Pegylated Mechano Growth Factor (PEG MGF) is a variant of the IGF-1 (insulin-like growth factor-1), which stimulates myoblasts division and allows for muscle fibers to fuse and mature. This is a process required for growth of adult muscle. The difference between IGF-1 and MGF is that MGF stimulate myoblasts division through stimulation of different receptors.
Pegylated MGF is more bioavailable. Injected 2-3 times per week, it maintains effective concentration for a long period.