Mechanisms of IGF 1 Mediated Regulation of Skeletal Muscle Hypertrophy and Atrophy IGF 1 LR3 does not promote growth in late gestation growth restricted fetal sheep American Journal of Physiology Endocrinology and Metabolism American Physiological Society HGH vs IGF 1 LR3: Scientific Comparison & Research Guide IGF LR3 is a peptide that play a role in muscle growth, tissue repair and recovery. But like all peptide therapies, it's not one size fits all. We focus on using peptides thoughtfully and in the