Trenbolone is a 19-nor derived steroid, in the 19-nor Testosterone (Nandrolone) family. In fact, Trenbolone is structurally similar to Deca-Durabolin, differing in the fact that it has a c-9 and c-11 double bond. The c9 bond serves to prevent any aromatization (conversion) to estrogen, and thus we see far less water retention with Trenbolone when we compare it to Deca-Durabolin. Unlike nandrolone however The c11 double bond also seems to increase Androgen Receptor binding quite profoundly (this may also have something to do with the c9 bond as well). This lack of estrogenic activity and powerful ability to bind to the androgen receptor combine to make Trenbolone a much more powerful androgen than Deca, however. It also virtually eliminates all water gain and makes the majority of weight gained on this drug (at least in animal studies) virtually all new, quality muscle.  This has been anecdotally replicated in human “studies” (read: athletes who use Trenbolone) many times over.
Trenbolone also has the advantage of significantly increasing the level of the extremely anabolic hormone IGF-1 within muscle tissue as well as in the liver.  Not only does it increase the levels of IGF-1, by over 200%, it also causes increased sensitivity to this potent growth factor .
Trenbolones binding affinity to the androgen receptor (AR) is significantly strongly than testosterone , and this also contributes to anabolism as well as fat loss. Trenbolone currently holds the distinction of being the steroid that binds most tightly to the AR, currently in circulation today.
Trenbolone promotes nitrogen retention in muscles , thus helping to build new tissue, as well as being able to interact with the receptors of the anti-anabolic (muscle growth preventing) glucocorticoid hormones , and thus may also reduce levels of the highly catabolic (muscle destroying) hormone cortisol. In animal studies, it has also been shown to improve feed efficiency and mineral absorption. This serves to make the food you eat more productive in building new muscle tissue, and makes it a very effective agent with regards to nutrient partitioning. Since androgen receptors are found in lipid cells as well as muscle cells , Trenbolone can act directly on the AR in both of these types of cells to initiate anabolism as well as lipolysis (fat-burning). In addition, Trenbolone significantly promotes red blood cell production and also increases the rate of glycogen replenishment, both of which serve to profoundly improve recovery.
The only draw back to Trenbolone is that it seems to reduce aerobic capacity in its users, probably owing to bronchial dilation from increased prostaglandin formation. Also, since it’s a progestin, it can exacerbate the estrogenic effects of aromatizable steroids.
Doses are usually in the 75-100mg range, and since the ester length of this steroid is quite short it needs to be administered via intramuscular injection every day to every other day, and Trenbolone is a favorite on both bulking as well as cutting cycles. It should be noted that it is typically used primarily in cutting cycles, since it is a very potent fat-loss agent.
Trenbolone can be found widely on the Black Market, and implants for cattle are frequently converted into an injectable or transdermal compound. Trenbolone, whether it’s made from cattle implants or bought on the black market pre-made, is typically and significantly more expensive than other anabolic steroids ranging from 15 U.S dollars per gram of powder up to 150 U.S for a single 10 ml bottle