IGF-1 LR3 – is a long-acting synthetic analogue of insulin-like growth factor-1 designed for extended bioactivity. By resisting binding to IGF-1 binding proteins, it remains active up to 120 times longer than native IGF-1. Research suggests it may enhance muscle repair and hypertrophy, promote cell growth, improve fat metabolism, and inhibit myostatin, with additional studies exploring lactation support.