Thursday, September 30, 2010

The Low Down On Clenbuterol: Did he or didn't he?

Clenbuterol, the banned substance found in small amounts in the urine of Tour de France champion Alberto Contador is a chemical of many uses and sources.
For one, the substance often referred to as “Clen” is widely used by weight lifters because of its ability to reduce the appetite while also building muscle, specifically by reducing your ratio of Fat Free Mass (FFM) to Fat Mass (FM).

That’s what every cyclist wants, especially for climbing. Clen stimulates your beta-2 receptors, which in turn help you to lose fat by allowing your body to release and burn more stored fat.

And we all know how great a climber Contador was in this year’s Tour when he dueled it out with Schleck on some of the steepest mountains known to cycling competition.

But the effectiveness of the substance for a competitive cyclist could be limited. While it is true that it could make a rider more efficient, lower in weight and better able to sustain hundreds of miles on a given level of food, it also has several drawbacks.

For one, to get maximum results, you need to take the substance for six weeks at a time—no on and off for this drug, because it just peters out, according to

There is also good reason the substance may have come from the meat he ingested, as Contador claimed in a press conference today near Madrid.

Clen has been used for decades in the foreign veterinary world, for increasing the lean yield of livestock. It’s long half life and tendency to stay active in the body for long periods of time mean that vets in the United States aren’t able to use it. Which would explain why European meat could easily have the substance in it, and why Contador could have had some of the substance excreted in his urine.

But more importantly, the fact that an effective dose of Clenbuterol must last six weeks, is the same reason why a cyclist might not be bothered, for one the risk of being caught over that period of time. But there are physiological reasons too. This is what the experts said:

“One of the primary drawbacks of Clenbuterol is that after a couple of weeks, it seems to stop working for most people. This is because it can cause a down regulation of pulmonary, cardiac and central nervous system beta-adrenergic receptors. … To counteract this, you can take some Ketotifen, Benadryl, or Periactim every 3rd or 4th week that you remain on Clenbuterol. These are prescription anti-histimines, [and] they’ll make you drowsy,” said the experts at Isteroids.

The expert goes on to say, “One of the weirdest things about Clenbuterol is that even though it’s an asthma medication, studies have shown reduced exercise (cardiovascular) performance with [it].” However, that being said, the drug is easily available on the Internet even in the United States where it is banned.  An ad for the drug at the "Droid Shop" reads, "discrete billing," and "no prescription required," and takes all credit cards.

Aside from the almost clear detraction of using the drug in cardio sports, there are other downsides to the drug, a perilous road to go down for Contador who has had a history of blood clots in his brain that almost killed him in 2004: it causes enlargement of heart ventricles in studies with animals, specifically cardiac hypertrophy, and dose dependent apoptotic and necrotic myocycte death (death of human cells). It also depletes Taurine, one of the essential amino acids for bodily function. (Though Taurine is not specifically an amino acid because it lacks carboxyl group, it acts like one.)

According to Wikipedia, Taurine crosses the blood-brain barrier and has been implicated in a wide array of physiological phenomena including “adipose tissue regulation and possible prevention of obesity, calcium homeostasis, recovery from osmotic shock, protection against glutamate excitotoxicity, and prevention of epileptic seizures. ….Additionally, supplementation with taurine has been shown to prevent oxidative stress induced by exercise.”

Clenbuterol is also an asthma medication, again not available to asthmatics in the US, but available in Europe. Did Contador take asthma medication? That’s a good question. Albuterol is Clen’s shorter acting cousin, the FDA’s drug of choice here. In the world of athletics though, Clenbuterol has a much longer history of use, according to

In the press conference today Contador said the fact that the anti-doping tests prior and after July 21 did not detect the substance, analyzed by the same laboratory in Cologne, Germany, added credence to his contaminated meat theory. Add his statement to the anatomy of this drug's effectiveness, it seems unlikely that he would have taken the drug purposefully.

On the other hand, Contador's extremely lean and extremely effective body has often led to speculation that he was taking banned substances.  But speculation seems to be the backbone of the cycling industry, especially among cycling amateurs, and in this case, proof is the preferred alternative. How the UCI will come to that outcome is not known.

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