GLP 1 Drugs Could Raise the Risk of Weaker Bones and Gout IGF 1 LR3 is a powerful growth factor that helps build muscle, burn fat, and speed up recovery. It works by boosting protein synthesis, which helps muscles grow and heal faster. It also improves how What is IGF 1 LR3?, Insulin Like Growth Factor 1 Long R3 (IGF 1 LR3) is a modified version of IGF 1 with a longer half life, making it significantly more potent and effective for muscle growth, LONG R IGF I IGF 1LR3 IGF 1 LR3 Peptide Guide: Effects, Risks & Alternatives (2026)