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This is plain-language harm-reduction information, not medical advice. Peptides discussed here are research compounds; most are not approved for human use. People will use them either way — we would rather they have the facts.
What it is
MGF (mechano growth factor) is a splice variant of IGF-1 that the body produces in response to muscle damage — it is part of the signal that recruits satellite cells (the cells that repair and grow muscle).
PEG-MGF has polyethylene glycol attached to extend its half-life from minutes to days.
History
Discovered as a distinct IGF-1 variant in the 1990s by Geoffrey Goldspink.
How it works
Activates muscle satellite cells, which fuse with damaged muscle fibres to repair and grow them.
Dosage
- 200–500 mcg post-workout, 2–3 times per week.
How it is taken
- Subcutaneous or intramuscular injection within 30–60 minutes post-workout.
How to reconstitute
- 2 mg vial with 2 ml BAC water = 1 mg/ml. 250 mcg = 25 units on a 1 ml insulin syringe.
How it should arrive
White powder, sealed vial.
How it should look once reconstituted
Clear colourless solution.
What to expect, and when
- Body composition changes: 4–8 weeks of consistent use.
Side effects
- Pump and warmth at injection site.
- Occasional fatigue.
- Theoretical IGF-1-like side effects, though less pronounced than IGF-1 LR3.
Risks
- Theoretical IGF-1 cancer-promotion concern (less than full IGF-1 LR3).
- WADA prohibited.
Potential gains
- Improved muscle recovery and growth response post-training.
Other useful information
Less aggressive than IGF-1 LR3 because its action is timed to actual muscle damage. Reasonable choice if you want to support recovery without the full IGF-1 LR3 risk profile.
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