IGF-1 LR3 (Insulin-like Growth Factor-1 Long R3) — IGF-1 LR3 is a synthetic analog of Insulin-like Growth Factor-1 (IGF-1), an 83-amino acid peptide engineered for enhanced potency and significantly extended bioavailability compared to naturally occurring IGF-1. Through two key structural modifications — an arginine substitution at position 3 and an additional 13-amino acid N-terminal extension — IGF-1 LR3 resists binding to IGF-binding proteins in the bloodstream, allowing it to remain active for up to 20–30 hours and deliver more sustained anabolic signaling to target tissues.
IGF-1 is a hormone produced primarily by the liver in response to growth hormone stimulation and plays a central role in cell growth, tissue repair, and metabolic regulation throughout adulthood. Its synthetic long-chain variant amplifies these effects with greater consistency and duration.
Clinical Applications
- Lean muscle development and preservation (including sarcopenia support)
- Accelerated tissue repair and post-injury recovery
- Enhanced metabolic function and fat utilization
- Bone density support via direct action on osteoblasts
- Improved insulin sensitivity and glucose metabolism
- Cognitive support in the context of growth hormone deficiency
How It Works IGF-1 LR3 binds to IGF-1 receptors on muscle, bone, and other tissue cells, activating the PI3K/Akt/mTOR signaling pathway. This triggers both hypertrophy (increased cell size) and hyperplasia (new cell formation), supporting muscle development through dual mechanisms.
For use under physician supervision only. Prescription and provider consultation required. Individual results vary.
