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Human Growth Hormone (HGH) vs IGF-1 LR3 vs MGF (Mechano Growth Factor)

A three-way comparison to help you find the right peptide for your research goals.

Human Growth Hormone (HGH)

Human Growth Hormone (somatropin) is a 191-amino acid protein identical to naturally produced GH. FDA-approved for growth hormone deficiency, Turner syndrome, and other conditions. Widely used off-label for anti-aging and performance.

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IGF-1 LR3

IGF-1 LR3 (Long R3 Insulin-like Growth Factor-1) is a modified version of IGF-1 with extended half-life and enhanced potency. The modifications prevent binding to IGF binding proteins, increasing bioavailability.

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MGF (Mechano Growth Factor)

MGF (Mechano Growth Factor) is a splice variant of IGF-1 that is produced locally in muscle tissue in response to mechanical stress. The non-PEGylated form has a very short half-life.

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Side-by-Side Comparison

AspectHuman Growth Hormone (HGH)IGF-1 LR3MGF (Mechano Growth Factor)
MechanismBinds to GH receptors throughout the body, stimulating IGF-1 production in the liver. Promotes protein synthesis, fat metabolism, and cellular regeneration across multiple tissues.Binds to IGF-1 receptors to promote protein synthesis, muscle growth, and fat metabolism. The LR3 modification (13 amino acid extension and arginine substitution) extends half-life from minutes to 20-30 hours.Activates muscle satellite cells (stem cells) and promotes their proliferation without differentiation, priming them for fusion with existing muscle fibers during repair and growth.
Typical DosageMedical: 0.1-0.3mg/kg/week divided into daily doses. Anti-aging: 1-2 IU daily. Performance: 2-6 IU daily, sometimes higher.Research protocols typically use 20-100mcg daily, often divided into multiple injections or administered bilaterally to target muscles.Due to extremely short half-life (minutes), typical protocols use 100-200mcg injected directly into target muscles immediately post-workout.
AdministrationSubcutaneous injection, preferably at night to mimic natural pulsatile release. Rotate injection sites. Store refrigerated.Intramuscular injection (site-specific growth) or subcutaneous for systemic effects. Often cycled 4-6 weeks on, equal time off.Intramuscular injection into trained muscles within minutes of workout completion. Must be used immediately after reconstitution due to instability.
Side EffectsJoint pain, water retention, carpal tunnel syndrome, potential insulin resistance, and acromegaly features with long-term high doses.Hypoglycemia, joint pain, water retention, potential jaw/hand growth with extended use, and injection site reactions.Injection site soreness, potential hypoglycemia, localized swelling. Short half-life limits systemic effects.
Best For

What They Have in Common

Human Growth Hormone (HGH), IGF-1 LR3, MGF (Mechano Growth Factor) are all commonly used for:

Key Differences

Unique to Human Growth Hormone (HGH):

Unique to IGF-1 LR3:

Detailed Analysis

Commonalities

Both Human Growth Hormone (HGH) and IGF-1 LR3 are commonly used for Muscle Growth, Fat Loss, Recovery & Healing.

Which Should You Choose?

Human Growth Hormone (HGH) has stronger evidence for Fat Loss, Recovery & Healing.

Commonalities

Both Human Growth Hormone (HGH) and MGF (Mechano Growth Factor) are commonly used for Muscle Growth, Recovery & Healing.

Which Should You Choose?

Human Growth Hormone (HGH) has stronger evidence for Muscle Growth, Recovery & Healing.

Commonalities

Both IGF-1 LR3 and MGF (Mechano Growth Factor) are commonly used for Muscle Growth, Recovery & Healing.

Which Should You Choose?

IGF-1 LR3 has stronger evidence for Muscle Growth.

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