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ToolsCompareFollistatin 344 vs PEG-MGF

Follistatin 344 vs PEG-MGF

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

Anabolic & IGF
Follistatin 344
Anabolic & IGF
PEG-MGF
Summary
Follistatin 344 is a recombinant form of the endogenous follistatin protein. It inhibits myostatin and activin — the primary negative regulators of muscle growth — potentially removing the genetic ceiling on muscle development. It is one of the most theoretically powerful anabolic compounds but is experimental with limited human data.
PEG-MGF (Pegylated Mechano Growth Factor) is a modified form of MGF (Mechano Growth Factor) where polyethylene glycol (PEG) chains have been attached to extend its half-life from minutes to days. Native MGF is released locally in muscle in response to mechanical stress and quickly degrades. PEGylation allows systemic administration with sustained circulation, enabling whole-body muscle repair and anabolic signaling rather than the purely local effect of native MGF.
Half-Life
~24–36 hours
~3 days (due to PEGylation)
Admin Route
SubQ, IM
SubQ
Research
Typical Dose
100 mcg
200–400 mcg
Frequency
Once daily
2–3x per week
Key Benefits
  • Inhibits myostatin — removes muscle growth ceiling
  • Significant increases in muscle mass and strength
  • Reduces fat mass
  • Promotes bone density
  • May stimulate hair follicle cycling
  • Anti-fibrotic effects in muscle tissue
  • Synergistic with IGF-1 and other anabolic peptides
  • Extended half-life (~3 days) vs native MGF (minutes)
  • Systemic muscle satellite cell activation via subcutaneous injection
  • Promotes muscle fiber repair and hypertrophy throughout the body
  • Enhanced recovery from intense training or muscle injury
  • Synergistic with IGF-1 LR3 and growth hormone peptides
  • Useful in sarcopenia, post-injury recovery, and athletic performance
  • Single injection provides multi-day anabolic signaling
Side Effects
  • Muscle soreness (from rapid hypertrophy)
  • Potential reproductive effects (activin inhibition)
  • Unknown long-term safety profile
  • Possible esophageal effects at high doses (animal data)
  • Water retention and localized swelling
  • Potential hypoglycemia at high doses
  • Theoretical cancer growth risk (growth factor)
  • Injection site reactions
  • +1 more
Stacks With