How vo2 max relates to fitness

Luv2Run wrote:

Can you link to papers, texts, or anything else to support your claims?

This study is particularly fascinating for those who love the subject:

And they weren't athletes, but the oldies maintained cardiac output by an increase in stroke volume to offset the decrease in max heart rate.

Of course in accordance with the Fick equation VO2 max would be decreased.

it's genetic wrote:you and Coggan and many others are operating under the false belief that maximum stroke volume, maximum heart rate and maximum cardiac output are all happening at VO2 max.

Non-sequitur: the point is that training increases VO2max, sometimes considerably.

This disproves your claim that it is all genetic, regardless of the underlying mechanisms (i.e., which component(s) of the Fick equation show positive adaptations).

I want to be famous !

it's genetic wrote:

GJ1600 wrote:

I’ve always had this question about vo2 max, and my question is, if someone had a vo2 max of 75 and they had never trained for a 5k in their entire life. Then would they be able to run a fast time? Does vo2 max measure relative fitness, or just potential? Thanks in advance for the answers:)

You're getting the usual stupid answers here. VO2 max is genetic. It has nothing to do with 'aerobic fitness' just good health and having a fair proportion of slow twitch muslce fibers.

So the anwer is no, they will not automatically run a fast 5k without any training. They will run a slow time and be very sore for a week.

You failed to state: A XC skier who test 75 vo2max may race a 5K well. XC skiers with no running background are using many of the same muscles as runners but not in the same manner. Running is often a part of cross-training for XC skiers. A cyclist who test 75 vo2man may race okay at 5K but not great. A swimmer who test 75 vo2max with no running background will only be slighlty above the average man in 5K. Sixteen minutes to 17 minutes 5K.

Andrew Coggan wrote:

it's genetic wrote:you and Coggan and many others are operating under the false belief that maximum stroke volume, maximum heart rate and maximum cardiac output are all happening at VO2 max.

Non-sequitur: the point is that training increases VO2max, sometimes considerably.

This disproves your claim that it is all genetic, regardless of the underlying mechanisms (i.e., which component(s) of the Fick equation show positive adaptations).

That's not very scientific is it doc?

If you want to discuss the oxygen deliver part of the Fick equation, you might want to cosider that an increase in stroke volume, which as you rightly pointed out is correlated to increase in plasma volume also causes hemodilution.

This the assumption that an increase in stroke volume increases oxygen delivery is false becauase plasma carries only 3% of the oxygen and hemoglobin the other 97%.

You seem to be implying that we can increase maximal stroke volume without decreasing amaximal heart rate?

If that was true then we would be able to keep improving VO2 max as we get older.

You're getting your variables muddled. This is what I'm trying to telll you. And it's not a new concept that I have come up with either. It's been around longer than you have.

Yes, I failed to state in that post that some people with a 75 VO2 max are very good runners. I also failed to state that some people with a 75 VO2 max are exteremely good runners. And some are slow.

Because running is a very specific set of skills. But a high VO2 max or more specifically a high Cardiac Output is genetic.

Logic is the foundation of science.

Logically, if stroke volume increases with training, and maximal heart rate is unchanged, or decreases less in a relative sense than stroke volume increases, then maximal cardiac output must increase.

Logically, if the increase in maximal cardiac output is greater, in a relative sense, than any training-induced decrease in hematocrit, then convective O2 transport must increase.

Logically, if convective O2 transport increases, and O2 extraction either does not change or increases, then VO2max must increase.

Logically, aging has nothing to do with the question at hand, and is just a red herring offered to distract readers from your incorrect/illogical replies.

How? wrote:

I want to be famous !

Good luck with that. I suggest that you start by not wasting your and everyone else's time by posting anonymously to message boards such as this one.

Alternatively, if one prefers experimental data over logical reasoning:

https://www.ncbi.nlm.nih.gov/m/pubmed/1692570/

(TL,DR: Increasing plasma volume initially increases stroke volume, and hence cardiac output, more than it decreases hematocrit, resulting in an increase in convective O2 delivery and therefore in VO2max.)

Jon of course fails to realize that elite athletics involves getting all your numbers at the highest level before any one starts to suffer degradation. The ongoing struggle is to have all high points to coincide at the same point in time.

Athletes strive to have maximal stroke volume at the same time that they have maximum heart rate etc. coupled with artificially increased rate of capillarization due to training. They are not developing one only or waiting for age to enhance another.

Any sort of built in mechanisms that the body MAY have at later ages to preserve as much as possible is really irrelevant.

Jon Morange wrote:

Jon of course fails to realize that elite athletics involves getting all your numbers at the highest level before any one starts to suffer degradation. The ongoing struggle is to have all high points to coincide at the same point in time.

Athletes strive to have maximal stroke volume at the same time that they have maximum heart rate etc. coupled with artificially increased rate of capillarization due to training. They are not developing one only or waiting for age to enhance another.

Any sort of built in mechanisms that the body MAY have at later ages to preserve as much as possible is really irrelevant.

I think the point is VO2max is trainable, up to some genetic limit (which most never bump against).

The are many factors which make V02max trainable, one being Cardiac output, which also trainable.

This is true for everyone, to some significant degree, and how this varies between individuals or over time doesn't really change the above.

The training-induced increase in cardiac output as a key factor in Vo2Max increase has been established since the 1960s, here is a chart from the1968 Dallas bed rest study for instance (Saltin et al):

https://wol-prod-cdn.literatumonline.com/cms/attachment/156e1c1c-16cf-4d65-9d69-ff281cc6c2b2/sms12597-fig-0001-m.jpg

Even researchers such as late John Holloszy who paid more attention to the peripheral limitations acknowledged that increased Q explained a large portion of the Vo2max boost even when they found increased capillary density, mitochondria etc. also equally relevant.

It is another question how much increase in Vo2max or cardiac output can be expected if even a modestly trained athlete increases his or her training volume/intensity.

But those are assumptions. You are assuming that the training induced increase in stroke volume can be utilized with maximum heart rate. But your experience should tell you that max heart rate decreases with an increase in stroke volume.

Reading the abstract, there are plasma shifts implicit in the date presented. Can we discuss the issue of plasma shifts which occur during high intensity efforts?

One big problem in all of these tests and studies, how do you know you have tested VO2 max properly? How do you know what each subject's maximal heart rate is. Because that is what you have to test to be sure your measurement are accurate.

Do you not agree that max heart rate is variable? Joe Friel does and explains why. It's due to changes in plasma volume and yes stroke volume.

I'm bothered by the way many of you Exercise Physiologists are trying to sell a dream of improved Cardiac Output and absolute VO2 max. This is either delusional or disingenuous.

And btw I agree with the model for maximal oxygen uptake that predicts that it will be achieved slightly below maximal Cardiac Output, when max heart rate is achieved and stroke volume is sub maximal. And if you consider the variables, it is obvious why this is a more intelligent proposal.

We're bothered that an internet hack thinks he knows more than folks who actually studied at a school.

Not me - I'm entertained. :)

1. There is no assumption in the conclusion that endurance exercise training increases maximal cardiac output.

2. Plasma volume shifts with exercise (which do occur) are just another of your red herrings.

3. The way you know that VO2max has been tested "properly" is to get a PhD in exercise physiology, then apply what you have learned (including the standard criteria for establishment of VO2max).

4. The same is true for maximal heart rate (and since when in Joe Friel an expert in exercise physiology??).

5. To repeat: there is nothing "delusional or disingenuous" about stating that, in fact, endurance exercise training increases both maximal cardiac output and absolute VO2max (i.e., in L/min).

6. VO2max reflects the combination of SV, HR, and a-vO2 diff. It should therefore be obvious that there are multiple ways to achieve the same value.

it's genetic wrote:

Luv2Run wrote:

"Linked"????? It is one of the variables in Vo2max. Linked is like saying the pig is linked to making bacon. (I do not acknowledge the existence of turkey as a bacon source).

Cardiac output and VO2 max are not the same thing. That's what you seem to be missing.

Never said they were the same thing. Merely pointing out that cardiac output is one of the components of VO2max (along with a-VO2 difference).

Andrew Coggan wrote:

Not me - I'm entertained. :)

It was funny when Jon did this 18 years ago but now that he could have attained the necessary credentials and has not it's just sad.

Andrew Coggan wrote:

1. There is no assumption in the conclusion that endurance exercise training increases maximal cardiac output.

2. Plasma volume shifts with exercise (which do occur) are just another of your red herrings.

3. The way you know that VO2max has been tested "properly" is to get a PhD in exercise physiology, then apply what you have learned (including the standard criteria for establishment of VO2max).

4. The same is true for maximal heart rate (and since when in Joe Friel an expert in exercise physiology??).

5. To repeat: there is nothing "delusional or disingenuous" about stating that, in fact, endurance exercise training increases both maximal cardiac output and absolute VO2max (i.e., in L/min).

6. VO2max reflects the combination of SV, HR, and a-vO2 diff. It should therefore be obvious that there are multiple ways to achieve the same value.

1, You are making assumptions. Cardiac output has to be maintained in a healthy heart. Saying that maximal cardiac output can be increased with training is like saying that lung capacity can be increased with training. But lung capacity is easy to measure. How can you be sure you can measure maximal cardiac output correctly? How do you account for changes in peripheral resistance? Leave it to the Cardiologists to work out, it's their job and they are accountable for their actions. Coaching shouldn't involve such vague premises or promises. Maximal Cardiac Output is genetically determined and is maintained by good health. To state otherwise is a very contentious issue. Young people have higher absolute values for VO2 max and it declines with age despite increases in Stroke Volume. Do you deny this?

2, Plasma volume shifts are not a red herring, you're just prevaricating.

3, If you are measuring VO2 max, do you measure the sweat rate?

4, If you measure Maximal heart rate, do you take into account the fact that it has a seasonal variation of 8-10 bpm in some subjects as Joe Friel points out? And he even explains why, it's due to changes in plasma volume.

5, Exercise physiologists make many fantastic claims and many of these become 'conventional wisdom'. Is it unreasonable to suggest you don't do the same?

6, "VO2max reflects the combination of SV, HR, and a-vO2 diff. It should therefore be obvious that there are multiple ways to achieve the same value"

SV, HR and a-v02 are all variable. Be careful not to make too many assumptions about how you believe they can all be increased at the same time.

For example, does SV increase then plateau or increase steadily up to an observed VO2 max? And does an individual experience both these two traits in different conditions. For example, how does heat stress affect the test?