YK-11 is often classified as a Selective Androgen Receptor Modulator (SARM), but it functions quite differently from typical SARMs. This unique compound has gained significant attention in bodybuilding communities for its potential to simultaneously promote muscle growth and decrease fat tissue. Research suggests that YK-11 works by binding to androgen receptors and potentially increasing follistatin levels, which may inhibit myostatin—a protein that limits muscle growth.
Unlike traditional SARMs, YK-11 appears to have properties of both a SARM and a myostatin inhibitor. This dual mechanism makes it particularly interesting to researchers studying performance enhancement. Whilst some bodybuilders report impressive strength and size gains, it’s crucial to understand that YK-11 remains largely unresearched in human subjects.
The scientific community has expressed concerns about YK-11’s safety profile due to limited clinical testing. Most available information comes from preliminary cell studies rather than comprehensive human trials. Bodybuilders considering this compound should be aware that its legal status varies by country, and potential side effects are not fully documented.
Understanding YK-11 and Its Mechanism of Action
YK-11 is a unique compound that functions both as a Selective Androgen Receptor Modulator (SARM) and a myostatin inhibitor. Its dual mechanism provides distinctive effects on muscle growth through specific biochemical pathways and receptor interactions.
The Chemistry Behind YK-11
YK-11, chemically known as (17α,20E)-17,20-[(1-methoxyethylidene)bis(oxy)]-3-oxo-19-norpregna-4,20-diene-21-carboxylic acid methyl ester, has a steroidal structure unlike most SARMs. It was first synthesised by Japanese researcher Yuichiro Kanno in 2011.
The compound acts as a partial agonist to androgen receptors, meaning it selectively binds to these receptors in muscle and bone tissue whilst having limited activity in other tissues. This selectivity is what classifies it as a SARM.
YK-11’s unique molecular structure allows it to interact with androgen receptors differently than traditional anabolic steroids. It doesn’t fully activate these receptors but instead triggers specific anabolic pathways.
The compound has shown activity in C2C12 myoblasts, which are precursor cells that develop into muscle fibres, promoting myogenic differentiation through multiple pathways.
YK-11 as a Myostatin Inhibitor
Myostatin is a protein that naturally limits muscle growth in the body. YK-11’s most remarkable feature is its ability to function as a myostatin inhibitor.
Research suggests YK-11 increases follistatin expression in muscle cells. Follistatin is a protein that binds to and inhibits myostatin, effectively removing the “brakes” on muscle growth.
This dual mechanism—androgenic activity plus myostatin inhibition—potentially makes YK-11 more effective for muscle growth than other SARMs that work through androgen receptors alone.
In laboratory studies on muscle cells, YK-11 has demonstrated significant anabolic activity at even lower concentrations than many traditional SARMs or steroids.
The compound appears to influence key genetic pathways involved in protein synthesis and muscle cell differentiation, leading to enhanced muscle development.
Comparison with Other SARMs
Unlike popular SARMs such as LGD-4033 (Ligandrol), YK-11 has a steroidal chemical structure whilst maintaining selective activity. This gives it a unique profile among SARMs.
| SARM | Primary Mechanism | Structure | Potency |
|---|---|---|---|
| YK-11 | Dual (AR activation + myostatin inhibition) | Steroidal | High |
| LGD-4033 | AR activation only | Non-steroidal | Moderate |
| Cardarine GW-501516 | PPAR-delta activation (not actually a SARM) | Non-steroidal | Varies |
| Stenabolic | REV-ERBα agonist (not actually a SARM) | Non-steroidal | Moderate |
Compared to traditional anabolic steroids, YK-11 may offer more selective action with potentially fewer side effects, though clinical human studies remain limited.
The active pharmaceutical ingredient (API) of YK-11 shows different binding characteristics than most SARMs, which may explain its distinctive effects on muscle tissue.
Clinical Applications and Benefits of YK-11
YK-11 represents a novel class of Selective Androgen Receptor Modulators (SARMs) with unique mechanisms that differentiate it from traditional options. Research suggests it may offer significant advantages for muscle development and skeletal health through its distinctive biochemical interactions.
Influence on Muscle Mass and Strength
YK-11 demonstrates remarkable potential for enhancing muscle mass through multiple pathways. Studies indicate it functions as a myostatin inhibitor, effectively removing a natural limiter to muscle growth. This mechanism allows for potentially greater muscle development compared to standard SARMs.
Research shows YK-11 promotes protein synthesis by activating follistatin production. This biological process is crucial for the development of lean muscle tissue and improved recovery between training sessions.
In laboratory investigations, YK-11 has shown anabolic effects comparable to testosterone at significantly lower dosages. Its selective action potentially offers targeted muscle enhancement with fewer systemic effects.
Athletes utilising YK-11 commonly report:
- Increased strength within 2-4 weeks
- Enhanced muscle hardness and definition
- Improved performance during resistance training
Potential for Bone Density Improvements
YK-11 shows promising effects on bone mineral density through its action on androgen receptors in bone tissue. Preliminary research suggests it may stimulate osteoblast activity, the cells responsible for bone formation.
In vitro studies demonstrate YK-11’s ability to increase bone-forming proteins and minerals. These findings indicate potential applications for conditions like osteoporosis and age-related bone density loss.
The bone-strengthening effects appear to work synergistically with the compound’s muscle-building properties. This dual-action provides comprehensive musculoskeletal benefits that support both function and structure.
Unlike some anabolic compounds that may actually decrease bone quality over time, YK-11’s selective activity appears to support bone health without detrimental effects to bone architecture.
YK-11 Dosing, Administration, and Safety
YK-11 requires careful consideration regarding dosage, safety protocols, and proper handling for research purposes. This selective androgen receptor modulator (SARM) has specific administration guidelines and potential side effects that must be understood before use.
Recommended Dosage and Cycle Information
For research purposes, YK-11 is typically studied at concentrations between 5-15mg daily. Most research protocols utilise 10mg as an optimal dosage, often divided into two 5mg administrations to maintain stable compound levels.
Research cycles commonly last 4-8 weeks, with 6 weeks being the standard duration due to the potent nature of YK-11. Longer research periods have not demonstrated proportionally increased benefits and may elevate risk profiles.
Sample Research Protocol:
- Week 1-2: 5mg daily (divided doses)
- Week 3-6: 10mg daily (divided doses)
- Post-cycle: Comprehensive post-cycle therapy
YK-11’s potential to influence testosterone production means appropriate post-cycle protocols are essential to help restore natural hormone production.
Safety Profile and Side Effects
YK-11 presents several potential concerns in research settings that warrant careful monitoring:
Common Observed Effects:
- Testosterone suppression
- Elevated liver enzymes
- Hair thinning (androgenic response)
- Blood pressure changes
Unlike some milder SARMs, YK-11 demonstrates more pronounced androgenic properties, potentially causing hormone-related side effects. Its steroidal structure differs from other SARMs and may contribute to its unique safety profile.
Research data suggests YK-11 may impact cholesterol levels, with decreased HDL (good cholesterol) being reported in some studies. Regular blood work is considered essential when researching this compound.
Limited clinical data exists regarding YK-11’s long-term effects, making extended research protocols inadvisable until more comprehensive safety information becomes available.
Solubility and Preparation for Research
YK-11 presents specific challenges regarding solubility that researchers must address for accurate administration. The compound demonstrates poor water solubility, necessitating appropriate solvents for research applications.
Solubility Properties:
- DMSO: Primary solvent of choice (99.9% purity recommended)
- Ethanol: Alternative solvent option
- PEG-400: Sometimes used in specific research protocols
To prepare YK-11 solutions, researchers typically dissolve the compound at concentrations of 10-20mg/ml. Gentle heating (not exceeding 30°C) and sonication may facilitate dissolution. Solutions should be stored in amber glass containers away from light and heat.
The stability of prepared solutions is approximately 2-3 weeks when refrigerated. Researchers should verify the purity of raw YK-11 material (minimum 98% purity) before preparation to ensure research validity.
Where to buy YK11 SARM in United Kingdom
Finding a reliable source for YK11 SARM in the UK requires careful research. Consumers should prioritise vendors that offer laboratory-tested products with verified purity.
Steroids-uk.com Shop stands out as a the most reputable SARMS supplier in the UK market. They provide laboratory-tested SARMS for sale with documentation verifying compound purity and quality.
The online store offers highest-purity YK11 SARM available to UK customers, with concentrations typically reaching 99% purity according to their published lab results. Each batch undergoes independent testing to ensure consistency.
Next-day delivery options are available for most UK addresses when orders are placed before 2pm. This service proves particularly valuable for researchers requiring prompt product arrival.
Customer Verification:
- Over 3,000 online store reviews with an average rating of 4.8/5
- Third-party verification through Reviews.io platform
- Established presence in the UK market for more than 5 years
The company provides comprehensive product information, including dosage recommendations and potential effects based on available research literature.
Frequently Asked Questions
What are the potential side effects associated with the use of YK-11?
YK-11 may cause several side effects that users should be aware of. Testosterone suppression is commonly reported, often leading to decreased natural hormone production.
Hair loss has been observed in some users, particularly those with genetic predispositions to male pattern baldness.
Liver toxicity is another concern, as YK-11 may elevate liver enzymes. Regular blood work is advisable during usage periods.
Joint pain sometimes occurs due to rapid muscle growth outpacing tendon and ligament development. This can increase injury risk during training.
How does YK-11 influence myostatin levels in the body?
YK-11 functions as a myostatin inhibitor, directly reducing the body’s myostatin production. Myostatin naturally limits muscle growth, so lower levels allow for enhanced muscle development.
Research suggests YK-11 increases follistatin expression, a protein that binds to and inhibits myostatin. This dual action creates a powerful environment for muscle growth.
The compound appears to work through androgen receptor activation while simultaneously affecting myostatin pathways, making it unique among SARMs.
In what ways do YK-11 and RAD140 differ in their effects on muscle growth and performance enhancement?
YK-11 acts as both a SARM and a myostatin inhibitor, potentially offering more dramatic muscle growth than RAD140. It may produce more rapid gains but carries higher risk profiles.
RAD140 (Testolone) functions primarily through androgen receptor activation, providing more gradual muscle development with typically fewer side effects. It often produces drier gains with less water retention.
The anabolic-to-androgenic ratio differs between the compounds, with RAD140 showing more selective tissue targeting compared to YK-11’s broader effects on multiple pathways.
Can YK-11 use potentially lead to carcinogenic outcomes?
Limited research exists on YK-11’s long-term carcinogenic potential, which presents a significant concern. The compound’s mechanism of altering cellular pathways could theoretically influence cell division processes.
Some preliminary studies suggest that DHT-derived compounds like YK-11 might affect prostate cells, though conclusive human evidence is lacking.
The lack of comprehensive clinical trials means cancer risks remain largely theoretical but cannot be dismissed, especially with extended usage periods.
What mechanisms contribute to the neuroprotective or neurotoxic effects of YK-11?
YK-11’s interaction with androgen receptors in neural tissue may offer some neuroprotective benefits similar to other androgens. These receptors are present throughout the central nervous system.
The compound potentially increases brain-derived neurotrophic factor (BDNF), supporting neural health and cognitive function. However, this effect requires further validation in human studies.
Conversely, disruption of normal hormonal balance could potentially harm neurological function, particularly with long-term use or excessive dosages. The compound’s impact on estrogen levels may also affect cognitive processes.
Under what aliases is YK-11 known in the pharmacological and bodybuilding communities?
YK-11 is sometimes referred to as “Myostine” due to its myostatin-inhibiting properties. This name highlights its primary mechanism of action.
In scientific literature, it appears under its chemical name “(17α,20E)-17,20-[(1-methoxyethylidene)bis(oxy)]-3-oxo-19-norpregna-4,20-diene-21-carboxylic acid methyl ester.”
Bodybuilding forums occasionally use nicknames like “The Hybrid” or “DHT SARM” to reference YK-11’s unique position as both a selective androgen receptor modulator and a DHT derivative.
