IGF 1 LR3 and Penis Enlargement: What the Evidence Actually Shows IGF 1 LR3 tells your muscle cells to grow, repair, and absorb nutrients better. It works directly at the muscle level to help you build lean muscle and recover faster.What it is IGF 1 IGF 1 Therapy Improves Muscle Size and Function in Experimental Peripheral Arterial Disease ScienceDirect IGF 1 LR3 does not promote growth in late gestation growth restricted fetal sheep American Journal of Physiology Endocrinology and Metabolism American Physiological Society IGF 1 LR3 Injection Benefits And How It Works The HCG Institute IPA CJC IGF BLEND Beverly Hills Rejuvenation Center