What Is It?
A DHT-derived steroid with a methylated 17-position. Synthesized by Yuichiro Kanno in 2011. Despite marketing, this is not a traditional SARM.
How Does It Work?
YK-11 wears three uniforms at the same time. Marketed as a SARM. Structurally a steroid. Mechanistically a myostatin inhibitor. Partial androgen receptor agonist that upregulates follistatin, which inhibits myostatin — your body's natural cap on muscle growth. Removing that cap is why double-muscled cattle exist.
Primary Benefits (research suggests)
- Removes the myostatin ceiling on muscle growth
- Different anabolic pathway from classical SARMs
- Double-muscled phenotypes observed in myostatin-knockout animals
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- Zero human clinical trials — all data from cell cultures and rats.
- Methylation at position 17 means liver toxicity risk.
- Tendon brittleness risk (20% less tendon strain = higher tear and rupture risk).
- Testosterone suppression, fertility harm, and brain oxidative stress documented in animal models.
- WADA banned.
- For research purposes only.
Research Sources
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