IGF-1 lr3 is an anabolic peptide commonly use to increase metabolism, promote protein synthesis, and help bodybuilders gain muscle mass. So, obviously, IGF-1 lr3 makes you bigger. Not only that, IGF-1 stimulate testosterone production in testicular interstitial cells and, together with testosterone, mediate some of the growth-promoting effects of androgens in androgen-reactive tissues. So, in addition to building muscle, IGF-1 …