S-23

S23 is one of the existing SARMs currently under development. Sarm S-23 increases the amount of muscle energy, accelerates the reduction of fat consumption, is a sarm with a very strong binding affinity to androgen receptors, therefore it is stronger than Ostarine or Andarine S-4.

S23 is becoming increasingly popular in the recreational bodybuilding community due to its powerful muscle building and body recomposition effects. Recreational users are quickly identifying S23 as a stronger alternative to S4 (S-4), without the side effect of night vision. S23 has also been shown in studies to reduce prostate size, which is the opposite of a very common negative side effect of anabolic steroids (prostate enlargement). However, this data is often misinterpreted because all SARMs prevent prostate enlargement in a dose-dependent manner, which was discussed in detail in the study.

S23 has a very high binding affinity to the androgen receptor (AR) with a Ki of ~1.7 nM. Ki is the equilibrium dissociation constant defined kinetically as the ratio of the rate constants koff/kon of substrate binding to the androgen receptor. In layman's terms, the lower the Ki value, the greater the binding affinity to the androgen receptor. For comparison, RAD-140 (RAD140) has a Ki value of 7 nM. S23 has a binding affinity more than four times higher than RAD140, which was already considered impressive.

S-23 is a very strong sarm recommended for advanced athletes and should not be used by people under 21 years of age.

Dosage

10-20mg daily