YK-11 SARM 101: The Bodybuilder’s Guide

YK-11 is like no other SARM. So before you even consider using this PED, you will want a perfect understanding of what it does and how it does it. Throwing YK-11 into a cycle or stack without knowing its primary purpose will only lead to disappointment and some hideous side effects to boot.

But wait, let me tell you something: You will come across a lot of negative commentary about YK-11 because this is a SARM that divides the bodybuilding community for several reasons.

I’m not here to tell you whether or not you should use it. What I will do is present all the facts and all the critical things you need to know about YK-11. The rest is up to you. Now, let’s get into it!

What is YK-11?

YK-11 is a steroidal selective androgen receptor modulator (SARM), which makes it different from most of the other modern-day SARMs used in bodybuilding and performance. But why is that? The majority of new SARMs are now non-steroidal.

YK11 is also one of the least tested SARMs, so we have hardly any data at all to go by in terms of both its measured positive effects and its short and long-term side effects. In fact, there are exactly ZERO studies or trials of either animals or humans with YK-11.

But as always, we have plenty of anecdotal and personal experiences from individuals in the bodybuilding community. These cover the spectrum of good and bad experiences and everything in between.

YK-11 History and Overview

As a steroidal SARM, YK-11 is what we’d call one of the “old school” SARMs. Steroidal SARMs have been an interest in research since way back in the 1940s^[1]. These mainly were modified testosterone hormones. Only in the 1990s did development and research on nonsteroidal SARMs start to take off, thanks to work by Ligand Pharmaceuticals.

YK-11 is actually based on the Nandrolone hormone, which is one you’ll be familiar with if you’ve ever used or had an interest in anabolic steroids. This essentially makes it a 19-nor steroid.

As if that’s not enough… While it is still an SARM, you will see YK-11 also being called a myostatin inhibitor. As a protein that will hamper muscle growth, inhibiting myostatin is desirable for gaining muscle and doing so at a high rate and quickly.

Unfortunately, YK-11 is no longer in research, falling out of favor with more modern nonsteroidal SARMs. There’s also no data from any studies besides those on cells, making this one of the more mysterious SARMs, at least in terms of official scientific results.

Mechanism of Action

YK-11 helps remove a limitation to building muscle: Myostatin. Myostatin is a protein found exclusively in the skeletal muscle and is known to inhibit muscle growth.

YK-11 is able to inhibit myostatin itself, removing this natural barrier to more muscular growth. This makes YK-11 a PED that won’t directly stimulate much muscle growth on its own.

This is the key reason YK-11 is so often used in combination with a SARM that facilitates direct muscle growth, allowing YK-11 to remove limitations to making more significant gains (myostatin).

Effects of YK-11 (Benefits)

YK-11 is a true performance SARM and one that appeals to some steroid users. For that precise reason, people who prefer only to use SARMs (and not steroids) will often choose never to use YK-11 at all because of its potency.

But for those who do, some potent effects can be experienced. And most of these will only be realized at their full potential when you’re using injectable YK-11. These include:

Muscle Mass Gains

YK-11 can support some nice muscle gains when used on its own, but when it’s stacked with any other PEDs (as it often is), it’s going to boost their anabolic effects substantially as well due to the inhibition of myostatin.

This can make it difficult to know how much muscle can be gained with YK-11 alone (remembering that we have zero clinical studies). Stacked cycles with RAD-140, for example, can see you gaining up to 20 lbs in body weight.

Dry and Hard Gains

YK-11 will dry out your physique and increase muscular hardness. Often called a “3-D appearance” – very defined, blown up muscles with no water retention.

Two steroids I often compare YK-11 to are Winstrol and Masteron, so if you’re familiar with what those can do to the physique, you’ll understand how YK-11 can deliver in this area of effects.

Pumps

Many users will talk about super powerful pumps with YK-11 along with general muscle fullness. Pumps can be intense; the higher your dose, the more you can expect your pumps to ramp up. This is one of the most confronting and noticeable effects of YK-11 and will be even more pronounced when stacked with something like RAD-140.

More Strength

YK-11 will give you a massive strength boost. This is one of the effects that you’ll hear users raving about the most. Something that can and will reduce your strength gains on a YK-11 cycle, though, is testosterone suppression, so you should prioritize controlling suppression if you want to maximize strength gains. Your lifting ability will improve noticeably throughout the cycle, allowing you to break through personal bests and plateaus.

Faster Recovery

YK-11 is known to speed up recovery as well or even better than any other SARM. This means less muscle soreness after working out and the ability to work out the same muscle groups with less downtime in between sessions.

YK-11 Dosing and Administration

The way you dose and administer YK-11 is going to depend on what your preferred form of this SARM is:

• Liquid
• Injection
• Capsules

The low oral bioavailability of YK-11 compared to other SARMs makes this one that is not at its best when taken orally (liquid or capsule). You’ll get better results and possibly fewer side effects when using injectable YK-11 at low doses compared to high-dose sublingual administration.

Doses

Doses of YK-11 will depend on whether you’re taking the liquid oral solution or if you’ve decided to do YK-11 injections. This is very important: Injectable YK-11 requires a lower dose than oral.

An oral starting dose will usually be around the 10mg daily mark, but 10mg is quite a high dose for injecting YK-11. The dosages below are based on injecting YK-11, as it’s this method that will provide the very best effects and results with this SARM:

Beginner

5mg is a solid introduction to YK-11 and lets you get a feel for its positive and negative effects without going overboard. Joint pain should be minimal at this dose, but suppression is still an issue and will require PCT and, ideally, on-cycle support.

Intermediate

10mg daily taken 5mg morning/night. This dose will noticeably improve your strength gains but is also likely to crash your testosterone. If you weren’t already using a testosterone or SERM base on-cycle at 5mg (recommended), you’d certainly need it at 10mg. Muscle hardness will be impressive at this level, and you should start experiencing some big pumps.

Advanced

The most advanced users are known to inject 15mg daily (if taken orally: 30mg). At this dosage, testosterone shutdown is likely, and you will also be looking at stacking YK-11 to take advantage of the myostatin-inhibiting effects to boost the lean mass gains of other compounds rather than relying on excessive doses of YK-11.

Female

YK-11 use is rarely reported by females as other SARMs are better suited to female athletes. Women who want to attempt using YK-11 should do so at the lowest dosage range, 0.5mg to 2mg, to evaluate their response and side effects.

Bioavailability, Half-life, and Cycle Length

Although we have no human (or animal) studies to back this up, it has become well-known that YK-11 has poor bioavailability when taken orally (the way almost everyone takes most other liquid or capsule SARMs).

So, what does this mean in the real world?

This means it isn’t absorbed and used by the body efficiently. If you take oral YK-11, your dose will need to be higher than if you’re injecting. Many YK-11 users inject it at a low dose of 5mg to 10mg daily and see excellent results.

The half-life of YK-11 is still up for debate. Suggestions of anywhere from 4 to 12 hours are common – because no one knows.

But get this:

4-8 weeks is the recommended length of use of YK-11, which also applies if it’s included as part of a stack. Plenty of guys will want to stop at the 4 to 6-week mark because this is such an intense SARM to use, and going to 8 weeks is not always necessary or desirable if you’re finding the side effects difficult to deal with.

Dosing Schedule and Administration Methods

I’m sure you’ve noticed that almost all SARM users take their dose orally using a liquid product. YK-11 is, again, a little different.

Yes, it can be bought as a liquid like any other SARM. But many will argue that due to YK-11’s very low bioavailability when taken orally, it’s not even worth taking that way.

That leaves one other option to boost bioavailability: injecting. But for a lot of SARM users, the big appeal is NOT having to inject, making it one of the leading reasons SARMs are often chosen over steroids.

OK, I know what you’re thinking: Should I bother using YK-11 at all if I don’t want to inject? Many still take it orally, but as I’ve mentioned, you will usually need a higher dose to see worthwhile results.

Now, this is a critical thing to know if you’re going down the injecting path: Don’t just inject liquid YK-11 from the bottle of regular SARMs. You will need to buy the specific injectable form of YK-11, which has been formulated to inject by placing the YK-11 into a carrier solution such as MCT oil. Administration of YK-11 injections should be the same as anabolic steroids, with all hygiene precautions taken.

Taking YK-11 at least twice daily is the best approach, given its half-life is likely under 12 hours. Many will take it as a pre-workout and find it provides a very noticeable boost to strength and performance.

YK-11 Cycles

Anyone with PED experience will tell you very clearly: if you’re going to use YK-11, you should think of it as a steroid, which means running a testosterone base.

Now, that will turn away anyone who isn’t keen on injecting anabolic steroids (a lot of SARM users). So, can you stack YK-11 without a testosterone base? Yes, but prepare yourself for the inevitable suppression that will occur.

Alternatively, we can use Nolvadex or Clomid in place of a testosterone base. This is the option most users take, and it can effectively support the high-level suppression caused by YK-11.

YK-11 Cycle for Men

What you read and hear from men who run a YK-11 cycle can vary from the mediocre and unenthusiastic right up to the guys who will swear that YK-11 is as powerful as some steroids.

Why the difference in experiences?

The main reason is that oral YK-11 has such low bioavailability that it’s rarely going to be able to support the same level of results that you can get when injecting YK-11 (not everyone is aware of this).

Then there are the common complaints of joint pain that some, but not all, users will suffer with at some point on a YK-11 cycle. At a 15mg dosage for eight weeks, men will typically find that side effects like joint pain are minimized while effects are still exceptional.

Results to expect include:

• A hard, dry physique
• Muscle gains of up to 15lbs (potentially more)
• Loss of body fat in the 5-10% range, depending on your current body fat levels.
• Strength through the roof

Positive comments and reviews from men on YK-11 cycles always focus on the strength gains and the muscle hardness, and many will mention intense pumps. But the negatives will also go down that same road: with similar effects to steroids come the similar potent side effects.

There are also more than a few other negative comments out there about a range of bad experiences with YK-11:

• Issues caused by suppression, like low energy, when measures aren’t taken to provide testosterone support.
• Depression and other mental issues (which also might or might not result from failing to maintain testosterone levels).
• Aggression and irritability.
• Some guys complain that YK-11 doesn’t do much; almost certainly, they are taking it sublingually and experiencing its poor oral bioavailability.

Reviews and comments about YK-11 often compare it to steroids.

Guys who have a history of steroid use don’t shy away from stating that YK-11 is as powerful or even more so than steroids like testosterone taken at performance doses. That tells all we need to know about just how incredibly powerful YK-11 is!

YK-11 Cycle for Women

Due to its steroid-like effects, YK-11 is not known to be used by women very often. There are FAR more appropriate and better-tolerated SARMs (and even steroids) for women, so a female would need a very good reason to want to use YK-11.

Females can expect similar results to men who use YK-11: increased strength and muscle gains, faster recovery, and some fat loss.

Females will require a very low dose of YK-11 to experience its effects: as low as 0.5mg daily may help avoid the worst of side effects, but with so few anecdotal experiences being shared, women may suffer with side effects that we aren’t expecting from this SARM.

Due to the lack of known use of YK-11 among females, very few anecdotal experiences are available of either positive or negative experiences from women who have run a YK-11 cycle.

YK-11 vs. Other PEDs

As a powerful bulking SARM, it makes sense to compare YK-11 to other SARMs that are primarily used for gaining muscle (although many also have other additional benefits). So, I want to briefly compare YK-11 to two of the SARMs that people most often ask about in terms of comparing benefits and results.

YK-11 vs. RAD-140

There are plenty of reports out there of guys stacking these two powerful SARMs. Just be aware that this will result in almost or total testosterone shutdown (among other things).

But what if you want to put YK-11 and RAD-140 side by side and decide which ONE to use on its own? Here are the main points of similarity and difference between RAD-140 and YK-11:

• RAD-140 is a nonsteroidal SARM, while YK-11 is steroidal.
• Both are suppressive, with YK-11 being more suppressive than RAD-140.
• Both will promote muscle gains, but RAD-140 does it directly and much more powerfully.
• Both will boost muscle growth, strength, bone density, and recovery.
• Both can impact liver and cholesterol values.
• RAD-140 is known to cause hair shedding, much more so than YK-11.
• Both are dry compounds with no water retention.
• RAD-140 is versatile enough for bulking, cutting, and recomp cycles, but YK-11 is primarily used in bulking and strength cycles.

These two very different PEDs have differing mechanisms of action, resulting in entirely different ways of building muscle and other effects.

YK-11 vs. LGD-4033

These two bulking cycle candidates are powerful but go about things very differently.

Purely from a muscle-building and aesthetic perspective, LGD-4033’s water retention provides additional challenges if you’re looking for a hard, toned physique. Still, with the right approach, this can be managed well.

• Both will suppress testosterone.
• LGD-4033 has a longer half-life and can be taken once daily.
• YK-11 is the better strength booster.
• LGD-4033 users typically find recovery times superior to YK-11.
• LGD-4033 is thought to pose less of a risk to the liver.

In short, LGD-4033 is a bulking SARM, while YK-11 can be thought of more as a strength SARM when used on its own. The real power and skill are found in combining these two in a stack and reaping their benefits.

Stacking YK-11

Stacking YK-11 is the best way to use it because it’s going to act as a booster for the muscle-building effects of the other PEDs in the stack.

How does it do this?

By inhibiting the protein myostatin. So, there’s an excellent opportunity for synergy when combining YK-11 with powerful bulking SARMs like RAD-140.

YK-11 + RAD-140 (Bulking Stack)

This is the most common YK-11 stack you’ll see talked about. It’s a hardcore bulking and strength stack with two of the most potent SARMs. In other words? Not for beginners! Get a good amount of experience with both before even thinking of running this stack.

Benefits

• Big strength increase
• Huge lean muscle gains
• Big pumps
• Dry, hard, and vascular
• Increased aggression (many see this as a positive)
• Fast recovery times

Dosing

• YK-11: 10mg daily
• RAD-140: 10mg daily
• Recommended: 10-20mg of Nolvadex daily on cycle to combat suppression.
• Cycle length: 8 weeks

Possible Side Effects

• Testosterone suppression
• Liver and cholesterol stress
• Joint pain
• Hair shedding

Results

With both these SARMs being what we call dry compounds, you won’t be weighed down with water retention. Muscle gains of 15lbs+ will be lean gains and should be well maintained after your cycle IF you ensure actions are taken to maintain testosterone levels both during and after the cycle.

PCT

Nolvadex 30mg for three weeks, then 15mg for the final week.

YK-11 + Stenabolic (Recomp Stack)

I want to go against the grain a little here and move away from pure bulking stacks to what we could call more of a recomp stack with the addition of Stenabolic. Stenabolic is not a SARM but a Rev-ErbA agonist, so these two compounds have very different mechanisms of action without overlap. Just like YK-11, Stenabolic has low oral bioavailability, and many users will instead choose to inject it.

Benefits

• Increased endurance
• Cholesterol support from Stenabolic
• Fat loss
• Some dry lean gains
• Dry and lean physique with increased definition
• Muscle preservation if you’re in a calorie deficit
• Strength maintenance

Dosing

• YK-11: 10mg daily
• Stenabolic: 20-30mg daily
• Cycle length: 8 weeks

Possible Side Effects

• Testosterone suppression
• Possible liver stress
• Insomnia

Results

A complete body recomp is possible in just eight weeks on this cycle. With Stenabolic boosting endurance and YK-11 supporting your strength and muscle preservation, this underrated combination provides impressive body transformation.

The main downsides are the short half-life and multiple daily injections of both these PEDs; ideally, YK-11 should be administered twice daily and Stenabolic up to three times daily.

PCT

Four weeks of Nolvadex: 40mg/daily for the first two weeks, 30mg/daily for week 3, and 20mg/daily for week 4.

YK-11 + MK-677 (Bulking Stack)

This is a stack focused on bulking as well (because YK-11 is best at making it easier to gain muscle above all else). MK-677 will boost your appetite and make it possible to eat the calories you need to get the gains you’re aiming for.

Benefits

• Significant muscle gain
• Increased appetite
• Great pumps
• Big strength
• Fast recovery
• Improved sleep quality

Dosing

• Weeks 1-8: YK-11 10mg/day, MK-677 25mg/day
• Weeks 9-12: MK-677 25mg/day
• Weeks 9-10: Nolvadex 40mg/day
• Weeks 11-12: Nolvadex 20mg/day
• Cycle length: 12 weeks

Possible Side Effects

• YK-11 is a dry compound, but MK-677 can cause some water retention.
• YK-11 is suppressive, so PCT is required (see below).
• Possible increase in blood sugar levels.

Results

Muscle gains of up to 15 lbs are possible. YK-11 will help offset some of the water retention of MK-677, but you can also reduce it further by minimizing sodium in your diet and drinking plenty of water. Significant gains in strength can be expected, and you can break through personal bests lifting weights.

PCT

We continue using MK-677 for an extra four weeks due to its benefit of acting as PCT support. A Nolvadex PCT should also be run because while MK-677 isn’t suppressive, YK-11 will cause significant suppression.

YK-11 PCT

You should think about PCT from the start of your YK-11 cycle. And I don’t just mean the “post cycle” part of PCT because you’ll almost always want testosterone support on cycle as well when using this suppressive SARM.

Stacking YK-11 with another suppressive PED? Don’t even think about not using a testosterone or SERM base for support on-cycle. So, for your entire YK-11 cycle, I recommended taking either of the following:

• Enclomiphene at 12.5mg daily, or
• Clomid at 25mg daily, or
• Nolvadex at 10mg daily

This will ensure you don’t fall into a debilitating state of low testosterone while on cycle. Continue with your chosen SERM for the actual PCT for another four weeks at the end of your cycle.

YK-11 Side Effects

YK-11 is a potent compound, so you can expect to be dealing with some pretty harsh side effects (especially if taking higher doses above 5mg daily), such as:

• Testosterone suppression
• Joint pain and stiffness
• Liver issues
• Hair loss
• Negative cholesterol changes

Other side effects that are often reported anecdotally (and not necessarily experienced by all YK-11 users) include increased aggression, acne, and insomnia.

Testosterone suppression

Suppression on YK-11 can range from moderate to severe or even total shutdown. Stacking with any other suppressive compound will likely result in a complete shutdown, so PCT should always be a part of your YK-11 cycle planning.

Most men will want to run a testosterone base with YK-11, but this could also mean just using a SERM like Nolvadex throughout the cycle.

Joint pain and stiffness

Myostatin inhibition can cause stiffening and pain in the joints, which in turn can impede your strength as you begin to have difficulty with a full range of movement.

Some users will find that joint pain becomes severe as early as the first week of a YK11 cycle. This can include just about any joint in the body: elbows, knees, shoulders, and even the fingers. Lowering the dosage to 5mg can help reduce joint-related side effects.

Liver

Both oral and injectable YK-11 can potentially stress the liver. The injectable form is thought to be less toxic to the liver, but we lack any scientific evidence as to how much stress YK-11 places on the liver. This is another good reason to keep up with your bloodwork before, during, and after your cycle. In any case, on-cycle liver support (such as NAC and milk thistle) is highly recommended.

Hair Loss

Hair shedding or loss is a side effect that is heavily individualized. Some users will see no issue, but others have noted severe hair shedding. You won’t know whether you’re affected by hair loss with YK-11 until you start using it.

Interestingly, some guys who have tried both oral and injectable forms of YK-11 have noted that the oral form causes MUCH more hair shedding. In contrast, minimal hair loss was experienced when injecting YK-11.

Cholesterol

YK-11 will cause some negative cholesterol changes to LDL and HDL levels. You’ll need bloodwork to confirm just how serious this side effect presents itself, especially as you’re unlikely to feel any different even with significantly elevated cholesterol levels.

Where to Buy YK-11?

Buying YK-11 is something most of us find very easy to do online. Where you live (country) will affect how much you pay and if there are any complications in ordering SARMs. For most countries, including the US, it’s a stress-free process.

So, where to buy it? Here are my top picks:

Availability of YK-11

Even though YK-11 is based on a steroid and acts much like a steroid, it’s still a SARM and is easily purchased via the usual SARM suppliers where you’d buy nonsteroidal SARMs. So you won’t have any issues finding YK-11 via the very same methods you might have used to buy RAD-140 or any other popular SARM.

If you’re planning to inject YK-11, you’ll need to look specifically for injectable YK-11 products. Only relatively few suppliers are selling injectable SARMs, as most people still prefer to take liquid. Capsule YK-11 is also sold.

Whichever type of YK-11 you prefer, online availability is widespread and accessible.

Is YK-11 Legal?

Even though YK-11 is so closely related to steroids, it’s still categorized as a SARM, and so it falls under the same research chemical class as all the other SARMs you know and love. This makes it easy to buy and use as a bodybuilder for personal use.

Online research chemical sellers are legally allowed to sell their products as long as they’re sold with the disclaimer that the SARM is for research purposes only. Should you be worried about this? What if you’re not a researcher? Well, most of us aren’t researchers (besides “researching” our own strength and muscle gains).

But don’t worry: for now, no authorities are checking who is using SARMs and why, so they don’t come with the legal worries that we have when buying and using anabolic steroids.

But what about if you’re a competitor or professional athlete? YK-11 is classified as a prohibited drug by WADA and all sporting authorities around the world. It’s considered a performance-enhancing drug like anabolic steroids are, and drug testing will target the use of all SARMs.

Typical Pricing

You should be able to find YK-11 at prices that are similar to those of most other SARMs. Liquid, injectable, and capsules are available from all the top online research chemical sellers. You can also find YK-11 powder, although few of us will go down that path due to the complications in measuring out accurate doses and administering powder.

• Liquid YK-11 typically comes in a 30ml bottle, dosed at 10mg/ml concentration. Expect to pay around $60 per bottle.
• Injectable YK-11, where the solution is suspended in a carrier oil ready for injecting, typically comes in 10ml vials priced between $60 and $100.
• Bottles of 60x5mg YK-11 capsules can be found for around $60.

Most sellers provide an online certificate of analysis, showing lab results from a third-party testing company certifying the purity of the formula.

Final Thoughts

The big question with YK-11 is: Do the benefits outweigh the risks? This isn’t something we are so concerned about with most other SARMs because none are as closely related to steroids as this one is.

And it’s a question that ultimately only YOU can answer. If you’re used to using or just learning about SARMs, you need to change your mindset when it comes to YK-11 and think of it as a steroid.

And I’m with a lot of other guys on this one: YK-11 is best used as an injectable. If you don’t want to inject? You can still definitely get some benefits with it orally, but there are better options in the world of SARMs if you want to stick with orals.

Related:

• Ostarine (MK-2866) 101: The Complete Guide
• Cardarine SARM 101: The How-To Guide to GW-501516
• S23 SARM 101: The Bodybuilder’s Guide

— Furious Joe