IGF 1LR3 Histochemical and IF studies of IGF 1 in skeletal muscle. ( a ) Download Scientific Diagram Localized Igf 1 transgene expression sustains hypertrophy and regeneration in senescent skeletal muscle Nature Genetics GH IGF 1 Abnormalities and Muscle Impairment: From Basic Research to Clinical Practice Discover IGF 1 (Insulin like Growth Factor 1), a key player in muscle development and overall growth! This essential peptide stimulates protein synthesis, helping to build lean muscle mass and enhance recovery after workouts.