Look I found this in my archives. I think it was coming from Duchaine's book, dunno where but anyway here you have the answer, NO:
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Clenbuterol is a selective beta-2 agonist that is used to stimulate the beta receptors in fat and muscle tissue in the body. Clenbuterol exhibits most of it's effects on the stimulation of both type 2 and 3 beta receptors. Clenbuterol is really one of bodybuilding's most misunderstood performance enhancement drugs. It is true that it is effective in helping to burn bodyfat but it is often been stated that clenbuterol is effective in causing anabolic gains and has in times even been compared to some of the weaker anabolic steroids. Books such as the World Anabolic Review, 1996, by P. Grunding and M. Bachmann state incorrectly that, "its effects, however, can by all means be compared to those of steroids. Similar to a combination of Winstrol Depot and Oxandrolone...." These statements are inaccurate and misleading to say the least. A lot of these claims as to the anabolic effects of clenbuterol are derived from studying the effects of clenbuterol on livestock. Clenbuterol is effective in increasing muscle mass and decreasing fat loss in animals. The problem with the variation in anabolic effects between humans and livestock is that livestock have an abundance of the type 3 beta receptors whereas humans have little if any of the type 3 beta receptors. These beta-3 receptors increases insulin secretion and sensitivity, causing more glucose and amino acids to be transported into skeletal muscle thus causing the anabolic effects that we, humans, just aren't seeing. As Dan Duchaine stated in his Muscle Media article on clenbuterol, "In those animal research studies showing an anabolic effect from clenbuterol, it's my guess the anabolism happens specifically when the beta2 receptor stops working. At that point, the beta3 increases and causes the anabolic effect through insulin mechanisms." Since humans, again, have either very little or no beta-3 receptors, there is no chance of this anabolic effect. Just another of the studies where everyone assumed that what works in animals must work in humans. This is just simply not the case with clenbuterol.
Clenbuterol does work effectively as a fat burner though. It does this by slight increases in the body temperature. With each degree that the temperature in your body is raised from the use of clenbuterol, you will burn up approximately an extra 5% of maintenance calories. This makes it effective as a fat burner. Your body will fight this by cutting down on the amount of active thyroid in the body as well as through beta receptor down regulation which explains why you only have a limited effective period to take clenbuterol. While I am on the subject of beta receptor down regulation, I would like to dispose of another myth. This involves the two on/two off cycling theory that I believe was originated by Bill Phillips in the Anabolic Reference Guide and has somehow made it's was into every other steroid book since then including the WAR and Physical Enhancement with an Edge. The two on-two off theory simply will not work because of one main reason: the half life of clenbuterol. This 2-on/2-off idea was a THEORY ONLY, not by a doctor or scientist, and not based on specific knowledge of clenbuterol, but derived by imitation from other drug's with shorter half lives.
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Clenbuterol is a selective beta-2 agonist that is used to stimulate the beta receptors in fat and muscle tissue in the body. Clenbuterol exhibits most of it's effects on the stimulation of both type 2 and 3 beta receptors. Clenbuterol is really one of bodybuilding's most misunderstood performance enhancement drugs. It is true that it is effective in helping to burn bodyfat but it is often been stated that clenbuterol is effective in causing anabolic gains and has in times even been compared to some of the weaker anabolic steroids. Books such as the World Anabolic Review, 1996, by P. Grunding and M. Bachmann state incorrectly that, "its effects, however, can by all means be compared to those of steroids. Similar to a combination of Winstrol Depot and Oxandrolone...." These statements are inaccurate and misleading to say the least. A lot of these claims as to the anabolic effects of clenbuterol are derived from studying the effects of clenbuterol on livestock. Clenbuterol is effective in increasing muscle mass and decreasing fat loss in animals. The problem with the variation in anabolic effects between humans and livestock is that livestock have an abundance of the type 3 beta receptors whereas humans have little if any of the type 3 beta receptors. These beta-3 receptors increases insulin secretion and sensitivity, causing more glucose and amino acids to be transported into skeletal muscle thus causing the anabolic effects that we, humans, just aren't seeing. As Dan Duchaine stated in his Muscle Media article on clenbuterol, "In those animal research studies showing an anabolic effect from clenbuterol, it's my guess the anabolism happens specifically when the beta2 receptor stops working. At that point, the beta3 increases and causes the anabolic effect through insulin mechanisms." Since humans, again, have either very little or no beta-3 receptors, there is no chance of this anabolic effect. Just another of the studies where everyone assumed that what works in animals must work in humans. This is just simply not the case with clenbuterol.
Clenbuterol does work effectively as a fat burner though. It does this by slight increases in the body temperature. With each degree that the temperature in your body is raised from the use of clenbuterol, you will burn up approximately an extra 5% of maintenance calories. This makes it effective as a fat burner. Your body will fight this by cutting down on the amount of active thyroid in the body as well as through beta receptor down regulation which explains why you only have a limited effective period to take clenbuterol. While I am on the subject of beta receptor down regulation, I would like to dispose of another myth. This involves the two on/two off cycling theory that I believe was originated by Bill Phillips in the Anabolic Reference Guide and has somehow made it's was into every other steroid book since then including the WAR and Physical Enhancement with an Edge. The two on-two off theory simply will not work because of one main reason: the half life of clenbuterol. This 2-on/2-off idea was a THEORY ONLY, not by a doctor or scientist, and not based on specific knowledge of clenbuterol, but derived by imitation from other drug's with shorter half lives.