I have somewhat followed pro cycling and all of the recent busts and confessions of pros using any number of WADA‘s banned substances. I love to hear the excuses too. Today, I saw a post online that Alberto Contador tested positive for clenbuterol on a rest day. He claims he ate some tainted beef. In Alberto Contador‘s case, I really feel that his story is valid for two reasons: 1) Clenbuterol is widely (and often illegally) used in the animal world, both for production and for competition; and 2) I don’t see how clenbuterol would be useful to a cyclist during competition.
What is clenbuterol?
Clenbuterol is a beta- agonist normally used like albuterol for asthma and COPD. Peripherally, it acts as a stimulant and thermogenic aid, resulting in fat loss without the associated muscle loss, and even a muscle gain. It is used in pork, lamb, and beef stock to increase muscle to fat ratio, especially when animals are kept in conditions not allowing for much movement, and is also used in horses for competition.
So, what is so bad about clenbuterol?
Clenbuterol administered chronically has been shown to decrease exercise tolerance by a downregulation of the beta- adrenergic receptors. It does not have this effect acutely, for the adaptation takes a bit of time. Not to mention the long-term cardiovascular damage purported.
How on Earth?
Clenbuterol has a half-life of approximately 10.4 days, and it partitions into the muscle. Without going into the pharmacokinetics of the drug, it seemsmore likely than some hydrophilic drugs to remain in meat for consumption. There are studies out there showing that enough remains in the meat of animals on clenbuterol chronically, and there have been reported incidences of people getting ill from clenbuterol in their meat:
And, hey, it’s in vogue with celebrities, although it’s banned in any form in the U.S. http://www.independent.co.uk/life-style/health-and-families/health-news/clenbuterol-the-new-weightloss-wonder-drug-gripping-planet-zero-441059.html
DISCLAIMER: I am not an expert on performance enhancing drugs, professionally or personally. If I am missing part of the picture (which I know I most likely am), please enlighten me.