IGF-1 LR3
Extended half-life insulin-like growth factor for muscle research
Key Research Areas
Researched for muscle growth mechanisms
Studied for enhanced protein synthesis
Investigated for recovery and regeneration
What is IGF-1 LR3?
IGF-1 LR3 is a synthetic, modified version of human Insulin-like Growth Factor-1 (IGF-1). The "LR3" designation refers to specific modifications: an arginine substitution at position 3 and a 13-amino acid extension at the N-terminus. These modifications prevent IGF-1 LR3 from binding to IGF binding proteins (IGFBPs), which normally limit IGF-1 activity. This results in a much longer half-life and greater bioavailability compared to standard IGF-1.
What It's Used For
Research focuses on muscle hypertrophy (growth) mechanisms, protein synthesis pathways, cell proliferation and differentiation, tissue repair and regeneration, and metabolic effects. IGF-1 LR3 is particularly studied in contexts related to muscle development and recovery due to its potent anabolic properties.
How It Works (Mechanisms Explained)
IGF-1 LR3 binds to the IGF-1 receptor (IGF-1R) on cell surfaces, triggering intracellular signaling cascades. This activates the PI3K/Akt pathway, which promotes protein synthesis and inhibits protein breakdown. It also activates the MAPK pathway, stimulating cell proliferation. Because it does not bind to IGFBPs, more of the peptide remains active in circulation, leading to stronger and more prolonged effects than native IGF-1.
Common Research Stacks
In research settings, IGF-1 LR3 is sometimes studied alongside growth hormone secretagogues (like CJC-1295 or Ipamorelin) or other anabolic compounds. The timing of administration relative to meals and exercise is often a focus of research protocols due to interactions with insulin.
Common Beginner Mistakes
Not understanding its potency compared to regular IGF-1 (much stronger effects), improper timing of administration, neglecting the importance of proper nutrition and training when studying anabolic effects, hypoglycemia risk (IGF-1 can lower blood sugar), and sourcing issues with peptide quality.
Reconstitution Basics
IGF-1 LR3 comes as a lyophilized powder and is typically reconstituted with bacteriostatic water or acetic acid solution (some protocols use 0.6% acetic acid for stability). Add liquid slowly along the vial wall and swirl gently. Once reconstituted, refrigerate and use within 28 days. Administration is typically subcutaneous or intramuscular depending on the research protocol.
Educational Disclaimer
This content is for educational purposes only and is not intended as medical advice. Research peptides are not approved for human use by regulatory bodies like the FDA. Always consult qualified healthcare professionals before making any health-related decisions.