What is the 'GW1516' that got Amos in trouble?

GW1516 has not been approved for medication and has no recognised therapeutic uses. The World Anti-Doping Agency (WADA) has advised of its health risks for athletes.

In 2017, there were 31 sanctions related to this compound worldwide. GW1516 is known by many names including cardarine and endurobol. According to the United States Anti-Doping Agency (USADA), GW1516 is often advertised as a selective androgen receptor modulator and is prohibited under the S4.5 Metabolic Modulators on the WADA prohibited list. Substances in this category modify how the body metabolises fat and GW1516 was originally synthesised and evaluated for the treatment of obesity, diabetes, and other disorders caused by metabolic problems.