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YK-11 Myostatin Inhibitor, 5 mg

4.71 out of 5
(201 customer reviews)


SKU: YK11-5MG Category: Tags: , , , ,


YK-11 (Myostatin Inhibitor) Research Profile:

dependent on stack
dependent on stack
dependent on stack
dependent on stack

Description: Myostatin inhibitor -- reduces the body's natural limitations on muscle-growth imposed by naturally-occurring myostatin protein in mammals; often ran concurrently with any SARM or Prohormone.

Known for: Muscle mass increases by inhibiting myostatin.

Commonly stacked with: Typical bulking stack: YK-11, MK-677 and RAD-140/or/LGD-4/or/S-4/or/S-23 | optional: MK-2866

Side-effects: Very few reports of adverse side-effects


YK-11 (Myostatin Inhibitor) Chemical Profile:

Clinical data

Selective Androgen Receptor Modulator, Myostatin Inhibitor
YK-11, YK11, (17ฮฑ,20E)-17,20-[(1-methoxyethylidene)bis(oxy)]-3-oxo-19-norpregna-4,20-diene-21-carboxylic acid methyl ester
By mouth
US: Investigational New Drug
Excenen Pharmatech, ChemIDplus

Pharmacokinetic data

6-10 hours


Methyl (2E)-2-[(8R,9S,10R,13S,14S,17S)-2'-methoxy-2', 13-dimethyl-3-oxospiro[1,2,6,7,8,9,10,11,12,14,15, 16-dodecahydrocyclopenta[a]phenanthrene -17,5'-1,3-dioxolane]-4'-ylidene]acetate

Chemical and physical data

430.54 g/mol
C[C@]12CC[C@H]3[C@H]([C@@H]1CC[C@@]24/C(=C\ C(=O)OC)/OC(O4)(C)OC)CCC5=CC(=O)CC[C@H]35
1S/C25H34O6/c1-23-11-9-18-17-8-6-16(26) 13-15(17)5-7-19(18)20(23)10-12-25(23)21(14-22(27) 28-3)30-24(2,29-4)31-25/h13-14,17-20H,5-12H2,1- 4H3/b21-14+/t17-,18+,19+,20-,23-,24?,25+/m0/s1


* These statements have not been evaluated by the Food and Drug Administration. These products are not intended to diagnose, treat, cure, or prevent any disease. Selective Androgen Receptor Modulators (SARMs) have not been approved in the US by the FDA for human consumption as dietary supplements. In accordance with US laws pertaining to the use of Investigational New Drugs (IND's) products labeled as SARMs on this website are sold for laboratory and clinical research purposes only, are intended solely for investigational use, and are to be used exclusively for purposes of a clinical trial that is the subject of an effective investigational new drug application; otherwise, you are not authorized to purchase our products. By using this site and/or purchasing our products, you certify you and/or your organization is/are qualified to possess, handle, and administer the products you purchase, that SARMTECH and its owners/agents are not liable for any unintended effects or outcomes, and that you are 21 years of age or older.


201 reviews for YK-11 Myostatin Inhibitor, 5 mg

  1. 5 out of 5

    Kolbie G. (verified owner)

    Best muscle builder research subject has taken

  2. 4 out of 5

    Kristopher Morrow (verified owner)

    It really does work

  3. 5 out of 5

    David P. (verified owner)


  4. 5 out of 5

    Walid Z. (verified owner)


  5. 3 out of 5

    Adrian (verified owner)

    It was okei! But no sick gains! Subject gained about 4kg

  6. 3 out of 5

    scott (verified owner)


  7. 5 out of 5

    Emanuel Stamathis (verified owner)

    This stuff is for real!! Sorry to see these orals go!

  8. 5 out of 5

    Anonymous (verified owner)

    Definite increases in muscle mass, great product.

  9. 5 out of 5

    Anonymous (verified owner)


  10. 5 out of 5

    Allen (verified owner)

    Seems to be an excellent addition to stack with LGD, enhancing the strength gains. This is the subjectss 1st stack with YK11, after using LGD alone for several rounds. Will try to add in on other cycles.

  11. 5 out of 5

    David P. (verified owner)


  12. 5 out of 5

    Anonymous (verified owner)


  13. 5 out of 5

    Kevin S. (verified owner)

    Researched for 8 weeks in a super stack. All I can say is wow to test results!

  14. 4 out of 5

    Edward H. (verified owner)


  15. 5 out of 5

    Robert Alley (verified owner)

    The yk11 has been a great addition to my sarm stack. Subject is 52 years old feeling great. His testosterone levels are high and has gained 12 pounds of muscle in a month, sometimes works out twice a day. Subject eating like a beast and feels like a bull.

  16. 5 out of 5

    alan cucchiella (verified owner)

    Works great nice dosage great price

  17. 5 out of 5

    Jamie W. (verified owner)

    Subject feels great. Will order it again.

  18. 5 out of 5

    Aadel Benchaita (verified owner)


  19. 5 out of 5

    Jessie S. (verified owner)


  20. 5 out of 5

    JEFFREY (verified owner)

    This yk-11 is the best I have seen to date. Works extremely well and the price cannot be beat.

  21. 5 out of 5

    Benjamin R. (verified owner)

    Purchased with FreeUp testosterone booster. Subject experienced bigger gains in muscle with this than was getting with LGD. Researched with both of those sarms separate and saw very good results. Researched them on second cycle stacked together and subject gained same amount of muscle in one week than did in 4. Wow!

  22. 5 out of 5

    Miguel B. (verified owner)


  23. 5 out of 5

    David P. (verified owner)

    Subject’s workouts are much more explosive, with big gains. I recommend these sarms.

  24. 5 out of 5

    Anonymous (verified owner)

    great gains

  25. 5 out of 5

    Demetrius Alexander (verified owner)


  26. 5 out of 5

    Benjamin C. (verified owner)

    Product works great. Subject gained some solid size!

  27. 5 out of 5

    JEFFREY (verified owner)

    Best YK-11 I’ve seen yet. This stuff adds mass quick.

  28. 5 out of 5

    Justin Cabrera (verified owner)


  29. 5 out of 5

    Zachary (verified owner)

    Great product, starts working great within just the first couple weeks!

  30. 3 out of 5

    Melissa (verified owner)


  31. 5 out of 5

    Matthew Morgan (verified owner)

    Excellent service & delivery great company to purchase from

  32. 5 out of 5

    Benjamin C. (verified owner)

    It worked extremely well was happy with my results.

  33. 5 out of 5

    Fabiano Purper (verified owner)


  34. 5 out of 5

    Fabian (verified owner)

    Great product! Subject has been feeling good. More reps less burning in muscles. I could see results in subject after 1 week 1/2 of use (with proper diet)
    Side effects encountered :
    – A little bit of joint pain but nothing alarming
    – hair grows faster
    – aggressivity & more sensitive the first 2 weeks of use
    – More hungry
    Next purchase will be yk stack with Lgd.
    Love it so far!

  35. 5 out of 5

    Kieran F. (verified owner)

    Subject bigger than has ever been, this stuff works

  36. 4 out of 5

    Anonymous (verified owner)


  37. 5 out of 5

    Timothy (verified owner)

    Subject used with pre-workout. Worked really well. Very happy will buy again. Thank You!

  38. 5 out of 5

    Shari M. (verified owner)


  39. 5 out of 5

    Anonymous (verified owner)


  40. 5 out of 5

    Joseph (verified owner)

    Really helps with showing more striations from the muscle.

  41. 5 out of 5

    Janne M. (verified owner)


  42. 4 out of 5

    jeremy piras (verified owner)


  43. 5 out of 5

    David (verified owner)

    Very happy with this product

  44. 3 out of 5

    CHRISTOPHER P SIMARD (verified owner)


  45. 5 out of 5

    Mike C. (verified owner)

    Subject normally hits a certain size and stops. In the month I’ve been on this study, subject gained half an inch in arms and chest is looking Great! Will be using these products more.

  46. 5 out of 5

    Mjjc5291 (verified owner)

    Test subjects noticed increase in muscle fullness/hardness, decrease in body fat, increase in appetite, some subject had mild hair loss, increase in strength, and an apparent decrease in natural test. Highly recommend pct for test subjects but all mild side effects were reversible during pct. a size and bulk research chemical that is top notch from sarmtech.nl thank you for existing guys!!!

  47. 4 out of 5

    Samuel R (verified owner)

    I only noticed a small effect. I think my research subject was supposed to take this with another sarm tho?

  48. 4 out of 5

    brooklynbeast (verified owner)

    Great product except i ordered YK11 but got RAD140! The rad experiment is very strong though and I got the better deal

    UPDATE: I emailed James at Sarmtech and they immediately sent me a bottle of YK… 2nd day air! I can’t update the stars but if i could i’d give you guys 6!!

  49. 4 out of 5

    Tim Leigh (verified owner)

    Very strong, definitely seeing growth results. I also take a multivit, omega, vit e,a,k, omega, turmeric, glucosamine. Any advice apprecieated.

  50. 5 out of 5

    casey (verified owner)

    Overall very impressed with sarmtech products. This YK-11 was very potent – much more so than my first purchase which was blackstone , found on ebay … not even sure if there product did anything. Capsule qty is 90 vs 60, which is also great. This was shipped out same day and arrived in 2 days too.

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