On it’s own, the base trenbolone hormone has a half-life of about 6-8 hours. Although not many bodybuilders use the base hormone. Most athlete are injecting a version of trenbolone that has an ester chain attached to it, and it is not until plasma lipases in the blood stream cleave off the ester chain that trenbolone is free to interact with androgen receptors in muscle cells. The active half-life of the acetate ester version is of about 48 hours, while the enanthate version is about 5-7 days. The Hexahydrobenzylcarbonate (Cyclohexylmethylcarbonate) ester chain being the longest at 8-10 days. Though, due to the lack of scientific consensus, some of these figures can be off by about 10-20%.