridgy]

The new segment I set up is taking for ever too fully populate with past results and its been stuck at tne same figure all day so I am beginning to wonder if it will work at all. So we might have to bite the bullet and use the official segment - bit of a bummer for anyone like me who stopped after the meetup finish line as I'm not sure how much time was lost. Will have to warn people for Tuesday and Thursday rides to keep riding to the banner...

 

[<Tommy>]

I can't believe my VO2 Max is higher than many of you guys - must be some glitch somewhere.


View attachment 490967

This is a shot of my Garmin. It shows 64 now but it was saying 68 a couple of weeks ago. I've just checked my weight on the Garmin and it was correct.

Any ideas?

“1) The personal background info (at least age) is logged
2) The person starts to exercise with a device that measures heart rate and speed
3) The activity collected data is segmented to different heart rate ranges based off the persons background info and the reliability of different data segments is calculated(reliability is measured based off how continuous the activity is- uninterrupted segments are better than those where the user has to stop)
4) The most reliable data segments are used for estimating the person’s aerobic fitness level (VO2max) by utilizing the person’s heart rate and speed data“

I would suggest if you don’t use power but instead use speed then the data collected would be more accurate for runners rather than cyclists because there’s more chance of outside influences being exaggerated when cycling? For example If they are measuring your vo2 max from group rides or zwift rides I have a feeling it would skew results as perceived effort might be higher than actual effort.

But that’s not me dismissing your score. I’m obviously not qualified to say.

 

[Norry1]

I agree - if it uses speed for cyclists, that is bonkers.

 

[Whorty]

VO2max = 15.3 x HRmax/HRrest

my example 15.3*181/54=51.28333333

Using both methods mine comes out to 43.5 ... not great, but then I grind rather than spin so maybe not too surprising

 

[Whorty]

The new segment I set up is taking for ever too fully populate with past results and its been stuck at tne same figure all day so I am beginning to wonder if it will work at all. So we might have to bite the bullet and use the official segment - bit of a bummer for anyone like me who stopped after the meetup finish line as I'm not sure how much time was lost. Will have to warn people for Tuesday and Thursday rides to keep riding to the banner...

The end of the meetup to the Finish banner was close ... maybe 150-200 metres ... so 10-15 seconds maybe?

 

[Freelanderuk]

My garmin uses my power meter for VO2max
This is my latest reading