IG 1 Peptide Research Grade Beyond Peptides Chapter 2 Parliament of Australia 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 The Therapeutic Goods Administration has issued a safety warning, saying it's "concerned" about an increase in the importation and supply of unapproved peptides.