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 HGH vs IGF 1 LR3: Scientific Comparison & Research Guide Attenuated glucose stimulated insulin secretion during an acute IGF 1 LR3 infusion into fetal sheep does not persist in isolated islets Journal of Developmental Origins of Health and Disease Cambridge Core IGF 1 LR3 does not promote growth in late gestation growth restricted fetal sheep American Journal of Physiology Endocrinology and Metabolism American Physiological Society Explanation, Benefits, and Dosing for IGF LR3 Wittmer Rejuvenation Clinic IGF 1 LR3 does not promote growth in late gestation growth restricted fetal sheep American Journal of Physiology Endocrinology and Metabolism American Physiological Society