OK, I'll question the isotope test.

wimpyVO2 said:

Zoom in and look at Chart 6

http://wwwrcamnl.wr.usgs.gov/isoig/projects/fingernails/images/OpenHouse2003_B.pdf

Travel from the United States to Europe will increase your carbon-13
delta from -17 to -21, due to variations in local foods.

Yeah and now the dehydration on the flight will get ya too.

wimpyVO2 said:

Quoted message said:

Travel from the United States to Europe will increase your carbon-13
delta from -17 to -21, due to variations in local foods.

Stu Fleming said:

Yeah and now the dehydration on the flight will get ya too.

And if it doesn't the liquids might.

The variability for the del 13C is really not very much at all...review
of the differences reveal about 2 permil (2 parts pre thousand) for all
the people who worked on the project (it appears the researchers were
primarily Asian...) I doubt that all of these people exist on the same
diet. The chart indicates the del 13C for the diet of people living in
the US varies by about 1 permil. So, the results are actually quite
predictable given diet. BTW...have the del 13C results for Landis been
posted w/# for natural vs. synthetic?

- Fred B.

wimpyVO2 said:

Zoom in and look at Chart 6

http://wwwrcamnl.wr.usgs.gov/isoig/projects/fingernails/images/OpenHouse2003_B.pdf

Travel from the United States to Europe will increase your carbon-13
delta from -17 to -21, due to variations in local foods.

And I'm supposed to believe that Floyd's carbon-13 results can only be
explained by doping?

Quoted message said:

The variability for the del 13C is really not very much at all...review
of the differences reveal about 2 permil (2 parts pre thousand) for all
the people who worked on the project (it appears the researchers were
primarily Asian...) I doubt that all of these people exist on the same
diet. The chart indicates the del 13C for the diet of people living in
the US varies by about 1 permil. So, the results are actually quite
predictable given diet. BTW...have the del 13C results for Landis been
posted w/# for natural vs. synthetic?

3.99 according to Michael Henson, Landis' spokesman. Three is the
threshold.

http://online.wsj.com/public/article/SB115522290517032225-Fdk3SqD84q31fQN_mbm9_kTRRqU_20060909.html?mod=tff_main_tff_top

Quoted message said:

Quoted message said:

The variability for the del 13C is really not very much at all...review
of the differences reveal about 2 permil (2 parts pre thousand) for all
the people who worked on the project (it appears the researchers were
primarily Asian...) I doubt that all of these people exist on the same
diet. The chart indicates the del 13C for the diet of people living in
the US varies by about 1 permil. So, the results are actually quite
predictable given diet. BTW...have the del 13C results for Landis been
posted w/# for natural vs. synthetic?

3.99 according to Michael Henson, Landis' spokesman. Three is the
threshold.

http://online.wsj.com/public/article/SB115522290517032225-Fdk3SqD84q31fQN_mbm9_kTRRqU_20060909.html?mod=tff_main_tff_top

In addition, the background against which the 13C:12C ratio of
testosterone is compared is another endogenous steroid, produced from
the same precursors. Whether or not diet alters the ratio therefore
isn't the question, the question is whether it alters it
*differentially* compared to the "standard".

Andy Coggan

Quoted message said:

In addition, the background against which the 13C:12C ratio of
testosterone is compared is another endogenous steroid, produced from
the same precursors. Whether or not diet alters the ratio therefore
isn't the question, the question is whether it alters it
*differentially* compared to the "standard".

Andy Coggan

According to WADA's own study, apparently it can, and quickly too.

http://www.bgc-jena.mpg.de/service/iso_gas_lab/gasir2005/GasiR_2005_Program_and_Abstracts.pdf

I also found it interesting that the "did not exceed 3%" statement was
crossed out....hmmmm, I wonder what that means...

Tom_A said:

Quoted message said:

In addition, the background against which the 13C:12C ratio of
testosterone is compared is another endogenous steroid, produced from
the same precursors. Whether or not diet alters the ratio therefore
isn't the question, the question is whether it alters it
*differentially* compared to the "standard".

Andy Coggan

According to WADA's own study, apparently it can, and quickly too.

http://www.bgc-jena.mpg.de/service/iso_gas_lab/gasir2005/GasiR_2005_Program_and_Abstracts.pdf

I also found it interesting that the "did not exceed 3%" statement was
crossed out....hmmmm, I wonder what that means...

It looks like it may be a printing/publishing issue. Since that is also
in CAPS it may be intended to be underlined for emphasis. It is
unlikely that in the papers of a conference there would be strikeouts.

Tom_A said:

Quoted message said:

In addition, the background against which the 13C:12C ratio of
testosterone is compared is another endogenous steroid, produced from
the same precursors. Whether or not diet alters the ratio therefore
isn't the question, the question is whether it alters it
*differentially* compared to the "standard".

Andy Coggan

According to WADA's own study, apparently it can, and quickly too.

http://www.bgc-jena.mpg.de/service/iso_gas_lab/gasir2005/GasiR_2005_Program_and_Abstracts.pdf

I also found it interesting that the "did not exceed 3%" statement was
crossed out....hmmmm, I wonder what that means...

Note that the subjects in this study were on a cholesterol-free diet
(thus forcing much greater reliance on endogenous precursors for the
synthesis of testosterone, etc.), and that samples were obtained 5x/d
(thus enhancing the chance of observing disequilibrium). Since no data
are shown, we also don't the magnitude of the differences that were
actually observed, except that it didn't exceed the 3 per mil cut-off
used by anti-doping authorities (as emphasized by the authors through
use of bold *and* underlined* - not crossed out - text).

Andy Coggan

Quoted message said:

I've tested positive on the isotope test. Twice. And I didn't dope.
On second test, I had to pay out of my own pocket. I'm no longer an
athlete (was never even close to being a professional one when I went
positive) and the second test was 4 months ago.

That's intersesting - who are you?

Andy Coggan

gds said:

Tom_A said:

Quoted message said:

In addition, the background against which the 13C:12C ratio of
testosterone is compared is another endogenous steroid, produced from
the same precursors. Whether or not diet alters the ratio therefore
isn't the question, the question is whether it alters it
*differentially* compared to the "standard".

Andy Coggan

According to WADA's own study, apparently it can, and quickly too.

http://www.bgc-jena.mpg.de/service/iso_gas_lab/gasir2005/GasiR_2005_Program_and_Abstracts.pdf

I also found it interesting that the "did not exceed 3%" statement was
crossed out....hmmmm, I wonder what that means...

It looks like it may be a printing/publishing issue. Since that is also
in CAPS it may be intended to be underlined for emphasis. It is
unlikely that in the papers of a conference there would be strikeouts.

OK...I'll accept that. But, can someone please point me to the results
of the study where they had riders bonk, replace 8-10k calories with
mostly plant based carbos (including a touch of beer and some of
Kentucky's "finest"😉, and then follow that up with >5 hours at max
effort and an overwhelming feeling of domination and victory with it's
resulting testosterone surge? What happens to the isotope ratios after
something like that? So far, we just have one sample point...and there
wasn't good enough control over the input.

I've got this funny feeling that, just like their baseline physiologies
are "off the charts", the response of top level athletes bodies to
things like the Stage 16/Stage 17 scenario can be widely variable with
respect to these tests.

The more I learn about both the T/E ratio test and the isotope test,
the more I find it them to be highly suspicious as "smoking gun" type
tests. They appear to be methods to indicate POSSIBLE testosterone
doping, but fall short of being absolute indicators.

But...those tests are the best we have so far to try to detect this
type of doping. Damn.

Quoted message said:

Note that the subjects in this study were on a cholesterol-free diet
(thus forcing much greater reliance on endogenous precursors for the
synthesis of testosterone, etc.)...>

Wait a minute...does this mean that if any animal products would be
consumed, it could have an additional effect on the isotope ratio
comparison?

What if the "animal product" consumed had an isotope ratio similar to
the signature of exogenous testosterone?

Please educate me. Thanks.

Tom_A said:

Quoted message said:

OK...I'll accept that. But, can someone please point me to the results

of the study where they had riders bonk, replace 8-10k calories with
mostly plant based carbos (including a touch of beer and some of
Kentucky's "finest"😉, and then follow that up with >5 hours at max
effort and an overwhelming feeling of domination and victory with it's
resulting testosterone surge? What happens to the isotope ratios after
something like that? So far, we just have one sample point...and there
wasn't good enough control over the input.

I've got this funny feeling that, just like their baseline physiologies
are "off the charts", the response of top level athletes bodies to
things like the Stage 16/Stage 17 scenario can be widely variable with
respect to these tests.

The more I learn about both the T/E ratio test and the isotope test,
the more I find it them to be highly suspicious as "smoking gun" type
tests. They appear to be methods to indicate POSSIBLE testosterone
doping, but fall short of being absolute indicators.

But...those tests are the best we have so far to try to detect this
type of doping. Damn.

Well, I don't know of the study you want to see but I think there is
the possibility of looking at those questions quite easily. There are
many, many samples taken from many, many riders on all the stages of
the Tour. So, if all of these are negative save one there is a pretty
strong implication that riding a bicycle hard and eating a lot doesn't
cause the result obtained. Anf FL himself seems to have not tested
positive on any other stage. Are you suggesting that he wasn't riding
hard or eating a lot on any other day.

gds said:

Well, I don't know of the study you want to see but I think there is
the possibility of looking at those questions quite easily. There are
many, many samples taken from many, many riders on all the stages of
the Tour. So, if all of these are negative save one there is a pretty
strong implication that riding a bicycle hard and eating a lot doesn't
cause the result obtained. Anf FL himself seems to have not tested
positive on any other stage. Are you suggesting that he wasn't riding
hard or eating a lot on any other day.

No...I'm saying he didn't bonk and then follow it up with a maximal,
victorious ride at any other point...I don't think any of the other
riders did either. Besides, everyone is different in their responses
to efforts and stress...

However, due to the cost, the isotope ratio test isn't done unless the
T/E ratio test is over the limit first. So...there's absolutely NO
additional data on the effects on the isotope ratios from all those
additional tests.

Also, remember, what's been revealed is that the high ratio of T/E in
Landis' test sample wasn't due to a massive increase in testostorone,
but a massive decrease in epitestosterone...a hormone that, according
to the information I've looked at, has a lot of questions attached to
it on it's purpose, it's production, and it's sensitivity to various
scenarios encountered in athletic settings. Again, it's another test
with a bunch of question marks to it...

Tom_A said:

gds said:

Well, I don't know of the study you want to see but I think there is
the possibility of looking at those questions quite easily. There are
many, many samples taken from many, many riders on all the stages of
the Tour. So, if all of these are negative save one there is a pretty
strong implication that riding a bicycle hard and eating a lot doesn't
cause the result obtained. Anf FL himself seems to have not tested
positive on any other stage. Are you suggesting that he wasn't riding
hard or eating a lot on any other day.

No...I'm saying he didn't bonk and then follow it up with a maximal,
victorious ride at any other point...I don't think any of the other
riders did either. Besides, everyone is different in their responses
to efforts and stress...

However, due to the cost, the isotope ratio test isn't done unless the
T/E ratio test is over the limit first. So...there's absolutely NO
additional data on the effects on the isotope ratios from all those
additional tests.

Also, remember, what's been revealed is that the high ratio of T/E in
Landis' test sample wasn't due to a massive increase in testostorone,
but a massive decrease in epitestosterone...a hormone that, according
to the information I've looked at, has a lot of questions attached to
it on it's purpose, it's production, and it's sensitivity to various
scenarios encountered in athletic settings. Again, it's another test
with a bunch of question marks to it...

Hey, I don't profess to know the ultimate truth. But the T to E test
was run on many days on many riders. There is lots of bonking and lots
of maximal efforts.

Only one came back positive. You are trying to define the issue much
too narrowly. You want to know how these tests discriminate when one
person, Floyd Landis, eats a certain diet and has a really bad day
followed by a really good day.
Come on. The standard that you are proposing means that you would need
to calibrate a test for every single individual over all possibilities
of diet and exertion. That is simply nonsense.
Perhaps the results are a fluke. But to argue that nothing means
anything because you don't know xyz is childish.

BTW if I understand this all correctly the isotope test is run only
after a postiive for T to E as a confirmation (or not) test. So what we
have is FL first being the only rider to test postive on the T to E
test and then he was also shown to have exogenous T via the follow up
test.

gds said:

Hey, I don't profess to know the ultimate truth. But the T to E test
was run on many days on many riders. There is lots of bonking and lots
of maximal efforts.

Only one came back positive. You are trying to define the issue much
too narrowly. You want to know how these tests discriminate when one
person, Floyd Landis, eats a certain diet and has a really bad day
followed by a really good day.
Come on. The standard that you are proposing means that you would need
to calibrate a test for every single individual over all possibilities
of diet and exertion. That is simply nonsense.
Perhaps the results are a fluke. But to argue that nothing means
anything because you don't know xyz is childish.

BTW if I understand this all correctly the isotope test is run only
after a postiive for T to E as a confirmation (or not) test. So what we
have is FL first being the only rider to test postive on the T to E
test and then he was also shown to have exogenous T via the follow up
test.

I'm not asking for the "nonsense" of individual testing. I'm just
asking that the test results be put into proper perspective. Neither
of the "failed" results is a "slam dunk" indicator of exogenous
testosterone use, despite what is being claimed by many.

That one anomolous T/E ratio test was failed due to an odd 1 day
DECREASE in a marginally understood hormone, of which a reduction has
absolutely no benefit whatsoever, nor a known artificial way to cause
the reduction. Odd result #1.

Then, the isotope ratio test is just barely failed at a ratio of 3.99
parts per mil vs. the limit of 3 parts per mil....yet, there's an
overlap in "normal" ranges of the c12/c13 ratio of endogenous and
exogenous testosterone and there are studies that show that diet can
"manipulate" the ratios in the short term and there's also an unknown
response in the ratio to a bonk/refuel/victory scenario. Odd result
#2.

I'm beginning to agree with you that "Perhaps the results are a fluke".

Tom_A said:

Quoted message said:

I'm not asking for the "nonsense" of individual testing. I'm just

asking that the test results be put into proper perspective. Neither
of the "failed" results is a "slam dunk" indicator of exogenous
testosterone use, despite what is being claimed by many.

That one anomolous T/E ratio test was failed due to an odd 1 day
DECREASE in a marginally understood hormone, of which a reduction has
absolutely no benefit whatsoever, nor a known artificial way to cause
the reduction. Odd result #1.

I can't believe that the scientific literature agrees with you.
Otherwise why run the ratio test at all. Beyond that why run it on a
person multiple times. The only reasonable conclusions are 1) the ratio
test has been scientifically validated, and 2) because there are
changes from time to time.

Quoted message said:

Then, the isotope ratio test is just barely failed at a ratio of 3.99
parts per mil vs. the limit of 3 parts per mil....yet, there's an
overlap in "normal" ranges of the c12/c13 ratio of endogenous and
exogenous testosterone and there are studies that show that diet can
"manipulate" the ratios in the short term and there's also an unknown
response in the ratio to a bonk/refuel/victory scenario. Odd result

Barely failed? Looks to me that he was over by 33%.

Quoted message said:

#2.

I'm beginning to agree with you that "Perhaps the results are a fluke".

And yes it can still be a fluke, a statistical anomaly or whatever. But
I'd feel more strongly in that direction if some scientists would jump
on that bandwagon. So far it's only fans.

gds said:

I can't believe that the scientific literature agrees with you.
Otherwise why run the ratio test at all. Beyond that why run it on a
person multiple times. The only reasonable conclusions are 1) the ratio
test has been scientifically validated, and 2) because there are
changes from time to time.

Here's a statistical view of the applicability of the T/E ratio test:
http://www.amstat.org/publications/chance/172.berry.pdf

You also might want to review Thomas Fine's summary of his
investigation into the subject (with literature citings galore):

http://hea-www.harvard.edu/~fine/opinions/testosterone_d13C.html

Quoted message said:

Quoted message said:

Then, the isotope ratio test is just barely failed at a ratio of 3.99
parts per mil vs. the limit of 3 parts per mil....yet, there's an
overlap in "normal" ranges of the c12/c13 ratio of endogenous and
exogenous testosterone and there are studies that show that diet can
"manipulate" the ratios in the short term and there's also an unknown
response in the ratio to a bonk/refuel/victory scenario. Odd result

Barely failed? Looks to me that he was over by 33%.

Let's see...the limit is 3 parts per THOUSAND and in this small sample
of urine, the metabolites of testosterone compared to metabolites of
some other hormone was read to be 3.99 per THOUSAND. If you want to
characterize that as a whopping 33% over the limit...ummm, OK.
Besides, I've only seen the 3.99 number as a quote from Landis' doctor.
I don't think the public officially knows what the test results are.

Quoted message said:

Quoted message said:

#2.

I'm beginning to agree with you that "Perhaps the results are a fluke".

And yes it can still be a fluke, a statistical anomaly or whatever. But
I'd feel more strongly in that direction if some scientists would jump
on that bandwagon. So far it's only fans.

So...you're saying you feel more comfortable with the statements coming
from anti-doping scientist (like the head of the French lab) that the
tests are "infallible"? Really? Infallible?

Read the Thomas Fine summary I linked to above and tell me that either
of these tests is absolute proof of testosterone doping.

I'm not questioning the performance of the testing or the accuracy of
the tests measurements. I'm questioning the applicability of the tests
to the stated purpose...catching dopers. With so much at stake, i.e.
rider's livelihoods, I find these testosterone tests to be somewhat
lacking.

In article
<[email hidden]>,

gds said:

Hey, I don't profess to know the ultimate truth. But the T to E test
was run on many days on many riders. There is lots of bonking and lots
of maximal efforts.

Do all the folks who bonk get tested the next day? Test
everybody to promote fairness. Test everybody for
exogenous testosterone.

Quoted message said:

Only one came back positive. You are trying to define the issue much
too narrowly. You want to know how these tests discriminate when one
person, Floyd Landis, eats a certain diet and has a really bad day
followed by a really good day.
Come on. The standard that you are proposing means that you would need
to calibrate a test for every single individual over all possibilities
of diet and exertion. That is simply nonsense.
Perhaps the results are a fluke. But to argue that nothing means
anything because you don't know xyz is childish.

Test everybody.

--
Michael Press

quote= said:

Quoted message said:

The variability for the del 13C is really not very much at all...review
of the differences reveal about 2 permil (2 parts pre thousand) for all
the people who worked on the project (it appears the researchers were
primarily Asian...) I doubt that all of these people exist on the same
diet. The chart indicates the del 13C for the diet of people living in
the US varies by about 1 permil. So, the results are actually quite
predictable given diet. BTW...have the del 13C results for Landis been
posted w/# for natural vs. synthetic?

3.99 according to Michael Henson, Landis' spokesman. Three is the
threshold.

http://online.wsj.com/public/article/SB115522290517032225-Fdk3SqD84q31fQN_mbm9_kTRRqU_20060909.html?mod=tff_main_tff_top

In addition, the background against which the 13C:12C ratio of
testosterone is compared is another endogenous steroid, produced from
the same precursors. Whether or not diet alters the ratio therefore
isn't the question, the question is whether it alters it
*differentially* compared to the "standard".

Andy Coggan[/QUOTE]

Any information out there on what was used as the standard?