Myostine YK11-Xstream Force

  • Capsules 90x5mg
  • Batch and lot coded with publicly visible lab reports to ensure quality and transparency.
  • Free of adulterants, excipients and flow agents to ensure purity.
  • Over-weighed slightly to compensate for loss by adhesion.
  • PET single-wall blue bottle with UV resistance to minimize degradation.
  • Tamper-proof seal to ensure safety in transit.
  • Soft Gelatin Green Capsule
  • Compound mixed with Maltodextrin fine powder

100,00лв. (51.13 €)


Capsules 90x10mg

Type by



XSF Group



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XStreamForce SARMs – YK11 is quite possibly one of the most powerful SARMs on the market today, due to its unique nature as both a SARM and a myostatin inhibitor.

Not only is YK11 a SARM, which will help promote lean muscle growth, but it also inhibits myostatin, which unlocks your natural bodybuilding potential.

YK11 belongs to a class of research chemicals known as SARMS, which were initially developed to help treat muscle wasting in cancer patients. Selective androgen receptor modulators, or SARMs for short, have potent muscle building effects, and are generally well tolerated in studies. While they were initially created to help cancer patients combat muscle wasting, bodybuilders quickly caught on, and realized that healthy individuals who took SARMs could experience steroid-like effects. While there isn’t much clinical evidence regarding YK11, anecdotal evidence suggests it’s an incredibly potent muscle building agent. In fact, as we’ll explore soon, lab rats which were given YK11 as treatment experienced absolutely mind-boggling muscle growth and results.

These products are not for use in preventing, curing, or treating a particular disease or ailments. Sold for research purposes only. Not sold for human consumption.


While there are minimal YK11 studies regarding the effects on humans, we do know that this SARM has an extremely anabolic effect on animals. In fact, mice that have low levels of myostatin, which is what YK11 inhibits, have on average twice as much muscle mass as rats who don’t.

Here are some reported benefits of YK11 usage:

  • Rapid Muscle Growth
  • Increased Sex Drive
  • Enhanced Strength
  • Muscle Hardening

The biggest benefit of YK11 is the rapid muscle growth, as users often report gaining 10-15 pounds or more from one 12-week cycle of YK11.

Muscle Hardening

Another reason why people love YK11 is that it creates a muscle hardening effect that few other supplements on the market can manage.

In addition to the rapid muscle growth that will come from this compound, YK11 is also known for creating the “cut and dry” look that lifters love.

What’s more is that if you combine YK11 with SR9009 or GW1516 SARM meant for cutting, you could experience VERY fast and lean gains.

Increased Strength

Most people take this compound, because of its ability to rapidly increase strength in users. In fact, one study conducted at the Department of Internal Medicine at Yale University, found that treating mice with an anti-myostatin drug for just 4 weeks was associated with a huge increase in muscle strength.

Another study, published in the PNAS Journal, found that mice who lacked the myostatin inhibiting gene (which YK11 seems to turn off), literally had twice the physical strength as those mice who had the myostatin inhibiting gene.

Rapid Muscle Growth

While the long-term health effects of YK11 haven’t been studied in humans, there is evidence to suggest it’s an incredibly potent anabolic drug.

In fact, much of the anecdotal data and various logs of body builders and their experiences suggest that YK11 is comparable to a mild steroid cycle.

While the drug hasn’t been approved for human use by the FDA, you can be sure that body builders are using it to get jacked all over the world.

While more studies certainly need to be done on this compound, preliminary data and anecdotal evidence suggests that it’s an EXTREMELY potent muscle building compound, rivaling even the strongest of anabolic steroids.


Because there have been no human trials with YK11 treatment, there is no medically established dose of YK11 for human use to date. However, the general consensus amongst bodybuilders is that 10 mg is a good dosage for muscle growth and performance enhancement.

Here are the YK11 dosage guidelines:

  • Beginner Dose: 10 mg/day
  • Intermediate Dose: 15 mg/day
  • Advanced Dose: 20 mg/day

While some users have reported taking dosages as high as 30mg/day, most agree that taking between 10 mg and 15 mg to start is best.

A dose of 10mg per day of YK11 is recommended. Each bottle contains 90 doses of use. Cycle Length: 8 – 12 weeks.

Application Selective Androgen Receptor Modulator, Myostatin Inhibitor
CAS 1370003-76-1
Molar Mass 430.534 g/mol
Chemical Formula C25H34O6
IUPAC Name methyl 2- {5-methoxy-5,15′-dimethyl-5′-oxospiro [1,4-dioxolane-2,14′-tetracyclo

[², ⁷.0¹¹, ¹⁵] heptadecane]-6′-en-3-ylidene} acetate

Synonyms YK11, YK-11, Myostine
Storage Room temperature
Capsules 90x5mg
Organoleptic Profile Green Crystalline powder
Physical Form Soft Gelatin Transparent Capsule
Specification ≥98%
Terms This material is sold for laboratory research use only. Terms of sale apply.

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