CJC 1295 + Ipamorelin vs IGF 1 LR3 for Muscle Growth IGF 1 LR3 forces receptor desensitization in 4 6 weeks, requiring months off before you can use it again. CJC 1295 and Ipamorelin amplify your natural LONG R IGF I Insulin Like Growth Factor 1 (IGF 1) Physiopedia 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 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 LONG R IGF I