Follistatin 344 vs Ipamorelin

Binds and neutralizes myostatin (GDF-8) and activin; removes the natural brake on muscle growth allowing supraphysiological hypertrophy

A myostatin inhibitor that removes the natural limit on muscle growth. Produces dramatic increases in muscle mass and strength by blocking TGF-β family proteins.

Ipamorelin binds to the ghrelin receptor (GHSR-1a) and stimulates dose-dependent GH release with a clean hormonal profile. Unlike GHRP-6 or hexarelin, it does not significantly stimulate appetite-related pathways or cortisol secretion at standard research doses. This selectivity makes it a frequently studied peptide for protocols where hormonal side-effect profiles are a consideration.

Ipamorelin is a selective growth hormone secretagogue and ghrelin receptor agonist. It stimulates pulsatile GH release from the anterior pituitary with high selectivity — producing minimal effect on cortisol, prolactin, or ACTH compared to earlier GHRPs. It is commonly researched for its role in supporting body composition, recovery, and lean mass maintenance.