IGF-1 LR3
IGF-1 LR3
Also known as: Long R3 IGF-1, LR3-IGF-1, IGF-1 Long R3
Overview
Key Facts
Primary Goal: Research and therapeutic applications of IGF-1 LR3
Binds IGF-1 receptor (IGF-1R) with similar affinity to native IGF-1 but with greatly reduced IGFBP binding. Activates PI3K/Akt/mTOR cascade driving protein synthesis and cell growth.
Dosing Information
and greater bioavailability than native IGF-1. It is one of the most potent peptides for promoting skeletal muscle hypertrophy and hyperplasia.Half-Life20-30 hours
20–100 mcg
Once daily, often post-workout on training days
4-6 weeks on, 2-4 weeks off
Benefits
- Potent stimulation of muscle protein synthesis via mTOR pathway
- Promotes muscle cell hyperplasia (new muscle cell formation)
- Enhanced nitrogen retention and nutrient partitioning
- Accelerated recovery between training sessions
- Supports connective tissue and cartilage repair
- Anti-catabolic effects during caloric deficit
Side Effects
Mechanism of Action
Binds IGF-1 receptor (IGF-1R) with similar affinity to native IGF-1 but with greatly reduced IGFBP binding
Activates PI3K/Akt/mTOR cascade driving protein synthesis and cell growth
Stimulates satellite cell proliferation and differentiation (hyperplasia)
Activates MAPK/ERK pathway promoting cell survival and proliferation
Cross-reacts with insulin receptor at high concentrations (hypoglycemia risk)
Contraindications
Do not use this peptide if any of the following apply:
- Active or history of any malignancy (potent growth factor)
- Diabetes or hypoglycemia-prone conditions
- Pregnancy or breastfeeding
- Diabetic retinopathy
- Under 25 years of age (open growth plates risk)
Storage & Reconstitution
Unreconstituted (Powder)
Reconstituted (Mixed)
Research Summary
IGF-1 LR3 has been widely studied in cell culture and animal models, demonstrating potent anabolic effects. Studies show 2-3x greater potency than native IGF-1 in stimulating muscle protein synthesis due to reduced IGFBP sequestration. Research in livestock has shown significant increases in lean mass. While no formal clinical trials exist for the LR3 variant, native IGF-1 (mecasermin) is FDA-approved for growth failure, establishing the pathway's clinical validity.
Frequently Asked Questions
Common questions about IGF-1 LR3
UK-Specific Information
Exclusive data points and guidance for UK residents using IGF-1 LR3
UK Lab Testing
UK Lab Testing
Recommended labs: Medichecks, Thriva (£89-£149 for peptide safety panel)
Why this matters: UK-specific lab testing guidance not available on US competitor sites
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Note: Peptide stacking should only be done under the guidance of a qualified healthcare professional. Individual responses may vary.
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