Switched things up and have been using my IGF 1 LR3 30 mins pre workout and have been noticing longer lasting pumps and more vascularity so far! 2 more weeks until I cycle 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, IGF 1 LR3 does not promote growth in late gestation growth restricted fetal sheep American Journal of Physiology Endocrinology and Metabolism American Physiological Society Receptor Grade IGF 1 LR3 1MG Raw Amino DopeRX IGF 1 LR3 at Attractive Prices Top Peptide for Muscle Growth