Testosterone Acetate ester is much faster acting than Enathate or Cypionate, and thus requires a more frequent injection schedule such as every day or every other day in order to keep blood levels as stable as possible. The benefit to this however, is that the steroid can be cleared from the body much more quickly after use is discontinued, thus making it a more preferable choice for tested athletes. Testosterone is a steroid hormone from the androgen group and is found in mammals, reptiles, birds, and other vertebrates. In mammals, testosterone is primarily secreted in the testicles of males and the ovaries of females, although small amounts are also secreted by the adrenal glands. It is the principal male sex hormone and an anabolic steroid.