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Muscle & Growth Hormone

PEG-MGF

PEGylated Mechano Growth Factor · IGF-1Ec
experimentalnichesubQ injection

What it is

PEG-MGF is a PEGylated (polyethylene-glycol-modified) version of MGF (Mechano Growth Factor). MGF is a splice variant of IGF-1 that's released after muscle damage. The PEG attachment dramatically extends MGF's natural ~5 minute half-life to several days.

How it works

Activates muscle satellite cells — the dormant stem cells responsible for muscle repair and hypertrophy. Theoretically helps recruit new muscle nuclei to support long-term muscle growth.

Benefits

Timeline

Week 1–2
Subtle — reports vary widely.
Week 4–6
Some users report better recovery.
Week 6–8
End of cycle. Real-world results often disappointing.

Dosing & titration

Standard dose200–400 mcg subQ, 1–2x per week
Cycle length6–8 weeks ON, 4 weeks OFF
TimingPost-workout
When to titrate upIncreasing rarely changes results — this peptide's effect is theoretical more than practical for most users.

Side effects & risks

Theory strong, real-world evidence weak. Most experienced users see better results from IGF-1 LR3 if going down this pathway.

Typical price

$80–$150/mo2 mg vial from a 503A compounding pharmacy.

Studies

Educational reference only. Not medical advice.