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IGF-1 LR3
PerformanceSingleAlso known as: Long R3 IGF-1, Insulin-Like Growth Factor-1 Long Arginine 3
A long-acting analog of insulin-like growth factor-1 with greatly extended half-life compared to native IGF-1, studied for muscle growth contexts.
Half-life
20 h
Common dose
20 – 80 mcg
Dosing frequency
Daily
Administration
Subcutaneous
How it works
IGF-1 binds the IGF-1 receptor, driving protein synthesis, hyperplasia, and nutrient partitioning. The LR3 modification reduces binding to IGF-binding proteins, extending its half-life from minutes to ~20 hours.
Protocol notes
Research dosing is 20–80 mcg daily subcutaneously, often pre- or post-workout. Cycles of 4–6 weeks are typical, separated by equal time off. Carries hypoglycemia risk.
Reported side effects
Hypoglycemia, lethargy, organ growth concerns with long-term use, injection-site reactions, water retention.