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Wiggins' blood values

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Sep 2, 2012
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taiwan said:
How accurate does it need to be? There's still a positive relationship between body mass, bv and power.

Can the same equation be simply applied to the same individual at varying weights, or given the specifity of the target weight loss how would this skew the calculation?

I think Wiggo is saying that it isn't possible to maintain absolute power levels and yet to reduce body weight to the degree Wiggins has done. This is because of the relationship between power and blood volume. (sorry if I got this wrong) This makes perfect sense.

However, whether or not the relationship remains positive, if the means of calculating, and applying this same calculation to the same individual of varying weights is grossly inaccurate - it may give a misleading impression
 
Sep 29, 2012
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Don Quixote said:
Can the same equation be simply applied to the same individual at varying weights, or given the specifity of the target weight loss how would this skew the calculation?

I think Wiggo is saying that it isn't possible to maintain absolute power levels and yet to reduce body weight to the degree Wiggins has done. This is because of the relationship between power and blood volume. (sorry if I got this wrong) This makes perfect sense.

However, whether or not the relationship remains positive, if the means of calculating, and applying this same calculation to the same individual of varying weights is grossly inaccurate - it may give a misleading impression

Not sure. Nothing is turning up on searches. If anyone finds anything specifically related to accuracy of Nadler's equation with respect to athletes, I'd appreciate seeing it.
 
Sep 2, 2012
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Dear Wiggo said:
I went looking for that - and for kids it's not too accurate as is, but for adults it's apparently pretty safe. Not sure on trained athletes.

The study I linked shows remarkably higher blood volume than what I have calculated, no doubt due in part to plasma expansion (up to 1l during the Tour de France is mentioned), but as the next post points out: the relationship is not in dispute, and should be consistent enough between pre and post-weight loss that the accuracy I have used provides an example of the effect, even if it is actually different for an individual.

It's not 100% clear but in my assumptions I write,

although I have used 14g/dL for the calculations and an unmodified Nadler formulae for TBV, the natural values of these 2 variables would seem to be consistent for the rider, and decrease with weight loss. Whether their stable Hgb is 12 or 16 - it would return to that value. Whether their TBV follows Nadler's or not, their height will not change, and their blood volume definitely will due to weight loss - that phenomenon is not in dispute.

I should separate them out to make it clearer.

Thanks. I can't find any relevant studies re effects of weight loss on blood volume for trained athletes. Which is a bit surprising given its particular relevance to cycling - will keep looking tho!
 
Jul 10, 2009
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Don Quixote said:
Can the same equation be simply applied to the same individual at varying weights, or given the specifity of the target weight loss how would this skew the calculation?

This is obivously very important question. I would assume at least the first studies behind formulating the equation have been cross sectional.

Anyway thanks a lot for 'Dear Wiggo' to come up with this! I have several times asked an honest question (since I am also just another bloke who rides his bike without special insight excluding a handlful of elementary physiology textbooks and articles available online, so it's all very interesting) about weight loss vs. power loss in a hope that someone would come up with a plausible explanation and even I cannot be 100% sure if this is it, it is at least a very sound trial.

For oxygen consumption vs. weigth loss referred earlier, I think the consencus is that the rate limiting step is on the supply, not demand side (see eg. Limiting factors for maximum oxygen update and determinants of endurance performance, Basset et al.), body uses all available oxygen as long as certain amount of body's muscle mass is used and it has been repeatedly shown in studies that trained cyclists at least reach or exceed their VO2Max achieved in treadmill.
Add to that the very, very low force requirements of (endurance) cycling, I have always wondered what could cause the power loss related to muscle mass loss.
 
Sep 29, 2012
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_frost said:
This is obivously very important question. I would assume at least the first studies behind formulating the equation have been cross sectional.

Anyway thanks a lot for 'Dear Wiggo' to come up with this! I have several times asked an honest question (since I am also just another bloke who rides his bike without special insight excluding a handlful of elementary physiology textbooks and articles available online, so it's all very interesting) about weight loss vs. power loss in a hope that someone would come up with a plausible explanation and even I cannot be 100% sure if this is it, it is at least a very sound trial.

For oxygen consumption vs. weigth loss referred earlier, I think the consencus is that the rate limiting step is on the supply, not demand side (see eg. Limiting factors for maximum oxygen update and determinants of endurance performance, Basset et al.), body uses all available oxygen as long as certain amount of body's muscle mass is used and it has been repeatedly shown in studies that trained cyclists at least reach or exceed their VO2Max achieved in treadmill.
Add to that the very, very low force requirements of (endurance) cycling, I have always wondered what could cause the power loss related to muscle mass loss.

No worries, Krebs Cycle.
 
Jul 10, 2009
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Dear Wiggo said:

I am not, I have never met and I have absolutely no connection to Krebs Cycle. If I have understood it correctly he is from Australia which could not be very much further from me. I am from Finland as my forum profile says.

I don't have any particular reason to hide my identity but it would tell you absolutely nothing because I am really a nobody, just another bloke who rides his bike.
 
Dear Wiggo, I think the use of your data as a proxy for performance is incorrect. Numbers and data is valuable and interesting, but doesn't paint an accurate picture of performance. You look to VO2max data often, but I don't think it is valuable when evaluating performance in stage racing, or hour long TTs; the intensity just isn't that high. Similarly, Wiggans's TT is not only determined by absolute power. His technique is probably maxed out and has been for years, but any training adaptations over the last 3-5 years will have prepared him to recover within a GT, and dose out more effort in late stages. The psychological boost of fighting for yellow is often cited anecdotally, but there is research backing the benefit of the right psychological context for peak performance.

Fitness his hard to quantify exactly. Performance is even more difficult.

Looking purely at your numbers, I can see what can be interpreted as not right. But you're missing the forest for the trees when you isolate variables


Brad certainly climbed better than he ever has at this Tour, thanks to the improved P:W. Unfortunately, Brad's complete and utter drubbing of everyone in the 2012 Tour de France long TTs & Olympic Games TT would seem to indicate there was not the expected 7% decrease in power.

In fact, given he was at the head of the race, we would expect his performance against other riders to at best remain static, or slightly diminsh, thanks to the wonders of plasma expansion. Instead, we see his TT performances do this:

Stage 9: Chris Froome needs 3% more power to match Wiggins
Stage 19: Chris Froome needs 6% more power to match Wiggins

Stage 9: 10th place needs 13% more power to match Wiggins
Stage 19: 10th place needs 15% more power to match Wiggins

Conclusion: Something isn't right.

Not to sound like a broken record, but performance is not determined by any single variable
 
Sep 29, 2012
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More Strides than Rides said:
Dear Wiggo, I think the use of your data as a proxy for performance is incorrect.

Could you write this in another way? I do not understand what you are saying.


More Strides than Rides said:
Numbers and data is valuable and interesting, but doesn't paint an accurate picture of performance. You look to VO2max data often, but I don't think it is valuable when evaluating performance in stage racing, or hour long TTs; the intensity just isn't that high.

FTP is critical in these TTs and stage races. FTP is a % of VO2max. VO2max is the limit of an athlete's performance. The study cited (I am guessing you did not read it to disagree so freely) says exactly that - "VO2max, in a way, represents endurance performance". You are not disagreeing with me, you are disagreeing with PhD authors of a study.

More Strides than Rides said:
Similarly, Wiggans's TT is not only determined by absolute power. His technique is probably maxed out and has been for years, but any training adaptations over the last 3-5 years will have prepared him to recover within a GT, and dose out more effort in late stages.

Do you recall 2011 WC TT vs 2012 Olympic TT? Brad tells us himself that he is going to win all the TTs in 2012 because of the gears and the rolling resistance and going further because of a bigger gear for the same power and the respiration.

More Strides than Rides said:
The psychological boost of fighting for yellow is often cited anecdotally, but there is research backing the benefit of the right psychological context for peak performance.

Fitness his hard to quantify exactly. Performance is even more difficult.

PhD authors disagree.

More Strides than Rides said:
Looking purely at your numbers, I can see what can be interpreted as not right. But you're missing the forest for the trees when you isolate variables

Perhaps you can explain why Cancellara does not lose 5kg and join Bradley in yellow at the end of the Tour, given he has always beaten Brad in TTs.

More Strides than Rides said:
Not to sound like a broken record, but performance is not determined by any single variable

VO2max is a complex system of many variables, not a single variable. It is even described above as the sum of 2 items (oxygen delivery and oxygen consumption) and some of the variables affecting those (thermoregulation, plasma volume, total hemaglobin mass, etc) are also discussed.

I would be very interested to know why acoggan felt losing weight was detrimental to TT performance back in 1999:

http://www.trainingandracingwithapowermeter.com/2011/08/top-10-things-ive-learned-using-power.html

I just stumbled upon this Lettermanesque top 10 list that I first posted to the web in 1999 (after my 1st season using a PowerTap):

Top 10 things I’ve learned using a power meter
10) I shouldn’t lose weight
9) I need big gears
8) I need small gears
7) Strength is irrelevant
6) Don’t start too hard in TTs
5) Train less, rest more
4) Heat acclimatization is critical
3) Specificity
2) SPECIFICITY
1) SPECIFICITY!

Interestingly, even after all this time I'm not sure I would change anything on the list (except perhaps the "train less, rest more" conclusion, as I don't train or, especially, race as much as I used to).
 
Sep 29, 2012
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It's rough, but this is attacking the puzzle from the other side of the coin...

bloodvolume200420092011.png


Input regarding expected % of VO2max sustainable for the durations listed welcome.
 
Sep 29, 2012
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Fidolix said:
"I am really a nobody, just another bloke who rides his bike."

Really?

It's Krebs Cycle. He rides a bike too.

18 minutes before that post, he's writing

_frost said:
Perhaps I should have been more explicit saying that I have seen 85-90% of VO2Max quoted as the maximum level that can be sustained and knowing that due to VO2 drift the VO2 in later stages of prolonged effort is lower than actual VO2Max I was wondering if the 85-90% refers to that or the actual highest measured VO2 of the athlete.

Your estimate of 70-75 mL/min/kg vs 82 kind of gives answer to that and I was looking for a confirmation.

I think the VO2 drift is referring to the slow part of oxygen uptake kinetics, which Krebs goes on about quite a bit...

Sure enough plug in "vo2 drift" to google and the first link is

http://www.slowtwitch.com/mainheadings/coachcorn/slowcomponent.html
Rather, it is in the narrow mention of another set of physiological observations, some of which you've heard of, some you haven't: VO2 drift, the slow component of VO2, and heart rate drift. If you've heard of any of these it is the latter, and there is only a loose correlation between the increase in heart rate and in oxygen consumption or "uptake."

Here's a corresponding example of Krebs banging on about oxygen uptake kinetics:

Krebs cycle said:
whatever it is you think acoggan was trying to explain, it certainly was not anything to do with the non-existence of variation in aerobic/anaerobic contribution between, or even within, individuals. Even you, with your complete lack of understanding of human physiology, know that different people can be more or less aerobic or anaerobic. People who are more "aerobic" demonstrate faster O2 uptake kinetics than people who are anaerobic. This is published far and wide in the scientific literature. So before you make more of a fool of yourself with your school boy understanding, instead of trawling my posts and asking me to explain it for you, why don't YOU go and learn what O2 uptake kinetics means and what the term O2 deficit means. Maybe then you'll figure out why it is possible for some athletes to generate 80% of their ATP from oxidative phosphorylation during a 4min maximal effort whereas others may only generate 70%.
 
Jul 10, 2009
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Fidolix said:
"I am really a nobody, just another bloke who rides his bike."

Really?

If this really bothers you this much, I am 41 yo masters racer whose biggest investment to cycling is a couple of Cervelos and most remarkable financial connection is that a good friend of mine has a bike shop where I can get a good discounts.

I work in a software company where my business partners probably couldn't name a single current bicycle rider. My main education is in economics.

I accidentally ended up reading cyclingforums.com a few years back and thanks mostly to Andy Coggan's inspiring writing (if you read this, thanks Andy!) I got interested in physiology and physics of cycling. Have read a couple of elementary exercise books (you want a list? You'd be surprised how much you'd learn in comparision to this forum) so that I understand some very basic concepts and can follow simple scientific discussion related.

I coach a couple of friends who are low level hobby racers and one national level trackie. I get no money for the coaching but I find it interesting. I was myself in top10 in this years masters nationals. If you know anything of the level of cycling here and put those into that context I think you can arguably say that "I am really a nobody, just another bloke who rides his bike."

I have no idea and couldn't care less who Krebs is.
 
Jul 10, 2009
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Dear Wiggo said:
Your link says 21.13 or 21,130. 230 joules isn't going to have much impact on the results.

Yes, exactly as I said, it doesn't make much difference.

Edit: had a wrong value of 21,3kJ in the original post. That was a typo, sorry.
 
Sep 29, 2012
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_frost said:
If this really bothers you this much, I am 41 yo masters racer whose biggest investment to cycling is a couple of Cervelos and most remarkable financial connection is that a good friend of mine has a bike shop where I can get a good discounts.

I work in a software company where my business partners probably couldn't name a single current bicycle rider. My main education is in economics.

I accidentally ended up reading cyclingforums.com a few years back and thanks mostly to Andy Coggan's inspiring writing (if you read this, thanks Andy!) I got interested in physiology and physics of cycling. Have read a couple of elementary exercise books (you want a list? You'd be surprised how much you'd learn in comparision to this forum) so that I understand some very basic concepts and can follow simple scientific discussion related.

I coach a couple of friends who are low level hobby racers and one national level trackie. I get no money for the coaching but I find it interesting. I was myself in top10 in this years masters nationals. If you know anything of the level of cycling here and put those into that context I think you can arguably say that "I am really a nobody, just another bloke who rides his bike."

I have no idea and couldn't care less who Krebs is.

Yeah give me the list of textbooks. Especially the ones where you learnt about oxygen uptake kinetics. And perhaps explain why you previously said this:

July 2009
_frost said:
I am new to cycling and naive, can you tell me what's the difference?

And this, in a recent discussion on Wiggins and his cadence.
_frost said:
Well, the energy production processes are quite basic, aerobic/anaerobic energy production and oxygen deficiency are one of the first things that you learn in eg. coaching courses.

I have learned about cellular energy production at high school biology. Perhaps there are differences in levels of education in various countries.

I tend to agree with people who are right and I have no problem admitting that in this matter there are much smarter folks here. However I presented these same issues (pursuiters having large VO2Max, critical power calculation to relate Wiggins' pursuit power and later TdF performances) already 2009 when this first came out so I wouldn't call myself a sheep just for agreeing.

Did you present these issues on this forum? Coz I went looking. And in 2009 you said you were new to cycling and naive...
 
Jul 10, 2009
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Dear Wiggo said:
Yeah give me the list of textbooks.

Two of the most recent:

The Biochemical Basis of Sports Performance
Ronald J Maughan, Michael Gleeson

Physiology of Sport and Exercise
Jack H. Wilmore, W. Larry Kenney

They were both used and not the latest edition so I got them at very good price, but I don't have the reciept from Amazon anymore. I didn't realise I'd be under this heavy investigation.

Especially the ones where you learnt about oxygen uptake kinetics.

Can't remember exactly if those cover oxygen uptake kinetics largely but that is a topic that has been discussed quite many times in various forums and several blogs all over the Interwebs eg. here http://www.pponline.co.uk/encyc/the-slow-component-of-vo2-understand-it-to-go-faster-39797

And perhaps explain why you previously said this:
July 2009

Ever heard about sarcasm? The atmosphere in clinic at that time was "hahaa, you only watch cycling in July you don't understand a ****" so I tried to play along and challenge the poster to reveal his ignorance.

Add to that I really am not native english speaker but my mother tongue is one of the rare western European that is not anyhow related to germaniac languages so I might express myself "wrongly" sometimes on no purpose.

I wasn't new and naive to cycling. I know it's all very horrible, I am deeply sorry for saying that.

And this, in a recent discussion on Wiggins and his cadence.


Did you present these issues on this forum? Coz I went looking. And in 2009 you said you were new to cycling and naive...

I went back to look to and indeed I didn't actually give the CP-calculations, though I did them in my head or maybe used a spreadsheet based on numbers under discussion and just simply stated that the given numbers match (not saying anything about their reliability or how they were achieved in the first place). My mistake.
 
Sep 29, 2012
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_frost said:
Ever heard about sarcasm? The atmosphere in clinic at that time was "hahaa, you only watch cycling in July you don't understand a ****" so I tried to play along and challenge the poster to reveal his ignorance.

For your very first post?

The only Finnish I remember is mina rakastan sinua and hali minua. Not really appropriate here...
 
Jul 10, 2009
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Dear Wiggo said:
For your very first post?

The only Finnish I remember is mina rakastan sinua and hali minua. Not really appropriate here...

Yes, the first post here. I have posted and read several other forums before so maybe I wasn't thinking too much that there might be rules governing your first post ;).

Don't say, it looks like the tone of our conversation is settling at such speed that if it continues like this we soon find ourselves sitting in a pub and drinking Koskenkorva (if you know that much finnish you must know what it is?) and in a situation like this it usually ends up hugging and hitting each other's backs repeating "vittu sä oot hyvä jätkä, tiäksä sen" (damn, you're a good bloke, you know that) :D
 
Jul 12, 2012
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Don Quixote said:
Interesting stuff.

How accurate is the Nadler equation wrt calculating the bv for a trained athlete?

Most likely not accurate enough to support an argument. Personally, both in myself and others, I have never seen a loss in absolute power resulting from weight loss, if done gradually.