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MGF Guide: Available Now
Educational use only — not medical advice. This guide summarizes information reported in published research and community practice for educational purposes. It is not medical advice and not a recommendation to use any compound. Any doses, schedules, or combinations shown are examples of what has been reported, not instructions for you. Many peptides described here are research compounds that are not FDA-approved for the uses discussed and may be investigational or restricted. Effects, risks, and legal status vary; individual needs and results vary. Consult a qualified, licensed healthcare professional before making any decision. Do not use this content to diagnose, treat, or dose yourself.
MGF at a glance
What it is
A locally-acting splice variant of IGF-1 (IGF-1Ec / the MGF E-domain peptide); PEG-MGF is the pegylated, longer-lasting form
Researched for
Satellite (muscle stem) cell activation, muscle repair and hypertrophy signaling in preclinical/animal studies
Commonly reported range
200–400 mcg per injection (community reports span roughly 100–600 mcg)
Route reported
Native MGF: local intramuscular into the trained muscle. PEG-MGF: subcutaneous or intramuscular
Reported frequency
PEG-MGF ~1–3x/week; native MGF post-workout on training days only
Reported cycle
Commonly 4–8 weeks in community protocols
Plasma half-life
Native MGF ~5–7 minutes; PEG-MGF reported ~48–72 hours (some sources cite up to ~5 days)
Regulatory status
Not FDA-approved; research-use-only; prohibited by WADA under Section S2
Reported ranges from research/community — examples, not recommendations.
What it is / mechanism
MGF (mechano growth factor) is a splice variant of insulin-like growth factor 1, formally IGF-1Ec, produced locally by skeletal muscle in response to mechanical loading or tissue damage. A reading-frame shift in the IGF-1 gene's E-domain produces a unique C-terminal peptide that appears to act as an autocrine/paracrine signal at the site of muscle stress rather than as a systemic hormone. Research by Yang and Goldspink (2002) reported that the MGF E-domain peptide can drive muscle satellite (stem) cells into the cell cycle and promote their proliferation in a manner not blocked by IGF-1 receptor antibodies, suggesting a distinct or co-receptor interaction rather than pure IGF-1R signaling. In the commonly described model, MGF first expands the satellite cell pool while systemic IGF-1 (or IGF-1 LR3) later drives differentiation and protein synthesis. Native MGF is degraded within minutes, so PEG-MGF attaches a polyethylene-glycol chain to slow clearance and extend activity for more practical dosing intervals.
Researched effects
In preclinical and animal research, MGF and PEG-MGF have been associated with activation and proliferation of muscle satellite cells, accelerated muscle repair after damage, and support for hypertrophy signaling; some studies also explored neuroprotective and cardiac-repair contexts. Community reports describe faster perceived recovery and localized muscle response, but these are anecdotal and not controlled outcomes. These are research findings, not guaranteed outcomes: human clinical evidence is very limited, no controlled efficacy trials support performance or physique claims, and individual responses are unknown.
Evidence & regulatory status
Evidence: mechanistic and animal studies (e.g., Yang & Goldspink) report satellite-cell activation and muscle-repair signaling by the MGF E-domain peptide; no completed controlled human efficacy trials for muscle growth are on record as of 2026.
Regulatory: MGF and PEG-MGF are not approved by the FDA (or any regulator) for any use, and both are explicitly prohibited by the World Anti-Doping Agency under Section S2 (peptide hormones, growth factors, related substances).
Research-use: material sold as MGF/PEG-MGF is intended for laboratory research only, not for human consumption, and any use described here is reported behavior, not a recommendation.
Dosage — reported ranges (overview)
These are examples of what is reported in community and research-chemical contexts, not a recommendation and not a personal dose. Reported per-injection amounts most commonly cluster around 200–400 mcg, with the wider community range spanning roughly 100–600 mcg. Native MGF is typically described as injected locally into the muscle trained that session, within minutes of the workout, because of its extremely short half-life. PEG-MGF, being longer-acting, is reported as subcutaneous or intramuscular roughly 1–3 times per week, timed less strictly. Reported cycles tend to run 4–8 weeks. None of this establishes safety or a correct dose for any individual.
The full step-by-step protocol examples, titration, and printable protocol sheet are planned for a future paid Protocol Playbook module.
Reconstitution — bac-water math
Reconstitution is concentration math only, not a personal dose. MGF/PEG-MGF is dosed in micrograms (mcg), so on a U-100 insulin syringe the concentration in mcg/mL is (vial mg × 1000) ÷ mL of bacteriostatic water, and the units to draw for a target dose D (mcg) are round(D ÷ concentration × 100). Worked example with a representative 2 mg vial: adding 2 mL of bacteriostatic water gives (2 × 1000) ÷ 2 = 1000 mcg/mL. A 200 mcg example draw is 200 ÷ 1000 × 100 = 20 units on a U-100 syringe; a 400 mcg example draw is 40 units. Always add water slowly against the vial wall and swirl gently rather than shaking.
Bac water added
Concentration
200 mcg
400 mcg
1 mL
2000 mcg/mL (2 mg/mL)
10 units (0.10 mL)
20 units (0.20 mL)
2 mL
1000 mcg/mL (1 mg/mL)
20 units (0.20 mL)
40 units (0.40 mL)
3 mL
667 mcg/mL (0.67 mg/mL)
30 units (0.30 mL)
60 units (0.60 mL)
This is concentration math, not a dose recommendation.
Pre-fills example values. Every field remains editable.
The amount printed on the vial or listed on a product page.
mL
Liquid volume used for the concentration calculation.
The mass amount to convert into liquid volume for this math example.
4. Insulin syringe size
Your result
Syringe-unit reading
10 units
= 0.1 mL · 250 mcg target amount
Concentration
2.5mg/mL
Per insulin unit
25mcg
Portions per vial
20
Volume
0.1mL
This calculator is an educational tool for laboratory and research math only. The peptides referenced are research compounds not intended for human or veterinary use, and example values are not medical advice or personal-use instructions. Follow applicable research protocols and regulations.
How the calculator works
Concentration
peptide ÷ liquid
Total peptide divided by liquid volume gives the concentration per mL.
Volume
target ÷ concentration
The target mass divided by concentration gives the liquid volume.
Syringe units
volume × 100
For insulin units, 100 units equals 1 mL, so mL is multiplied by 100.
Worked example: A 5 mg vial plus 2 mL liquid creates a 2.5 mg/mL concentration. A 250 mcg target amount equals 0.1 mL, or 10 insulin units. The vial contains 20 such portions.
Frequently asked questions
How much bacteriostatic water should I enter?+
There is no single calculator-default amount. The liquid volume controls concentration: more liquid creates a less concentrated solution and a larger volume reading for the same target amount; less liquid creates a more concentrated solution and a smaller volume reading.
How do insulin syringe units relate to mL?+
For this math tool, 100 insulin units equals 1 mL, and 1 unit equals 0.01 mL. The 0.3 mL, 0.5 mL, and 1.0 mL options change capacity, not the unit-to-mL relationship.
What is the difference between mg, mcg, and units?+
Milligrams and micrograms measure peptide mass: 1 mg = 1,000 mcg. Syringe units measure liquid volume. Reconstitution math connects mass and volume by using concentration.
Does changing the liquid volume change the total peptide in the vial?+
No. The total peptide amount entered for the vial remains fixed. Changing the liquid volume only changes concentration and the resulting volume shown by the calculator.
Injection / administration basics
In reported protocols, native MGF is injected intramuscularly directly into the muscle group worked that session, typically within about 5–10 minutes post-workout to align with mechanical-loading signaling. PEG-MGF is reported as subcutaneous (abdominal fat) or intramuscular, with timing considered less critical because of its longer half-life. Bacteriostatic water is used for reconstitution; saline is avoided by some because of reported precipitation. U-100 insulin syringes are standard for these microgram-level volumes. This describes reported practice, not instructions for human use.
Half-life & frequency rationale
Native MGF has a very short plasma half-life of roughly 5–7 minutes, which is why it is described as injected locally right after training. PEG-MGF's polyethylene-glycol conjugation slows clearance substantially; reported figures vary by source, most commonly cited as about 48–72 hours, with some sources estimating up to roughly 5 days. This extended duration is the rationale for the less frequent PEG-MGF dosing seen in community protocols.
Side effects, safety & contraindications
Human safety data are very limited, so reported side effects come largely from community logs and theoretical concerns rather than controlled trials. Commonly reported effects are mild and local: injection-site discomfort, redness, or swelling, and occasional headache, fatigue, dizziness, or nausea (more often at higher amounts). Because growth-factor pathways promote cell proliferation, a theoretical concern raised in the literature is that stimulating these pathways could be undesirable in the presence of existing or occult malignancy; this is a caution, not a demonstrated outcome. The absence of controlled human studies means long-term safety is genuinely unknown.
Stacking — overview
In community and research discussion, MGF/PEG-MGF is most often described alongside other recovery and growth-signaling peptides. A recurring theme is sequencing MGF with IGF-1 LR3 rather than dosing them together: MGF first to expand the satellite-cell pool, then IGF-1 LR3 hours later to drive differentiation, since simultaneous exposure is thought to blunt the effect. It is also frequently co-reported with tissue-repair peptides. These are commonly reported pairings for context, not recommendations, and all carry the same lack of human safety data.
Sequential growth-factor stack
PEG-MGF then IGF-1 LR3 (separated by several hours)
Recovery/repair stack
PEG-MGF + BPC-157 + TB-500
GH-axis support stack
PEG-MGF + CJC-1295 + Ipamorelin
Storage & handling
Lyophilized (powder): store sealed and protected from light; refrigerate at 2–8°C for long-term stability, and keep frozen for extended storage per supplier guidance.
Reconstituted (in bacteriostatic water): keep refrigerated at 2–8°C, protect from light, avoid shaking, and use within roughly 28 days as commonly advised.
References
Content synthesizes peer-reviewed mechanistic and animal research (e.g., Yang & Goldspink on the MGF E-domain and satellite-cell activation) alongside publicly available peptide reference summaries and WADA prohibited-list documentation; it is educational and not a substitute for professional medical guidance.
Related peptide guides
Continue exploring related educational guide topics in the Medibact library.
Quick answers about guide scope, access, and educational use context.
What is the difference between MGF and PEG-MGF?
MGF (mechano growth factor, IGF-1Ec) is the native peptide with a half-life of only about 5–7 minutes, so it is described as injected locally into the trained muscle right after a workout. PEG-MGF adds a polyethylene-glycol chain that extends the half-life to roughly 48–72 hours, allowing less frequent, more systemic dosing in reported protocols.
Is MGF or PEG-MGF FDA-approved?
No. Neither MGF nor PEG-MGF is approved by the FDA or any other regulator for any use. Material sold under these names is intended for laboratory research only, and nothing here should be read as endorsing human use.
Is PEG-MGF banned in sports?
Yes. Both MGF and PEG-MGF are prohibited by the World Anti-Doping Agency under Section S2 (peptide hormones, growth factors, related substances and mimetics), in and out of competition. Athletes subject to testing should treat them as banned.
What doses are commonly reported?
Community reports most often describe 200–400 mcg per injection, with the wider range spanning roughly 100–600 mcg, over 4–8 week periods. These are reported examples for education only, not a recommendation or a safe personal dose.
Why is MGF often paired with IGF-1 LR3?
A common model holds that MGF expands the satellite (stem) cell pool while IGF-1 drives those cells to differentiate. Reported protocols therefore separate the two by several hours rather than injecting them together, since simultaneous exposure is thought to reduce the effect. This is reported practice, not medical advice.
Compliance and trust notes
Educational content only; no personalized health or outcome claims.
No personalized use recommendation outputs.
Use this material for general learning and research-context literacy.
Educational use only — not medical advice. This guide summarizes information reported in published research and community practice for educational purposes. It is not medical advice and not a recommendation to use any compound. Any doses, schedules, or combinations shown are examples of what has been reported, not instructions for you. Many peptides described here are research compounds that are not FDA-approved for the uses discussed and may be investigational or restricted. Effects, risks, and legal status vary; individual needs and results vary. Consult a qualified, licensed healthcare professional before making any decision. Do not use this content to diagnose, treat, or dose yourself.
