Follistatin-344
Follistatin-344 (FST-344)
Releasing the brake on muscle growth
A naturally occurring protein that binds and neutralizes myostatin and activin — the body's built-in limiters on muscle growth. By sequestering myostatin, Follistatin-344 removes a key brake on hypertrophy, which is why it's one of the most discussed (and still early-stage) research peptides for muscle and recovery.
- Half-life
- ~30 hours
- Route
- Subcutaneous injection
- Typical dose
- Research-dependent
- Availability
- Research-only
Key Benefits
Neutralizes myostatin, a primary brake on muscle growth
May support lean-mass gains and hypertrophy
Reduces activin-mediated growth suppression
Researched for muscle-wasting conditions
Effect scales with your baseline myostatin genetics
Mechanism of Action
How Follistatin-344 works
Follistatin-344 works by neutralizing the growth-limiting TGF-beta ligands:
- Myostatin (MSTN) sequestration — binds circulating myostatin and blocks it from activating its receptor, lifting the primary genetic brake on muscle fiber growth.
- Activin inhibition — also binds activin, a related TGF-beta ligand, broadening its effect on the growth-suppression pathway.
- De-repressed satellite cells — with myostatin signaling reduced, satellite-cell activity and protein synthesis are less restrained, favoring hypertrophy.
- Local vs systemic — effect size depends heavily on baseline myostatin tone, which is strongly genetically determined — so responses vary widely between individuals.
Your Genetics & Follistatin-344
Genetic variants that affect your response
These SNPs determine how effectively Follistatin-344 works for you specifically. A genetic peptide report identifies your variants before you start.
The K153R variant alters myostatin activity. Your baseline myostatin tone sets how much brake there is to release — people with naturally higher myostatin signaling have more to gain from neutralizing it with Follistatin-344.
The R577X variant determines alpha-actinin-3 in fast-twitch fibers. Fiber-type genetics shape the hypertrophy ceiling and how much a myostatin-blocking peptide translates into visible muscle.
IGF-1 promoter variants set the anabolic signal that builds muscle once the myostatin brake is released. A stronger IGF-1 background amplifies the net effect of Follistatin-344.
The FokI variant influences muscle strength and mass response to training. It shapes the muscular background on which a myostatin-blocking peptide acts.
Which variants do you carry?
Upload your DNA data or order a kit to find out.
Evidence & Research
20+
Published studies
Animal studies and in vitro data with promising but limited clinical validation
Sourcing & access
Where to buy Follistatin-344
Follistatin-344 is sold as a research compound, not a licensed medicine, so quality and legal status vary widely by country and vendor. If you're sourcing it, treat independent purity testing as non-negotiable.
- Insist on a recent third-party Certificate of Analysis (COA) for the exact batch — labs like Janoshik verify purity and identity.
- Check the legal status where you live before ordering — it differs from country to country.
- Reconstitute correctly with bacteriostatic water and start at a conservative dose.
Swiss Chems is a US research-chemical supplier that publishes third-party Certificates of Analysis. Sold for research use only — check your local laws.
Before you buy: see whether your DNA actually responds to Follistatin-344, and at what dose. Analyze my DNA — $99 →
Educational information only, not medical advice. Some outbound links are affiliate links (disclosed, at no extra cost to you), and providers we partner with are listed first. Most peptides are not FDA-approved — consult a qualified professional and check your local laws before purchasing.
Common Stacks
Follistatin-344 is commonly combined with:
IGF-1
Muscle StackModerate EvidenceInsulin-like Growth Factor-1
The primary anabolic mediator of growth hormone. Most of GH's effects on muscle, tissue repair and growth are actually carried out by IGF-1, produced mainly in the liver. Native IGF-1 is short-acting and tightly regulated by binding proteins — making the IGF axis one of the most genetically variable in the body.
4
Gene variants
45+
Studies
CJC-1295
GH Axis StackModerate EvidenceCJC-1295 (Modified GRF 1-29)
A 29-amino-acid growth hormone releasing hormone (GHRH) analog with enhanced stability. CJC-1295 extends the duration of natural GH pulses without disrupting pulsatile release patterns, providing sustained elevation of growth hormone and IGF-1 for recovery, body composition, and anti-aging.
4
Gene variants
30+
Studies
ACE-031
Myostatin StackEmerging EvidenceACE-031 (Ramatercept)
A soluble decoy version of the activin receptor type IIB (ActRIIB). ACE-031 acts as a trap — it circulates and binds myostatin and related growth-limiting ligands before they can reach muscle, removing the brake on growth. It reached human trials for muscular dystrophy but was discontinued over vascular safety signals, so it remains research-only.
4
Gene variants
15+
Studies
Frequently Asked Questions
How does Follistatin-344 build muscle?
It doesn't build muscle directly — it removes a brake. Myostatin is a protein your body produces to limit muscle growth. Follistatin-344 binds and neutralizes myostatin (and activin), so the natural anabolic drive faces less resistance. How much that helps depends on how much myostatin you produce, which is genetic.
Why do results vary so much with Follistatin-344?
Because the effect depends on your baseline myostatin tone and muscle genetics. Someone with naturally high myostatin signaling has more brake to release; someone already low in myostatin (or carrying favorable muscle variants) may see less. MSTN and fiber-type genetics are the key predictors.
Does genetics affect Follistatin-344 response?
Yes. MSTN variants set how much myostatin brake there is to release, ACTN3 fiber-type genetics shape the hypertrophy ceiling, IGF1 sets the anabolic background, and VDR influences muscle response. A genetic peptide report profiles these for realistic expectations.
Learn More About Follistatin-344
Your next move
Two ways forward with Follistatin-344.
Not sure it's for you?
Will Follistatin-344 work for your genes — and at what dose?
Your report scores Follistatin-344 against your receptor, CYP and pathway variants — likely responder, non-responder, and a sensible starting dose — in minutes.
Analyze my DNA — $99Already decided?
Get Follistatin-344 from Swiss Chems.
A US research-chemical supplier with third-party Certificates of Analysis. Sold for research use only — check your local laws before ordering.
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