FoxxyBrown1111 said:
As i always said: Most performance enhancing of Doping comes from the placebo effect.
I once posted many studies which came to this conclusion. Somehow it got lost here, may because it didn´t fit in the opinions here.
Not working are:
1.) Nandrolon
2.) human growth hormone
3.) steroids (at leat not in endurance cycling)
4.) morphine
and last but not least: EPO; at least it´s not "working" the way people think it works (higher hct = better performance).
I am not a scientist, but the studies were made by scientists, so i´ve to trust them.
there is a very good review article by Martial Saugy on detection methods for growth hormone (from around 2004 - 2005, if i remember well) in which he clearly says that there never is any agreement between well-controlled scientifc studies and the claims made by the athletes who actually use PEDs. and he says why: he says this is because the doping athlete takes more, she/he takes it for a longer period of time, she/he takes it in combination with other drugs*, she/he takes doses that are tailored to her/his sport and tailored to the calendar of events she/he intends to compete in and, most importantly, tailored to their response to the drug.
for example in the article, Saugy says that in doping, growth hormone is given in doses up to 8.3 mg per day. but in any well-controlled study i have ever read, the highest dose given to the subjects was probably 0.065 mg/kg, meaning 4.8 mg for a subject weighing 75 kg.
why 0.065 odd mg/kg? because this is the highest dose recommanded by the manufacturers.
and the first well-controlled scientific study to demonstrate that testosterone does work (and that it works in a dose-dependend manner) did so by using humongous doses of 600mg once a week (the dose recommanded by the manufacturer is 1000 mg once every 3 months) and by assigning the subjects to strict diets. the article is by Shalender Bashin, who has done a lot of work on the subject.
also, this observation by petesam is very correct:
petesam said:
A quick look over it suggests that it's a pretty dubious trial though for the following reasons: no statement of group size & small differences between groups - therefore no ability to state confidence or reliability of the results, same people in each group?
(...)
i'm sorry to say it's probably not worth drawing too many conclusions from. Too easy to agree with researchers' conclusions, even though they're often not very well founded
it is very true and it is also a general problem of doping rerearch: the problem with scientific studies of this kind is that they have to use statistics to make their conclusion but the researchers doing the piece of work are actually physiologists, medical doctors, chemists, pharmacologists... they know how to run statistical test X (they know how to press a bouton on their computer), but often, they do not understand the assumptions of the test - in kinder words: they don't always pay enough attention as to whether statistical test X is able to deal with the setup of their current study (one of the reasons why they don't pay enough attention is because when running a statistical test, the test automatically calculates a reliability estimate that says: "the stuff i've just calculated is reliable to x %", and they take it to mean that everything is statistically sound).
so doping researchers are not expert statisticians, and sometimes they get their study designs wrong, or they get their final stats wrong.
and therefore, we should not believe everything that is being published.
when i was preparing for my viva as a phd student, i remember going through one research article by one of my examiners that had appalling statistical quality. and yet he is a very renowned scientist in his field.
speaking about statistics, another reason why studies investigating the PED effects of X fail to identify any doping effect is probably because they always use very small sample sizes.
Liu and co-workers have done a very interesting work that shows this: they reviewed all the well-controled studies ever published on growth hormone as a PED and wanted to see if by averaging the results of these studies, they could come to the conclusion that growth hormone is effective as a doping agent (sorry i can't remember the year, but the article should be easy to google up with the key words "meta analysis" "growth hormone" "doping"). they only managed to gather about 30 studies; these studies used a total of 450 odd subjects. this makes an average of 15 subjects per well-controled study (suitable for comparison) on growth hormone as a PED in the last decade or so.
the rules of statistics say that when a small sample size is used (like in the growth hormone example here: 15 subjects, say 8 subjects with growth hormone compared to 7 subjects with placebo) your comparison will only be reliable statistically if the difference between the 2 groups is a big difference. and i think when i say big difference, on 15 subjects, using growth hormone alone, and in small quantities, i really mean big difference; of the kind that you can tell by just watching them pedal, you don't need any statistical analysis anymore.
and so, these studies with small sample sizes are probably fundamentally flawed from the beginning, because they are looking (only able to look) for large variations using a single input parameters whereas doping is about fine-tuning one's performance by varying many different parameters.
the design of these "well-controled" studies is derived from the clinical trials run in the pharmaceutical industry where people want to verify that drug X does effectively lower your blood pressure, for example, but doping is quite different, i guess it would probably need its own type of studies.
*regarding the fact that PEDs are often taken as combinations, i was just thinking: FoxxyBrown1111 mentions a study that found that EPO doesn't work. maybe they have forgotten to also administer iron to the subjects before administering EPO.