If your goal is better body composition, that means more muscle and less fat, certain peptides can help. These are not steroids and they do not replace testosterone if testosterone is low. 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 Effects of IGF1 isoforms on muscle growth and sarcopenia Ascenzi 2019 Aging Cell Wiley Online Library IGF 1, the Cross Road of the Nutritional, Inflammatory and Hormonal Pathways to Frailty