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 LONG R IGF I Muscles are most sensitive to growth signals after training. IGF 1 LR3 drives nutrients into muscle cells, boosts protein synthesis and recovery. Triggers muscle growth pathways, and helps nutrients IGF 1 LR3 1MG Beverly Hills Rejuvenation Center Insulin like Growth Factor I Extends in VitroReplicative Life Span of Skeletal Muscle Satellite Cells by Enhancing G1 S Cell Cycle Progression via the Activation of Phosphatidylinositol 3 Kinase Akt Signaling Pathway ScienceDirect Insulin like Growth Factor I Extends in VitroReplicative Life Span of Skeletal Muscle Satellite Cells by Enhancing G1 S Cell Cycle Progression via the Activation of Phosphatidylinositol 3 Kinase Akt Signaling Pathway ScienceDirect