The term “SARM” is an acronym for Selective Androgen Receptor Modulator. These are a class of drugs known for their performance-enhancing abilities. They are similar to anabolic steroids but are engineered to offer targeted effects to minimize side effects. The pharmaceutical industry initially developed SARMs to address diseases such as muscle degeneration and osteoporosis, among others, hoping to provide a safer alternative to steroids for some medical treatments. However, their usage has since extended into the world of fitness and bodybuilding for their muscle growth, strength enhancement, and fat reduction properties.

Note: While MK 677, SR-9009, and GW-501516 are commonly referred to as SARMs, they do not affect the Androgen Receptor and thus are not true SARMs. To keep it simple, we will refer to these three as SARMs for the rest of this book.

Critical Characteristics of SARMs

Selective Action: SARMs were designed to bind selectively to androgen receptors in muscle and bone. This selectivity is what gives SARMs their reputation for having fewer side effects compared to anabolic androgenic steroids.