Does IGF-1 LR3 increase muscle growth?

In cell and animal studies, IGF-1 signaling drives muscle protein synthesis and supports satellite cells, the stem cells that repair muscle fibers. In mice, extra IGF-1 in muscle preserved mass and strength with age, and in rats, IGF-1 variants that bind poorly to IGF binding proteins had stronger anabolic effects than native IGF-1.

No controlled human study has tested IGF-1 LR3 on muscle or performance, so claims about muscle growth in people, including new muscle fibers, go beyond the evidence. The analog’s main research value is that it stays free of binding proteins, which makes it potent at low concentrations in culture. Read our research purposes only policy, then shop IGF 1 LR3 for cell and animal research.