Peptide Library / Advanced / Growth
IGF-1 LR3
Also known as: Long-R3 insulin-like growth factor 1
A long-acting version of the body's primary growth signal — the compound experienced researchers graduate to once the GH-axis pair has done its work.
| Typical research dose | 20–50 mcg |
|---|---|
| Frequency | 1× daily (training days, post-workout is common) |
| Route | Subcutaneous or intramuscular injection |
| Cycle length | 4 weeks maximum, then equal or longer break |
Figures reflect protocols commonly reported in the research community — not a prescription or a recommendation.
What it is
IGF-1 is the hormone that actually executes most of what "growth hormone" gets credit for — GH tells your liver to make IGF-1, and IGF-1 drives the tissue growth. LR3 is a modified version engineered to last far longer in circulation (hours instead of minutes) by dodging the binding proteins that normally soak it up. That makes it much more potent — and much less forgiving — than the GH-axis peptides (CJC-1295, Ipamorelin), which merely ask your body to make its own.
What the research looks at
- Muscle growth — direct anabolic signaling: increased protein synthesis and, in animal models, new muscle-cell formation (hyperplasia).
- Recovery and tissue repair — connective tissue and muscle repair models.
- Nerve and gut research — smaller preclinical lanes.
How protocols are commonly structured
Research-community protocols run 20–50 mcg once daily, often post-training, for no more than ~4 weeks before a break (receptor desensitization is the cited reason). Two protocol habits define experienced use: time doses around a carbohydrate-containing meal (IGF-1 moves blood sugar insulin-style, and carbs are the standard companion), and run the GH-axis pair first — this is the graduate compound, not the entry point.
Reconstitution & storage
Lyophilized powder — note many suppliers ship IGF-1 LR3 requiring acetic acid or specialized diluent rather than plain bacteriostatic water; follow the COA / supplier data sheet for the correct diluent. Refrigerate after mixing; fragile molecule, no shaking.
Research protocols, not a prescription — talk to a physician before touching anything.