Anabolic steroid

Anabolic-androgenic steroids (AAS) are a class of synthetic androgens structurally derived from testosterone. They were developed in the 1930s and 1940s for clinical use in hypogonadism, muscle-wasting disease, and delayed puberty, and have since been used non-medically to increase skeletal-muscle mass, strength, and recovery capacity.

AAS are the canonical example of a substance whose use disqualifies an athlete from the natty designation. They appear on WADA’s prohibited list under category S1 (“Anabolic Agents”) and are controlled substances under the U.S. Anabolic Steroids Control Act (Schedule III).

Mechanism

Anabolic steroids bind to the androgen receptor, increasing intracellular signalling for muscle protein synthesis and suppressing protein catabolism. They also produce androgenic effects: increased erythropoiesis, bone density, secondary sexual characteristics, and (often) negative effects on the hypothalamic–pituitary–gonadal axis.

Distinction from peptides

Anabolic steroids are small-molecule lipid hormones, distinct from the peptide hormones catalogued elsewhere on Retapedia. Many peptides indirectly affect anabolism (for example, growth hormone secretagogues acting on the GH/IGF-1 axis), but the binding mechanisms and regulatory classifications are separate.

Selective alternatives

Selective androgen receptor modulators (SARMs) were developed to retain the anabolic effect of AAS while reducing androgenic side effects. SARMs are also prohibited in tested sport.