Ecdysteroids
Also referred to as 'FD sterone' in the title. A class of compounds found in insects and plants (like spinach and Rhaponticum carthamoides), structurally similar to mammalian steroids and found in some in vitro research to increase muscle protein synthesis. A recent study (Eisenman et al.) showed moderate gains, but the supplement was significantly underdosed compared to its label claims.
Videos Mentioning Ecdysteroids

Drug Testing, New Supplement Research, Squat Science, and Dr. Eric Helms (Podcast Episode 8)
Stronger By Science
Also referred to as 'FD sterone' in the title. A class of compounds found in insects and plants (like spinach and Rhaponticum carthamoides), structurally similar to mammalian steroids and found in some in vitro research to increase muscle protein synthesis. A recent study (Eisenman et al.) showed moderate gains, but the supplement was significantly underdosed compared to its label claims.

The Science of How to Optimize Testosterone & Estrogen
Andrew Huberman
Molecules found in plants like spinach, structurally similar to cholesterol, that appear to have anabolic effects, increasing muscle mass and strength.