Human insulin IGF 1 and familial longevity at middle age Aging Mechanisms of IGF 1 Mediated Regulation of Skeletal Muscle Hypertrophy and Atrophy IGF 1 LR3 The Muscle Building Peptide Everyone's Talking About IGF 1 LR3 is one of the most powerful performance peptides used for muscle growth, recovery, and fat loss. It's a modified version 40 YEARS OF IGF1: Insulin like growth factors: actions on the skeleton in: Journal of Molecular Endocrinology Volume 61 Issue 1 (2018)