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 Follow for more info on how to optimize your body. IGF 1 LR3 is one of the most misunderstood compounds in the entire space. People either treat it like a magic shortcut or I am injecting IGF 1 LR3 to myself. I have experienced some side effects that I want to reduce to zero. If you have injected IGF 1 or have any other experience with intramuscular HGH vs IGF 1 LR3: Scientific Comparison & Research Guide