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ToolsCompareFollistatin vs MGF (Mechano Growth Factor)

Follistatin vs MGF (Mechano Growth Factor)

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

Anabolic & IGF
Follistatin
Anabolic & IGF
MGF (Mechano Growth Factor)
Summary
Follistatin is an endogenous glycoprotein that acts as a potent inhibitor of myostatin and activin, two proteins that limit muscle growth. By binding and neutralizing myostatin, follistatin removes the primary brake on skeletal muscle hypertrophy, enabling significant muscle growth beyond normal physiological limits. It is distinct from its isoforms Follistatin 315 and Follistatin 344 in tissue distribution and binding affinity.
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
~3–5 hours (endogenous form)
Native MGF: minutes. PEG-MGF: ~3 days
Admin Route
IM, SubQ
SubQ, IM
Research
Typical Dose
50–100 mcg per injection site
200–400 mcg
Frequency
Every other day or 2–3x per week
1–2 times per week
Key Benefits
  • Potent myostatin inhibition enabling supraphysiological muscle growth
  • Increases skeletal muscle mass and fiber size
  • May accelerate recovery from muscle injury
  • Potential benefits in muscular dystrophy and sarcopenia
  • Synergistic with IGF-1 and growth hormone in anabolic protocols
  • Animal studies show dramatic increases in muscle mass
  • Reduces muscle fibrosis in dystrophic models
  • 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
  • Potential for excessive muscle growth if doses are not controlled
  • FSH suppression with implications for fertility in women
  • Theoretical risk of cardiac hypertrophy with prolonged high-dose use
  • Limited human safety data available
  • +1 more
  • Muscle soreness (satellite cell activation)
  • Injection site irritation
  • Hypoglycemia risk (modest, less than IGF-1 LR3)
Stacks With