New — Free Peptide Starter Guide (2026): 13 chapters, 34 cited studies

Get it free
ToolsCompareMGF (Mechano Growth Factor) vs Somatropin (HGH)

MGF (Mechano Growth Factor) vs Somatropin (HGH)

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

Anabolic & IGF
MGF (Mechano Growth Factor)
Growth Hormone PeptidesAnti-Aging & Longevity
Somatropin (HGH)
Summary
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.
Somatropin is recombinant human growth hormone (rhGH), identical in structure to the 191-amino acid pituitary-derived growth hormone. It is FDA-approved for growth hormone deficiency, short stature, and wasting conditions. Off-label, it is widely explored for body composition, anti-aging, and performance enhancement, though significant risks accompany unsupervised use.
Half-Life
Native MGF: minutes. PEG-MGF: ~3 days
2-3 hours (subcutaneous); 20-30 minutes (intravenous)
Admin Route
SubQ, IM
Subcutaneous, Intramuscular (less common)
Research
Typical Dose
200–400 mcg
0.15-0.3 mg/day (adults); titrated to IGF-1 levels
Frequency
1–2 times per week
Once daily
Key Benefits
  • 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
  • Increases lean muscle mass and reduces body fat (particularly visceral)
  • Restores growth hormone deficiency (FDA-approved)
  • Improves bone mineral density
  • Enhances exercise capacity and recovery
  • Supports skin thickness and collagen synthesis
  • Improves lipid profile in GHD patients
  • Explored for anti-aging and cellular regeneration
Side Effects
  • Muscle soreness (satellite cell activation)
  • Injection site irritation
  • Hypoglycemia risk (modest, less than IGF-1 LR3)
  • Fluid retention and edema (common, dose-dependent)
  • Carpal tunnel syndrome
  • Joint and muscle pain
  • Insulin resistance and elevated blood glucose
  • +3 more
Stacks With