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YK-11 Myostatin Inhibitor, 5 mg

4.70 out of 5
(192 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 muscle-growth limitations imposed by naturally-occurring myostatin protein.

Known for: Inhibiting effects of 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, (17α,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.


192 reviews for YK-11 Myostatin Inhibitor, 5 mg

  1. 5 out of 5

    Lyon (verified owner)


  2. 5 out of 5

    Mike (verified owner)

    A real game changer. It’s hard to know when or how YK11 is working but after 6 weeks I can definitely see a difference.

  3. 5 out of 5

    Anonymous (verified owner)

    Love this product. Subject can really see the gains while using it.

  4. 5 out of 5

    Joshua (verified owner)

    first time stacking yk with my usual semiannual s4 and seemed like it boosted everything 20-30%, more strength, bigger lifts, gains came faster

  5. 4 out of 5

    Shawn Blackburn (verified owner)


  6. 5 out of 5

    Ariel (verified owner)

    I noticed huge gains

  7. 5 out of 5

    David (verified owner)

    My test subject performed very well. Would recommend this. Experienced no side effects.

  8. 5 out of 5

    Anthony (verified owner)


  9. 5 out of 5

    CHRIST KAZIAS (verified owner)

    This product is very interesting in that I saw results within a couple of weeks. No side effects at all. This is the real deal.

  10. 5 out of 5

    Dgoodsell (verified owner)

    Take this consistently even if you don’t see results early. The thing works

  11. 5 out of 5

    Aaron Abbott (verified owner)

    Strong as hell

  12. 5 out of 5

    Drew Hibbard (verified owner)

    Research went great. Fast shipping, and excellent customer service.

  13. 5 out of 5

    Ryan Layne (verified owner)

    Nice results

  14. 5 out of 5

    Chanse loudenback (verified owner)

    def worth the money

  15. 5 out of 5

    Mjjc5291 (verified owner)

    Love this! Huge increase in strength and staining with rage factor included hah! Very suppressive however very effective. Lean muscle mass gains with noticeable strength increase! Try this!

  16. 4 out of 5

    Ruben Abounaja (verified owner)

    Huge pumps from test subject

  17. 5 out of 5

    Larry Gabriel (verified owner)

    Good for building muscle and hair

  18. 5 out of 5

    Merman (verified owner)

    This is great stacked with YK11 and MK667

  19. 5 out of 5

    Tyler Dorsey (verified owner)

    Running this and LGD and I cant believe the fullness and size I have already [in research subject]. I’m going on 3rd week and [subject] gained 3lbs which is alot for him as he’s always been a lean person. Absolutely love this sarm!

  20. 5 out of 5

    Kirk Townsend (verified owner)

    YK-11 great sarm. Even better when stacked with lgd4033 & rad140.

  21. 3 out of 5

    William Morris (verified owner)

    Research subject ran SARMTECH YK at twice 5mg twice a day with 10mg LGD from another company. At first did not notice much. You have to give this a while. I started to notice a subtle difference in my body comp after three weeks. I have not notice much in terms of strength or size that I would attribute to this. Research subject’s body looks better and I think they are gaining a very slight amount of muscle and losing fat at the same time. It is not a big bulk builder and you have to take it consistently for a while. This is probably best to amplify effects of another SARM.

  22. 5 out of 5

    Ryan Maloy (verified owner)

    I initially wanted to try this product for a genetics case study I was doing in med school on myostatin’s role in muscle strength, health, size, and endurance. You may not notice a change at first, but after a few weeks you’ll notice a huge change. Very good for people who do not have generally “good” genetics.

  23. 5 out of 5

    nitroteam (verified owner)

    [Subject] Took for 90 days added quite a-bit of size while taking Rad.
    Return customer X 4

  24. 5 out of 5

    Taylor McBride (verified owner)

    Added to the lgd stack, this sarm works wonders. Did the lgd stack previously without yk11 and then this time with and it was a definite game changer. Didn’t notice much difference the first 3 weeks but weeks 5 thru 8, subject gained 10 lbs easy.

  25. 5 out of 5

    XxFaustinoxx (verified owner)

    When stacked properly, this caused an increase in gains within my test subject.

  26. 5 out of 5

    Scott Michael

    Great product! Works as described!

  27. 5 out of 5

    Aaron Abbott (verified owner)

    Do your research. Not for newbies or anyone not aware of it’s potency!

  28. 4 out of 5

    Jonathan Ludlow (verified owner)

    This was my first time using YK11 on my test subject and so stuck with 5mg per day for 8 weeks,stacked with Rad140 at 15mg per day, to check tolerance.

    [Subject] Definitely noticed joint pain in the first few weeks, which subsided gradually but didn’t notice much increase in size compared to using RAD140 solo.

    Next cycle will run at 10mg per day, again with RAD to see my [subject’s] size.

    Defo legit product based on side effects but too early to tell if I see a benefit in using long term.

  29. 5 out of 5

    Stefan Mensch

    Best stuff

  30. 5 out of 5

    Trevor Ricci (verified owner)

    Comparable to tren at higher doses. Couldn’t tire out. Turned into energizer bunny.

  31. 5 out of 5

    Samuel Downey (verified owner)

    Beast mode

  32. 5 out of 5

    Matthew Merryman (verified owner)

    Incredible with even a mild SARM (S-4) All muscles grew at least double in size, incredible strength gains in subject. 40-50lb increases on all maxes, 8 week, 15mg day dosage. Great results.

  33. 5 out of 5

    Alex Cardona (verified owner)

    Great Product!! would recommend!

  34. 5 out of 5

    Eduardo Escalera (verified owner)

    This product shows results within a couple of weeks. No side effects at all. This really compliments other muscle building sarms in test subjects.

  35. 5 out of 5

    Stefan Mensch


  36. 5 out of 5

    Eduardo Escalera (verified owner)

    Test subject got harder muscles and retained muscle gains.

  37. 4 out of 5

    Dave Bellotti (verified owner)

    After four weeks subjects showed muscle growth. One subject was on a reduced calorie diet and still made gains.

  38. 5 out of 5

    Cameron Reedy (verified owner)

    got here in 3 days best company ive bought from amazing

  39. 5 out of 5

    Brutus Blackheart (verified owner)

    Myostatin inhibitors are a wonderful supplement. Anything that minimizes Myostatin is going to increase hypertrophy and strength gains. Exact progress is hard to gauge. My test subjects will be taking varying dosage and taking at different intervals to measure improvements. In theory, a night time regimen makes the most theoretical sense.

  40. 5 out of 5

    Cameron Reedy (verified owner)

    at 10mg a day it took some time to notice results but strength increased like crazy

  41. 5 out of 5

    Adam Villalvazo (verified owner)

    great product definitely recommend it saw a dramatic change

  42. 5 out of 5

    Logan Broussard (verified owner)

    Highly recommended, subject noticed small results around 3rd week, big results at the 6th-8th week mark & at 12 weeks sustained feeling as well an improved visual of the physical body. Note: Subject had a diet plan while using supplement.

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