If your priority is building muscle, IGF 1 is what really matters. Recombinant expression of IGF 1 and LR3 IGF 1 fused with xylanase in Pichia pastoris Applied Microbiology and Biotechnology Springer Nature Link IGF 1LR3 1MG SSP Research IGF 1 LR3 The Muscle Building Peptide Everyone's Talking About IGF 1 LR3 is one of the most powerful performance peptides used for muscle growth, recovery, and fat loss. It's a modified version IGF 1 LR3 Injection Benefits And How It Works The HCG Institute IGF 1: Miracle Hormone or Health Hazard? Diet vs Disease