Research has shown that YK-11 inhibits myostatin. How does it do this? YK-11 induces muscle cells to make more follistatin which is a strong myostatin inhibitor. Myostatin (also known as growth differentiation factor 8) as a myokine, a protein produced by muscle cells that acts on muscle cells to inhibit myogenesis. Myogenesis is muscle cell growth and differentiation. Research through the years show that when you block myostatin, it allows for significantly more muscle mass.
Initial Research by Japanese Researcher, Yuichiro Kanno, in 2011 at Toho University, has shown that “YK-11” attaches itself to the androgen receptor and makes muscle cells produce more anabolic factors. He also discovered that “YK-11” induces the muscle cells to produce more follistatin, which decreases myostatin and increases muscle growth through this mechanism, as well. YK-11 selectively binds to the androgen receptors similarly to LGD-4033, and MK-2866. That is to say, that YK-11 offers great promise as therapy for muscle wasting illnesses, and for promoting very massive muscle gains. Much like MK-2866, and LGD-4033, YK-11 binds to the androgen receptors in muscle, and bone. YK-11 is weakly anabolic to androgenic ratio of greater than 25:1. This means that YK-11 is very weakly androgenic, and provides anabolic effects while minimizing the negative effects on the prostate and other organs. YK-11 appears to be weakly suppressive to the Hypothalamic Pituitary Testicular Axis (HPTA), but far less so than any anabolic steroids or prohormones. YK-11 users have observed no elevations in estrogen, and decreases sex hormone binding globulin (which would result in a raised free testosterone, but not total testosterone). In addition to that, YK-11 is a bit leaner than LGD-4033, and is excellent for lean gains on par with testosterone. It produces lean, dry, easily kept gains in strength and muscle, and reductions in bodyfat.