Proviron (Mesterolone) is used to replace testosterone in men with hypogonadism. Male hypogonadism is a condition when the body does not produce enough testosterone. Testosterone is a natural male hormone, known as an androgen, which controls normal sexual development in men.
Testosterone is essential for the development and maintenance of the male reproductive organs as well as other male characteristics, such as hair growth, deep voice, sexual drive, muscle mass and body fat distribution.
Proviron is for use in male patients only. It carries four primary traits that largely define its mode of action. First and foremost, the Proviron hormone has a strong binding affinity to Sex-Hormone-Binding-Globulin (SHBG). Thus, it appears to be one of the strongest anabolic steroids in this regard. By binding to SHBG, a hormone partially responsible for reducing free testosterone, binding SHBG will enhance the amount of circulating free testosterone.
It also has the ability to interact with the aromatase enzyme, the enzyme responsible for the conversion of testosterone to estrogen. By binding to the aromatase enzyme, Proviron can actually inhibit aromatase activity, thereby offering protection against estrogenic side effects. It will not carry an anti-estrogenic effect near the level of power of an Aromatase Inhibitor (AI) but it will be notable. Depending on the nature of the cycle the individual undertakes it is quite possible for Proviron to take care of all your anti-estrogen needs.
However, it is not going to be a foundational steroid during a bulking phase, and for most men it will not have a place in an off-season cycle. Adding in Proviron could possibly help the individual breakthrough a sticking point during his cycle. At some point and time in all cycles the progress begins to wane, and in some cases come to a complete halt.
In summary it enhances the total free state of the other steroids being used in a stack, it could possibly help the individual breakthrough this sticking point. During the off-season, this is where most will use the largest amount of testosterone.