IGF-1 LR3 is a peptide hormone which is made naturally in the body from growth hormone and which, like growth hormone, has a number of physiological effects including increasing muscle mass, reducing fat mass, and inducing vasodilation. It stands for insulin-like growth factor and as with insulin, IGF-1 LR3 is considered a very anabolic compound although its effects are quite different to those of insulin itself. The LR3 version of IGF-1 is resistant to breakdown making it more physiologically active than the short form version of IGF-1. Clinically, IGF-1 LR3 is rarely used outside of some anti-aging doctors.
Off Label - Currently, the use of IGF-1 LR3 has been seen predominantly among bodybuilders and athletes seeking to increase their level of muscularity, reducing their fat mass, and enhancing performance and recovery.
It has been mooted that among its anabolic properties, IGF-1 LR3 is capable of inducing skeletal muscle hyperplasia, the process by which satellite muscle fibres are converted into new muscle fibres. Theoretically, this means an individual using IGF-1 LR3 would be capable of holding a higher degree of muscle mass.
While mainly used by male bodybuilders, both men and women can use IGF-1 LR3. Indeed, for women it represents one of a small number of muscle building compounds that will work without causing masculinizing effects in the way steroids would do.
Users of IGF-1 LR3 typically use it in short "cycles" of around 2-4 weeks. It is commonly noted that its effects tend to dissipate at this time with many users waiting a period of 2 months before embarking on its use again.