Last Updated: Nov 27, 2020
SteroidCycle.org is intended for informational purposes only and does not take the place of professional medical advice.

Ostarine is known under several names including Enobosarm and Ostabolic, and its chemical code of MK-2866. This SARM is a powerful anabolic compound that can provide some similar benefits to those of anabolic steroids but without the very serious side effects.

Ostarine is a versatile compound that can do whatever you want it to. Want to make some nice mass gains? Ostarine can do that. Or perhaps you’re ready for another cutting cycle and need something to help maintain your lean muscle and give you a hardened look without water retention? Ostarine can do that too.

This makes MK-2866 a SARM that can suit a wide range of people, and not just those looking to pack on muscle mass. Its anabolic effects make Ostarine a compound that’s not only useful on its own, but one that can also be utilized by steroid users who want to take an extra step in retaining muscle gains in between steroid cycles by using a milder yet still very effective substance.

My Ostarine cycle guide has been broken down into the following sections:

What is MK-2866 (Ostarine)?

It is useful for both bulking and cutting. It has direct anabolic effects by binding to androgen receptors only in the muscles and bones, and because it doesn’t aromatize or convert to estrogen or DHT like real steroids do, we can get the full benefit of anabolism where it’s needed without the dreaded adverse effects that anabolic steroids cause.

That doesn’t mean Ostarine can’t cause side effects and as we will see, one of those is the mild suppression of testosterone in some users but overall we can use Ostarine with the confidence that the most harsh effects of anabolic steroids won’t be experienced. And this also make Ostarine very useful to female users equally as to men.

This is what makes SARMs like Ostarine so appealing to athletes, bodybuilders and anyone wanting a performance increase or physique improvements.

Ostarine can achieve its muscle building ability through much of the same processes that are also stimulated by steroids; after all, these are the core biological functions of muscle growth. This includes protein synthesis and nitrogen retention which will both be enhanced by Ostarine.

With such a wide range of uses it is little wonder that Ostarine is a popular SARM that is delivering impressive results for many different people.

Editor’s Note: For real, NO-BS information on cycling steroids be sure to check out Straight From the Underground (my recommended underground steroid handbook). Everything in this book is based on first hand experience, not theory.

If you decide to try Ostarine I recommend buying it here.

MK-2866 Benefits (Effects)

Ostarine delivers some similar benefits and effects to steroids, by operating in a slightly different way to achieve the same goals and with the bonus of not causing the same adverse effects at the same time.

While no substance can rival the sheer power and potency of the best anabolic steroids when it comes to increasing muscle, strength and performance, Ostarine is no slouch and the majority of users will be able to see impressive benefits and effects with this SARM.

In addition to increasing the critical processes of nitrogen retention and protein synthesis, it has been shown that Ostarine can also boost IGF-1 (insulin-like growth factor 1) which will contribute to greater strength and muscle gains. These processes combine to give Ostarine similar functionality to steroids.

These are the main benefits and effects you are likely to see with Ostarine:

Lean Muscle Gains

This is probably the main reason you are considering using MK-2866, and with good reason. The evidence is clear that Ostarine promotes the growth of lean muscle. You won’t be gaining the same level of mass as with steroids, but these quality gains are more than impressive and come without any fluid so there’s no masking of your gains with fluid, bloating or gyno.

Muscle Recovery

By targeting muscle tissues MK-2866 stimulates the repair of muscle after intensive exercise. The faster you can recover, the quicker you can get to your next workout and get those gains happening faster.

Bones

Ostarine improves bone health by enhancing bone mineral density which strengthens bones and protects against fractures. The small amount of estrogen that MK-2866 can cause an increase of is not something men should be concerned about, as it is critical for bone health and this low level.

Joints

Ostarine can bring about a slight increase in estrogen, and while this might raise alarm bells in male users, it should not because it is not caused by the process of aromatization (where testosterone is converted to estrogen), and this small increase in estrogen in males can bring some excellent benefits.

One of those is improvement in joint health which is highly beneficial to any bodybuilder or athlete as Ostarine will assist with the repair and healing of joints. This is going to help you train harder and also provide an important advantage when you’re on a restrictive cutting diet where some people can have discomfort of the joints.

All users regardless of goals will benefit from strengthened joints which is the basis for your movement whether it’s lifting weights, running, competitive sports or any other activity.

Heart

There’s some early evidence that Ostarine could have the potential to assist with heart health in those existing heart disease by reducing lipid levels. However much more research would need to be undertaken in this area and it is unlikely to be a benefit that is of much concern to those using MK-2866 for performance enhancement purposes.

Bodybuilding Benefits

Boosting anabolic activity is what Ostarine is designed to do. Similarly to steroids, this SARM will increase protein synthesis and nitrogen retention plus has the benefit of enhancing healing and joint health (a positive effect from its goal of treating osteoporosis). This aids in recovery and also allows you to train longer and harder with stronger joints and ligaments increasing your tolerance and ability for more intensive training.

Because of Ostarine’s specific targeting of muscle and bone tissue and thanks to its ability to both grow and preserve muscle it is able to be used for both bulking and cutting. Retaining existing muscle while cutting is an ongoing challenge for any bodybuilder and Ostarine provides an alternative to harsh steroids in achieving this goal.

Ostarine helps keep the body in fat burning mode with this retaining of muscle tissue, making fat loss easier than if you were to lose your muscle and negatively impact the metabolism. When we talk about Ostarine promoting anti-catabolism in the body, this is the core effect and it clearly makes this SARM very ideal for cutting purposes.

Those wanting to use Ostarine for bulking will see excellent lean muscle gains without the concern of water retention and gynecomastia which are estrogen related side effects of steroids. This means all the gains you make when using Ostarine are high quality muscle gains (provided your diet is correct) rather than some gains being masked by water retention which is a major issue with many anabolic steroids.

The effect of Ostarine and other SARMs on cholesterol are still mostly unknown. One study in 2008 using Ostarine noted a decrease in cholesterol levels among the study participants. With such little data available though it is unknown one way or the other whether Ostarine can positive or negatively impact cholesterol, or whether the effects vary widely between individuals.

MK-2866 (Ostarine) Dosage

Ostarine’s half life is about 24 hours so you can safely take your dose once a day and know that blood levels of the compound will remain at a prime level during that time. Depending on your dose, some users on higher doses may choose to split the dose into a twice daily administration so half is taken early in the day and the remaining half at evening time.

Ostarine is easy to take as its an oral SARM so no injections are required.

Studies have discovered that even very low doses of Ostarine (1mg daily) can increase muscle mass in people with muscle wasting conditions. As these are people with already very low levels of lean muscle, bodybuilders wanting to take muscle growth to more extreme levels will look at taking a higher dosage, but those who are just starting out or who only want mild gains can safely start at this low dose and know that it has the potential to bring about some gains.

For a cutting phase where you need to retain muscle while on a reduced calorie diet, a dosage of Ostarine at 15mg daily is recommended. This dose helps protect muscle but does not, in most people, promote much growth.

To achieve muscle growth increasing the daily dosage to 20mg or up to 25mg is standard for most people, and while high doses can be used it is thought that the benefits do not increase noticeably above 25mg. A simple 6 to 8 week cycle will require some post-cycle therapy (PCT) afterwards by some men, while others won’t suffer any suppression at all. In any case a minimum of 4 weeks with a break without any SARMs is always needed for recovery.

For performance enhancement, a good dose to start at is 15mg per day. This will provide more than enough to deliver excellent results for the majority of users. But those wanting to go to the next level will look at increasing the dosage to even double that amount, at 30mg daily. It is generally thought that higher doses don’t deliver great benefits, and that somewhere between 20mg to 30mg is the sweet spot for Ostarine in male users.

Females can make good use of Ostarine without the concern of virilization and most women will look at dosing MK-2866 at 5mg to 15mg daily at the high end. Even at the lowest doses females are certain to see very noticeable benefits because of Ostarine’s high anabolic effects.

Typical MK-2866 Cycles

The typical length of an Ostarine cycle is between 6 and 8 weeks, although some users will choose as short as 5 weeks. Keep in mind that the longer your cycle goes for (and higher the dosage) the more suppression of testosterone you will likely be dealing with both during the cycle and once it’s finished.

Following an Ostarine cycle it’s important to have a break from using any SARMs at all for at least 4 weeks so the body has time to recover.

MK-2866 only cycle

It’s not unusual to do an Ostarine only cycle and it’s possible to make some nice muscle gains, especially if you are relatively new to bodybuilding.

Those who are already bulked up will likely look at other compounds for increased bulking, but can make excellent use of Ostarine to retain the gains that are made during a more potent bulking cycle. This is where the value of MK-2866 is for some advanced users: as a bridging and maintenance compound, especially after using steroids for bulking. A dosage of 20mg daily for 3-6 weeks will provide good protection of lean muscle.

MK-2866 bulking cycle/stack

To power right into a bulking cycle with Ostarine, which works very well as a sole compound for this purpose, you can take 20-25mg a day and see the benefits quickly. New users might hesitate at starting at this high of a dose, so even 10mg will still provide very noticeable gains.

But there is no doubt that a dose of up to 25mg for 6 to 8 weeks is going to show you the power of Ostarine for mass gains as it boosts strength, protein synthesis, stamina and energy so your body is primed for muscle growth and you’re going to be able to work out harder – speeding up those gains even more. There will be no water retention so expect the gains to be high quality and easier to maintain.

MK-2866 cutting cycle/stack

Ostarine can work well on its own in a cutting cycle and is superb for muscle preservation. To help retain muscle a dosage of just 15mg daily is often sufficient, as you are unlikely to be wanting to put on a lot of mass at this time. But to take fat burning to another level in a cutting stack you will want to combine Ostarine with at least one other compound that has more potent fat burning ability and one of the best choices is Cardarine.

While it isn’t itself a SARM, Cardarine is excellent for boosting energy and promoting fat burning. This powerful combination is good at preserving muscle while fat is coming off that it’s even possible to make some muscle gains while cutting, depending on your training. A 6 week cycle will deliver results, with a 10mg daily dose of each compound for the first two weeks, increased to 20mg daily for the final four weeks.

Stacking MK-2866

Using Ostarine only is very common, but its versatility can make it possible to use in stacks and in some more creative ways, such as as a bridging compound in between steroid cycles to help you maintain gains because of its minimal suppression and excellent muscle maintenance ability.

As mentioned in the recommended cutting cycle above, Cardarine is a perfect pairing with Ostarine for the purposes of obtaining a very toned, cut physique without losing muscle on a calorie deficit diet. LGD-4033 (Ligandrol) is also commonly stacked with Ostarine for the purpose of gaining muscle and retaining muscle after a bulking cycle.

MK-2866 Post Cycle Therapy

Every individual using Ostarine will need to evaluate what impact it has on testosterone. Some will experience more suppression than expected, but some guys will not suffer from any noticeable suppression. The higher your Ostarine dose, clearly the higher your risk of suppression is going to be and as a result your requirement to do PCT after the cycle.

The need for PCT for Ostarine cycle depends also on another factor: which, if any, other compounds are used in the cycle and what sort of suppressive effects they also have. If any other hormone suppressive compound is being stacked with Ostarine then the combination of both their effects will almost certainly require you to do post cycle therapy if you are to avoid a low testosterone state and the associated loss of muscle, fat gain, low energy, low libido, depression and a host of other impacts that you’ll experience if your testosterone is below normal levels.

MK-2866 vs Other SARMs vs Steroids

Ostarine is one of several SARMs that are now valued by athletes, despite the fact they are also illegal to use just like steroids are. This puts all SARMs and steroids in the same category when it comes to the law, and the same precautions are required when buying and using them.

When it comes to functionality compared with other SARMs, Ostarine has its specific advantages and these mostly revolve around muscle preservation. While it is useful for gaining muscle, some other SARMs are even more powerful in this area; in particular Testolone (RAD-140) and Ibutamoren (MK-677).

A misguided assumption with SARMs is that they won’t suppress testosterone but this is not always the case with Ostarine. Some other SARMs will have no suppressive effects, but potential users of Ostarine should weight this up as a factor when deciding which SARM to use as it can cause some suppression while some SARMs will cause none at all, and others can suppress more heavily than Ostarine does.

There is little real comparison between MK-2866 and SARMs generally with steroids. While all have anabolic effects, those of Ostarine are heavily targeted to bones and muscles it is non-steroidal. Steroids are of course synthetic hormones so work throughout the entire body; which is why we get the serious side effects which are not of anywhere near as big of a concern when using Ostarine and SARMs in general.

MK-2866 can deliver brilliant results but users should not try and compare these results with steroids as they are two very different types of compounds.

What Results Can I Expect Using MK-2866?

Because Ostarine is useful for both gaining muscle and retaining existing muscle, you can use it in bulking and cutting cycles. This is clearly going to deliver different results based on the way you use Ostarine in a cycle and what other compounds, if any, you stack it with.

When bulking you can expect to see superb gains that come without the bloat of fluid retention. Although the size of your gains won’t rival that which can be achieved with the most powerful bulking steroids, you also won’t have the crippling side effects that come with them. Working hard at your training program while using Ostarine will allow you to still get some very impressive gains, and they should be much easier to maintain after the cycle because your gains will be clean lean muscle without extra water weight.

If using Ostarine as a bridging compound between bulking cycles you can expect to see easier and better muscle preservation between your main cycles. This SARM actively works to stop catabolism (the loss of muscle) which is what it was originally designed to do. This makes it perfect for lean muscle maintenance with little to nothing in the way of side effects. For this reason it is one of the SARMs which can appeal to more hardcore steroid using bodybuilders.

Side Effects from MK-2866 (Ostarine) Cycle

When used at high doses that are likely by bodybuilders and athletes, we see one of those same problems that come with anabolic steroid use: suppression of natural testosterone production. High dosages and long cycles bring about this condition in males and is why following up with PCT, just as with steroids, is needed in these circumstances.

Very short term or low dosage use of Ostarine may not always come with this side effect. Ostarine won’t suppress testosterone totally like steroids do and the effect of this can vary between individuals. While SARMs do not aromatize there is some evidence that slight rises in estrogen can still occur, but for most people this won’t be enough to require the use of an anti-estrogen.

Ostarine, like all SARMs, is still in research phase by its developer and as such, there are still aspects that remain unknown about both its short term benefits and potential long term side effects. Over $35 million dollars has been put into research and trials of Ostarine so far.

Like all SARMs, Ostarine is prohibited by the WADA (World Anti-Doping Agency). There have been a number of high profile positive drug tests for this SARM among professional athletes over the past several years with many claiming to have unknowingly taken the ingredient when it was not labeled on supplements. Ostarine has a half life of 24 hours and can be taken once daily.

Most users of this SARM will experience little to no side effects. Some people might notice mild side effects. As Ostarine, like all SARMs is a relatively new substance, its full spectrum of possible side effects – especially at doses used for performance enhancement – are not yet fully discovered and much of the current knowledge comes from the personal experience of users themselves. This means there may be possible unknown side effects for individuals.

Estrogenic Side Effects

There is no aromatizing activity with Ostarine so you can expect no estrogenic related side effects that are common with steroids like breast tissue growth in males and water retention. It can come as some surprise though that despite the lack of aromatizing activity it is still possible for Ostarine to raise estrogen levels a small amount. This will be mild enough that you won’t need to use an anti-estrogen drug and in fact can have some benefits in males as men do require small amounts of estrogen – making use of an anti-estrogen drug in this case can eliminate all estrogen and bring about hormonal imbalances therefore it is not recommended nor is it required.

Androgenic Side Effects

Acne and hair loss and any other androgenic effects are not an issue when using Ostarine. This is because Ostarine, as a SARM, is very specific in the androgen receptors it binds to and it does not impact areas that bring about negative effects that are so common with steroids. Additionally, female Ostarine users are not at risk of developing masculine features like hair growth or deepening of the voice.

Liver Toxicity

No liver toxicity is associated with Ostarine and this is one of its biggest advantages over a lot of steroids that do pose a great risk to the liver. So you won’t need to worry about the extra cost of supplements to support the liver.

Cholesterol

Compared with anabolic steroids which are known to often cause very serious impacts on cholesterol, Ostarine’s effect on cholesterol is at worst only mild. In some people it might slightly reduce levels of good cholesterol but for the vast majority of people this is unlikely to be a concern or even noticeable.

Testosterone Suppression

Ostarine can potentially cause some level of testosterone suppression. This will vary between people depending on dosage and individual health factors, so some will need to do PCT and others will be able to come off Ostarine and maintain normal testosterone function.

Ostarine won’t suppress testosterone to the level that steroids do, which can often shut it down completely, but for some guys it can be enough to encourage the addition of an additional testosterone booster to the cycle, such as in the form of a supplement. New users to Ostarine can evaluate its impacts on testosterone by starting a low dose and adjusting as needed.

Common Q&A Related to MK-2866 (Ostarine)

What does Ostarine do to the body?

Ostarine has anabolic effects which target the muscle and bone where it promotes muscle growth and an increase in bone mineral content which results in stronger bones. Ostarine is excellent at helping retain muscle during dieting and cutting phases, but also helps the body put on bulk and increase strength.

Is Ostarine legal?

Ostarine has no approval for human use in any country and is prohibited by WADA by being listed as an S1 Anabolic Agent on their list of banned performance enhancing substances. This means if you are competing in any professional sporting competitions and you test positive for Ostarine, you could be banned from the sport forever. Buying Ostarine online is the only option as it is not available anywhere through official sources. It is not difficult to find but it must be kept in mind that the only legal avenue for obtaining Ostarine in the USA is for research purposes, so you are making use of a legal loophole when buying this or any other SARM.

Does Ostarine build muscle?

Yes, one of the core goals of Ostarine is for muscle growth as it was originally designed to treat people suffering from illnesses that cause muscle wasting. For bodybuilders and athletes who want to add to their existing muscle, using moderately high doses of Ostarine and combining this with intensive weights training can result in impressive muscle growth and while it won’t be as powerful as steroid, it’s possible to gain 8 pounds of muscle in an Ostarine cycle.

Does Ostarine really work?

Ostarine has shown in human studies to be effective at improving muscle mass and general fitness and physical ability. Many SARMs do not have any human trials to prove their effectiveness, however Ostarine has shown clear benefits in both human and animal studies. You can use Ostarine for any goal: bulking, cutting, improving muscle recovery, and body recomposition.

How safe is Ostarine?

Compared with steroids, Ostarine is considered much safer and certainly with a much lower risk of side effects. It does not come with the common side effects seen with most steroids like water retention, gyno, acne, hair loss or raised cholesterol.

Importantly, Ostarine is much safer for the liver than most anabolic steroids because it is not liver toxic. Despite these known facts, the possibility of unexpected short and long term effects can not be ruled out as more extensive studies have not been done on this relatively new compound, which is why users of any SARMs should always proceed with caution.

Can Ostarine cause gyno?

No you will not experience male breast tissue enlargement (gyno) with Ostarine as it does not aromatize – this means Ostarine doesn’t cause a conversion of testosterone to estrogen or to DHT which is the underlying cause of gynecomastia that real steroids cause. You can safely use Ostarine without the concern of gyno or water retention, so there’s also no need to add other drugs to your cycle, like the anti-estrogen drugs which are almost always needed when using steroids to combat gyno.

Is Ostarine a steroid?

Ostarine is not a steroid. It is a SARM (Selective Androgen Receptor Modulator). Steroids make use of hormones (usually testosterone or similar) that directly enter the body, while the SARM Ostarine is not a hormone and only targets very specific androgen receptors in the areas that are most important: the muscles and bones.

Is Ostarine a PED?

Ostarine is considered as a performance enhancing drug (PED) by World Anti-Doping Agency which makes it a prohibited substance in competitive sports. All SARMs are included on this list and some athletes have tested positive over the years.

My Conclusion and Recommendation

If you want a big boost to your anabolic state then MK-2866 is one of the best options available outside of anabolic steroids. You clearly will not get the rapid mass building that’s possible with steroids but with a slower and steadier approach, quality gains can be made with Ostarine and it’s also become a useful bridging compound between steroid cycles, so its use is not just limited to people who don’t use anabolic steroids.

If you decide to try Ostarine I recommend buying it here.

If you'd like more real, NO-BS information on using steroids be sure to check out Straight From the Underground (my recommended underground steroid guide). Everything in this book is a real-life experience, not theory.