Head to head
IGF-1 LR3 against MGF
Two products sold from the same hormone family for different jobs, systemic growth against local repair. Both have animal and cell evidence only, and MGF's half-life is measured in minutes, which is difficult to reconcile with how it is dosed.
Column A
IGF-1 LR3Long R3 Insulin-like Growth Factor 1
A long-acting analogue of IGF-1 studied in animal models for muscle growth and tissue repair.
Column B
MGFMechano Growth Factor (IGF-1Ec E-peptide)
A 24 amino acid fragment of a load-induced IGF-1 splice variant, sold for local muscle repair. The published record is cell and animal work, including at least one failed replication, with no human study of any design and a half-life of minutes.
Side by side, on the facts we can check
| Attribute | IGF-1 LR3 | MGF |
|---|---|---|
| Category | Growth Hormone | Muscle & Performance |
| FDA status | Not FDA-approved | Not approved |
| Half-life | ~20-30 hours | Minutes (native peptide) |
| Molecular weight | 9,111 Da | Not verified (24 amino acid E-domain peptide) |
| Mechanism | Activates the IGF-1 receptor, driving cellular growth, proliferation, and protein synthesis; reduced binding-protein affinity prolongs activity. | Proposed activation of muscle satellite cell proliferation through a receptor distinct from IGF-1R. |
| Human studies cited | 0 | 0 |
| Legal status, US | Not approved; research use only | Not approved; sold 'for research use only' |
Frequently asked questions
What is the difference between IGF-1 LR3 and MGF?
IGF-1 LR3: A long-acting analogue of IGF-1 studied in animal models for muscle growth and tissue repair. MGF: A 24 amino acid fragment of a load-induced IGF-1 splice variant, sold for local muscle repair. The published record is cell and animal work, including at least one failed replication, with no human study of any design and a half-life of minutes.
Which has stronger research evidence, IGF-1 LR3 or MGF?
This database does not grade compounds. It counts what was run in people: 0 of the 3 studies cited on the IGF-1 LR3 profile were human work, against 0 of 3 for MGF. Those counts are of our own citation lists and understate any larger literature, and neither is a recommendation.
Are IGF-1 LR3 and MGF FDA-approved?
IGF-1 LR3: Not FDA-approved. MGF: Not approved.
Reviewed Sep 2026. This page sets two published records side by side. It is educational, it is not medical advice, and it contains no dosing protocols or recommendations for personal use.