While an AI inhibits all estrogen, a SERM just prevents its negative effects by blocking estrogen's androgenic properties.
SERMs signal the pituitary to produce Leutenizing and follicle stimulating hormones.
These hormones produced by the pituitary gland are responsible for signalling the testicles to produce testosterone.
This is the generally accepted concept behing the use of a SERM, it is usually included in physician guided treatments to restore the hpa otherwise known as PCT.
SERM AI PCT