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What is YK 11?
YK-11 is possibly the most powerful selective androgen receptor modulator (SARM) currently on the market. But it is different from other SARMs such as MK-2866, RAD-140, and Ligandrol (LGD-4033) in a few ways.
First of all, its the only modern SARM which has a steroidal molecular structure. As a matter of fact, it closely resembles the structure of DHT (Dihydrotestosterone), an endogenous androgen sex steroid and hormone, that is a by-product of testosterone.
Secondly, it is the only SARM that acts as a myostatin inhibitor.
Yk11: A SARM or steroid
There is some debate about the question if YK-11 should actually be considered a SARM. After all, all of the other modern SARMs are non-steroidal.
All, except YK-11, which is a steroidal SARM, closely related to DHT.
But unlike steroids, YK 11 binds to the androgen receptors in a tissue-selective manner, which is sort of the definition of a SARM.
YK 11: a myostatin inhibitor
Most of the products that claim to inhibit myostatin fail to do so effectively or at all. Research has shown YK to have the ability to increase follistatin in much the same way as DHT does.
Follistatin is a naturally occurring protein in the human body which helps keep myostatin in check. Myostatin limits muscle-growth. Follistatin levels inhibit myostatin levels which increases muscle mass.
How does YK11 work?
Of all the SARMs currently on the market, YK11 has the least research data. There is no clinical data on this compound, nor have there been any animal studies.
Most of what is known about the way that YK11 works, is based on the available research on a cellular level. Because of the popularity of this compound among bodybuilders, there is a fair amount of user reports.
YK-11 and selective tissue binding
Similar to other SARMs, YK11 binds to the androgen receptors in a tissue-selective manner. Because it binds to the androgen receptors in skeletal muscles it has strong anabolic properties, comparable to that of androgenic anabolic steroids.
YK-11 Myostatin inhibitor
Some of the basic research mentioned consisted of cellular testing in order to find out about the basic method of action. The results show that YK 11 primarily aims to increase follistatin levels.
Follistatin is naturally occurring protein in the human body which helps keep myostatin in check.
When follistatin is raised, myostatin level is inhibited. Inhibition of myostatin results in increased muscle mass and improved strength.
The pros and cons of YK 11
So far, the only studies this SARM has seen are cellular ones. There have been no studies on humans or even on animals. Most of what we know about the benefits and side effects of YK-11 is based on anecdotal evidence and user reports.
This study shows that mice that have low levels of myostatin have twice the amount of muscle mass compared to mice that have high levels of myostatin.
Some of the benefits associated with the use of YK11 include:
- Increased muscle growth
- Improved fat loss
- Increased strength
Increased muscle growth
The most obvious benefit of YK11 is without a doubt rapid muscle growth. YK11 is able to drastically improve muscle growth and produce new muscle cells. It does this by naturally increasing follistatin cells, whilst suppressing myostatin (a protein that stops excessive muscle growth).
Reports of 6 to 8 kg of increased muscle mass from an 8-week cycle are not uncommon.
Improves fat loss
Fat loss is one of the major advantages that YK-11 has to offer over most other SARMs and steroids. YK-11 focuses on replacing any excess fat mass with solid, strong muscle mass – one that you can be proud of.
The goal of YK-11 is not to pump your muscles but also to make them stronger. Through the production of follistatin, YK-11 works to strengthen your muscles, making them stronger than ever.
YK-11 Side effects
Because there aren’t any studies on the safety of YK11 use in humans, we have to rely on user reports for info about the possible side effects of this SARM.
While most users report little to no side effects, others report quite a lot of unwanted side effects. The conclusion is that the side effects vary from person to person.
Some of the protentional side effects associated with the use of YK-11 are:
- Testosterone suppression
- Mild liver toxicity
- Increased aggression
- Joint and tendon pain
Most SARMs will lead to the suppression of natural testosterone production, and YK-11 is certainly not an exception in that regard. Based on anecdotal evidence and user reports it is safe to conclude that YK 11 is more suppressive than other SARMs.
YK 11 certainly justifies the use of a PCT (Post Cycle Therapy) after a cycle.
YK 11 vs RAD 140
As the title as this post already revealed, YK 11 is more than just a SARM. The steroidal structure and the fact that it acts as a myostatin inhibitor makes this SARM unique.
But how does it compare to the strongest non-steroidal SARM: RAD 140 (Testolone). We will provide a comparison based on several aspects.
YK 11 vs RAD 140 – half-life
When we look at the half-life of these two SARMs, RAD 140 vastly outperforms YK 11.
The YK 11 half-life is just 12 hours, which means that it has to be taken twice a day to get the full benefits.
In contrast, RAD 140 has a half-life of 44 hours, so you only have to take it once a day or even once every other day to stabilize blood concentration level.
YK 11 vs RAD 140 – benefits
If we look at the results in terms of strength and muscle mass, YK 11 is without a doubt the stronger of these two SARMs.
However, if we focus on fat loss and vascularity, RAD 140 is the superior one.
YK 11 vs RAD 140 – side effects
Where it concerns side effects, the most powerful compound usually has the most of them. And when comparing YK 11 with RAD 140 this is holds true:
- YK 11 is more suppressive than RAD 140, which shouldn’t come as a surprise given the steroidal nature of this SARM.
- Because YK 11 has a methylated group added to it, it puts more strain on the liver. With this compound, it doesn’t hurt to take some liver support such as Milk Thistle during the cycle.
YK-11 dosage and cycle length
YK-11 is effective in dosages as low as 5mg per day. The most common dose for increasing muscle mass is 10mg per day, taken over a period of 6 to 8 weeks.
Because YK 11 has a relatively short half-life of 12 hours, it is recommended to split the dose in half: 5mg in the morning and 5mg in the evening. Some bodybuilders will stack YK-11 with other SARMs like MK-677 or RAD140.
How to dose liquid YK 11?
Measuring the correct dose of liquid YK-11 is a very easy process. For more information check out our article: How to measure and dose liquid SARMs?
Where can I buy YK-11?
Frequently asked questions
Is YK11 legal?
At this moment, YK-11 is legal in almost every country around the world, with the exception of Australia. However, as it is not approved for human consumption, it cannot be sold as a supplement in most countries. But it can be sold for research purposes.
What is the half-life of YK11?
The half-life of YK 11 is roughly 12 hours. Therefore, it is usually divided into several portions during the day.
Does YK11 cause hair loss?
Because there have not been any human studies on the use of YK11, there isn’t much info about the side effects. There are however cases where users complained about hair-loss.
What are the YK 11 side effects?
The side effects of YK 11 include testosterone suppression, mild liver toxicity, increased aggression and joint and tendon pain.