IGF-1 LR3 is an insulin growth factor and variant of IGF-1. IGF-1 Lr3  is a synthetic protein that stimulate cell growth, muscle growth , increased bone density, tissue strengthening. IGF has an extended amino acid chain (83 vs 70 amino acids in natural IGF-1), giving it a longer half life in the body and  the substitution of an arginine at the 3rd position reduces its binding to IGF binding proteins (IGFBPs), making it more bioavailable. IGF enhances protein synthesis and muscle hypertrophy. Accelerates healing of muscles, tendons, and connective tissues. Improves nutrient uptake, encouraging lean gains. Potent anabolic activity, often stronger than HGH itself.