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ToolsCompareIGF-1 LR3 vs MGF (Mechano Growth Factor)

IGF-1 LR3 vs MGF (Mechano Growth Factor)

Side-by-side comparison of key properties, dosing, and research.

Anabolic & IGF
IGF-1 LR3
Anabolic & IGF
MGF (Mechano Growth Factor)
Summary
IGF-1 LR3 is a synthetic analog of Insulin-like Growth Factor-1 with an extended half-life. It is one of the most potent anabolic peptides available, directly stimulating muscle cell hyperplasia and hypertrophy, and is the downstream mediator of many of GH's anabolic effects.
MGF (Mechano Growth Factor) is a splice variant of IGF-1 that is locally produced in muscle tissue in response to mechanical damage from exercise. It activates muscle satellite cells (stem cells) to proliferate and repair damaged fibers, making it specifically targeted at exercise-induced hypertrophy.
Half-Life
20–30 hours
Native MGF: minutes. PEG-MGF: ~3 days
Admin Route
SubQ, IM
SubQ, IM
Research
Typical Dose
40–80 mcg
200–400 mcg
Frequency
Once daily or split twice daily
1–2 times per week
Key Benefits
  • Direct muscle hypertrophy via IGF-1R stimulation
  • Muscle hyperplasia (new fiber formation) — unique among peptides
  • Rapid gains in lean muscle mass
  • Accelerated recovery from training and injury
  • Increased nutrient uptake by muscle cells
  • Fat oxidation enhancement
  • Bone density improvement
  • Cartilage and connective tissue repair
  • Activates muscle satellite cells for repair and growth
  • Accelerates recovery from muscle damage
  • Synergistic with IGF-1 LR3 (different mechanisms)
  • Promotes muscle hypertrophy specifically at exercised muscles
  • Faster recovery between training sessions
  • Potential for injury repair in connective tissue
Side Effects
  • Hypoglycemia (significant risk — insulin-like activity)
  • Acromegaly-like effects with excessive long-term use
  • Jaw and hand swelling
  • Organ hypertrophy with extreme doses
  • +2 more
  • Muscle soreness (satellite cell activation)
  • Injection site irritation
  • Hypoglycemia risk (modest, less than IGF-1 LR3)
Stacks With