Ostarine (MK‑2866 / Enobosarm) is an orally active, non-steroidal Selective Androgen Receptor Modulator (SARM) that binds selectively to androgen receptors (AR) in skeletal muscle and bone tissue. By mimicking the effects of endogenous testosterone, Ostarine activates anabolic signaling pathways that stimulate protein synthesis, promote lean muscle hypertrophy, increase strength, and enhance bone density, while minimizing androgenic activity in non-target tissues such as the prostate and liver. Ostarine supports fat metabolism and body composition by enhancing muscular energy utilization and promoting favorable shifts in muscle-to-fat ratio. It also contributes to accelerated recovery from muscle stress or injury by regulating gene expression involved in tissue repair, protein turnover, and cellular metabolism. Its selective receptor modulation allows users to experience many of the performance and aesthetic benefits of anabolic steroids without the systemic side effects typically associated with steroid use. Additionally, preliminary studies suggest Ostarine may aid in preserving lean muscle mass during periods of caloric deficit, supporting both endurance and overall metabolic health.