LONG R IGF I IGF 1 LR3 Dosage Calculator and Chart A Z Guide IGF 1 LR3 The Muscle Building Peptide Everyones Talking About , IGF 1 LR3 is one of the most powerful performance peptides used for muscle growth, recovery, and fat loss. Its a modified version IGF 1 LR3 Research Overview IGF 1 LR3 is a modified insulin like growth factor analog currently being studied for its interaction with IGF 1 receptor pathways. Research has focused on its role in cellular LONG R IGF I RUO Recombinant Human IGF 1 LR3 Protein