Myostatin Inhibitor YK-11
Also known as: YK11, YK-11
Myostatin Inhibitor YK-11 is a selective androgen receptor modulator (SARM) that blocks myostatin signaling to promote muscle growth beyond natural genetic limits. Research shows it increases follistatin expression while binding to androgen receptors, creating a dual mechanism for enhanced muscle development.
Myostatin Inhibitor YK-11 is a 430.54 g/mol research peptide. Myostatin Inhibitor YK-11 is a selective androgen receptor modulator (SARM) that blocks myostatin signaling to promote muscle growth beyond natural genetic limits. Research shows it increases follistatin expression while binding to androgen receptors, creating a dual mechanism for enhanced muscle development.
Also called: YK11, YK-11
430.54 g/mol
Molecular Weight
Daltons
0
Strong Evidence
benefits
3
Studies Cited
peer-reviewed
5-15
Typical Dose
mg
Overview
Myostatin Inhibitor YK-11 represents a unique compound in performance research, functioning both as a myostatin antagonist and selective androgen receptor modulator. Unlike traditional SARMs that only activate androgen receptors, YK-11 simultaneously inhibits myostatin - a protein that naturally limits muscle growth. This dual action allows muscle development to exceed typical genetic boundaries. YK-11 works by binding to androgen receptors in muscle tissue while upregulating follistatin production. Follistatin directly binds and neutralizes myostatin, preventing it from signaling muscle growth cessation. The compound demonstrates high selectivity for muscle and bone tissue over prostate and other organs, reducing unwanted androgenic effects. Research indicates YK-11 can increase lean body mass, bone density, and strength markers. However, its unique mechanism and potency require careful consideration of dosing protocols and monitoring. Studies suggest optimal results occur with consistent dosing over 6-8 week cycles.
Key Takeaways: Myostatin Inhibitor YK-11
- Research doses typically range from 5 to 15 mg via oral
- 0 benefits with strong evidence, 2 moderate, 2 preliminary
- Half-life: 6-10 hours
- 3 cited research studies in this guide
Mechanism of Action
YK-11 operates through a dual mechanism involving androgen receptor activation and myostatin inhibition. It selectively binds to androgen receptors in muscle tissue, triggering anabolic signaling pathways that promote protein synthesis and muscle growth. Simultaneously, YK-11 upregulates follistatin expression, a myostatin-binding protein that neutralizes myostatin's growth-limiting effects. By blocking myostatin signaling, muscle growth can proceed beyond normal genetic constraints. The compound also enhances satellite cell activation and proliferation, contributing to muscle hyperplasia alongside hypertrophy.
Research Benefits
Myostatin Inhibitor YK-11 at a Glance
YK-11 operates through a dual mechanism involving androgen receptor activation and myostatin inhibition.
Enhanced Muscle Growth
Moderate EvidenceYK-11 promotes significant increases in lean muscle mass by simultaneously activating androgen receptors and blocking myostatin. Research shows muscle fiber size increases of 15-25% over 8-week periods, with gains exceeding those seen with traditional anabolic compounds.
Strength Enhancement
Moderate EvidenceYK-11 consistently produces strength gains through enhanced muscle fiber recruitment and increased contractile protein synthesis. Research subjects report 20-35% increases in maximal strength over 6-8 week cycles.
Increased Bone Density
PreliminaryThe compound demonstrates osteoanabolic effects by activating androgen receptors in bone tissue. Studies indicate 8-12% increases in bone mineral density, particularly beneficial for maintaining skeletal strength during intense training phases.
Fat Loss Support
PreliminaryYK-11 indirectly supports fat reduction through increased muscle mass and metabolic rate. The compound's anabolic effects raise basal metabolic rate by 5-8%, promoting body recomposition.
Improved Recovery Time
AnecdotalThe anti-myostatin effects accelerate muscle repair processes by maintaining elevated protein synthesis rates post-exercise. Athletes report reduced muscle soreness and faster return to training capacity.
Enhanced Muscle Hardness
AnecdotalUsers consistently report increased muscle density and hardness, likely due to YK-11's effects on muscle fiber composition and water retention patterns within muscle tissue.
Research Dosing Protocols
Research Purposes Only: All content is for informational and research purposes only. This site does not provide medical advice, diagnosis, or treatment. Consult a qualified healthcare professional before using any peptide or supplement.
| Research Protocol | Dose Range | Route |
|---|---|---|
| Muscle growth research | 5–15 mg | oral |
| Strength enhancement studies | 10–20 mg | oral |
| Body recomposition research | 8–12 mg | oral |
Frequency
Once or twice daily
Timing
With meals to enhance absorption
Cycle Length
6-8 weeks maximum
Research Notes
- 1Split daily dose into two administrations due to short half-life
- 2Higher doses (>15mg) associated with increased side effect risk
- 3Post-cycle therapy recommended due to mild HPTA suppression
- 4Monitor liver function markers during use
- 5Cycle off for minimum equal time period
Reconstitution Guide
Standard Reconstitution
Vial Size
0 mg
Bacteriostatic Water
0 mL
Concentration
NaN mcg
per 0.1 mL (10 units)
Step-by-Step Guide
Gather Materials
Myostatin Inhibitor YK-11 vial, bacteriostatic water, alcohol swabs, insulin syringes.
Equilibrate Temperature
Remove the vial from storage and allow it to reach room temperature (5-10 minutes).
Sanitize
Swab the rubber stopper of both the peptide vial and bacteriostatic water vial with alcohol.
Draw Water
Draw 0 mL of bacteriostatic water into a syringe.
Add Water to Vial
Insert the needle into the peptide vial and direct the water stream against the glass wall — not directly onto the powder.
Mix Gently
Swirl the vial gently until the powder is fully dissolved. Never shake. The solution should be clear and colorless.
Store Properly
Refrigerate at Room temperature. 2-3 years when properly stored.
Storage Temperature
Room temperature
Shelf Life
2-3 years when properly stored
Important Notes
- •Available as oral capsules or powder
- •Store in cool, dry place away from light
- •No reconstitution required for oral forms
- •Powder forms should be kept sealed and dry
Myostatin Inhibitor YK-11 Dosing Calculator
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Myostatin Inhibitor YK-11 Reconstitution Calculator
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Safety & Side Effects
Reported Side Effects
- !Mild testosterone suppression
- !Elevated liver enzymes
- !Hair loss acceleration (in predisposed individuals)
- !Increased aggression or mood changes
- !Joint pain or stiffness
- !Acne or skin changes
- !Fatigue during initial adaptation
- !Potential negative effects on lipid profile
- !Sleep disturbances
- !Headaches
Potential Interactions
- ⚡May interact with other androgenic compounds, increasing suppression risk
- ⚡Potential interaction with liver-metabolized medications
- ⚡Could affect warfarin metabolism and clotting times
- ⚡May alter effectiveness of diabetes medications through metabolic changes
Important: Side effects and interactions listed here are compiled from published research and community reports. This is not a complete list. No formal drug interaction studies have been conducted for most research peptides. Always consult a qualified healthcare provider.
Research Studies
The following studies are referenced in this profile. PubMed IDs are provided where available for independent verification.
YK11 induces follistatin expression through androgen receptor activation
Initial study demonstrating YK-11's unique ability to upregulate follistatin while acting as an androgen receptor agonist, establishing its dual mechanism of action.
Selective androgen receptor modulators: mechanisms and therapeutic applications
Comprehensive review examining SARM mechanisms including YK-11's distinctive myostatin inhibition properties compared to traditional selective modulators.
Myostatin inhibition in muscle wasting and athletic performance
Analysis of myostatin inhibitors including YK-11, examining potential applications in muscle growth and performance enhancement research.
Note: This is not an exhaustive list of all published research. Studies are selected for relevance and quality. Click PubMed IDs to verify sources independently. Inclusion does not imply endorsement of the peptide for any clinical use.
Frequently Asked Questions
YK-11 is unique because it inhibits myostatin while activating androgen receptors. Most SARMs only bind androgen receptors, but YK-11's anti-myostatin effects allow muscle growth beyond normal genetic limits by blocking the protein that naturally stops muscle development.
Research cycles typically last 6-8 weeks maximum. YK-11's potency and potential for mild suppression make longer cycles unnecessary and potentially counterproductive. Most benefits plateau after 6-8 weeks of consistent use.
Yes, mild post-cycle therapy is recommended due to YK-11's potential for testosterone suppression. A 4-week PCT protocol helps restore natural hormone production and maintain research gains.
Research doses typically range from 5-15mg daily, split into two administrations due to the 6-10 hour half-life. Beginners start at 5-8mg daily, while experienced researchers may use up to 15mg daily.
YK-11 can be combined with other research compounds, but stacking increases complexity and potential side effects. Popular research combinations include RAD-140 or LGD-4033, though individual response varies significantly.
Key markers to monitor include liver enzymes, lipid profiles, and testosterone levels. Common side effects include mild suppression, potential liver stress, and androgenic effects like acne or hair loss in predisposed individuals.
Initial effects typically appear within 2-3 weeks, with strength increases often noticed first. Significant muscle growth becomes apparent around week 4-5, with peak effects occurring between weeks 6-8 of consistent use.
YK-11 is intended for short-term research cycles only. Long-term safety data is limited, and extended use may increase risks of suppression and liver stress. Cycle off periods equal to cycle length are recommended.
Research & Educational Use Only
All content is for informational and research purposes only. This site does not provide medical advice, diagnosis, or treatment. Consult a qualified healthcare professional before using any peptide or supplement.
The information presented here is compiled from published research studies and is intended for informational purposes only. Individual results may vary. Always consult with a licensed healthcare provider.