Ostarine Cycle Length: How Long Can You Take MK 2866?

Androgen receptors are critical to the functioning of various organs, muscles and bones in our body. This makes them a hot cake when it comes to research about therapeutic drugs. They are to be used by binding selective androgen receptor modulators or SARMs to androgen receptors in the human body. And unlike anabolic steroids, these agents do not have a negative growth impact on primary or secondary sexual organs. 

Ostarine is made to work like testosterone and promote or maintain libido, fertility, growth of the prostate and muscles. It also helps build muscle, burn fat and stop muscle wasting in those with serious illnesses like advanced cancers, end-stage renal diseases or osteoporosis. This is quite common in the world of research.

Now, ostarine is not approved for human consumption in the US and in several other countries. It also features in the S1 Anabolic Agent category of the World Anti-Doping Agency (WADA) Prohibited List. It is also available under the name Enobosarm or MK-2866 or GTx-024. 

So if you’re going to use it, you need to know how long you can cycle it for. This post will mainly focus on the optimal Ostarine cycle length. If you are looking to browse through some of the available SARMs out there, you can find them here.

How much Ostarine to take and how long to take it?


Here’s the thing. For best results, you must keep your ostarine dosage between 10-25 mg per day. However, there is no concrete research as to the benefits of taking 25 mg per day for a longer period of time. 

If you are a beginner, you should start with no more than 10-15 mg per day for no longer than eight weeks. Since this is an unregulated drug with unknown side effects on the human body, you must monitor the growth of muscle and loss of fat in your body on a daily basis.

And about diet. When you are on SARMs, be sure to increase the amount of protein you consume.

Example of an Ostarine cycle for men

Example Cycle

First things first. Remember to procure pure products from a good source. Keep the ostarine cycle limited to eight weeks. If you are an experienced user, you can extend it to 12 weeks. Keep the dosage limited to under 20 mg a day, 15 mg a day if you are a beginner. But if you want to see what a typical ostarine cycle looks like, here it is.

  • Weeks 1-4: 15 mg per day
  • Weeks 5-8: 25mg per day
  • Weeks 9-12: Start post cycle therapy (read the Ostarine PCT Guide)
  • Weeks 12-16: A break from SARMs

Ostarine is typically taken in eight individual cutting and bulking cycles. The dosage is greater in the bulking cycles and you will find yourself gaining muscle mass during this period.

A little surplus of calories is also a good thing in the bulking cycle. And always remember that SARMs work best when combined with training and nutrition.

Week 1-4Week 5-8Week 9-12Week 13-16
Ostarine Dosage:15mg/day25mg/dayNoneNone
Nolvadex Dosage:NoneNone20mg/dayNone

Example of an Ostarine cycle for women

Ostarine for Women

When it comes to women and SARMs, there are a few tweaks to make to the cycle. It’s not a question of equality but about biological differences. For women, a cycle usually lasts from four to eight weeks. This is dependent on the amount of experience your body has with SARMs.

If you are a beginner, keep it limited to four weeks (as opposed to eight weeks for men). If you have done this before, you might still want to keep this at six weeks. If you are a professional consumer, that’s when you take it up a notch and do it for eight weeks. But the dosage should ideally stay at 10 mg per day. Never more than that.

And also, you must also keep a track of the way your body is responding to the SARMs. Be particularly mindful of what is happening in the last two weeks. That is when any possible side effects start to show.

  • Weeks 1-4: 10 mg per day
  • Weeks 5-8: 15mg per day
  • Weeks 9-12: Take a break from all SARMs (PCT not needed for women)
Week 1-4Week 5-8Week 9-12Week 13-16
Ostarine Dosage:10mg/day15mg/dayNoneNone

Women typically experience weight loss, especially with ostarine, because it is good during cutting cycles. You will, however, have trouble gaining muscle mass. That happens after a few cycles.

If you want to stack ostarine with another SARM, consider andarine and cardarine. They are both good for weight loss and cutting fat. The recommended dosage is about half of what men take. So, if they take 20 mg, you must stop at 10 mg. If you get greedy with ostarine, here are the possible side effects.

  • Acne all over the body
  • Menstrual trouble
  • Increase sex drive
  • Muscle pain and/or swelling
  • Ligament troubles

Post-Cycle Therapy: Do You Really Need It?

PCT (Post Cycle Therapy)

The idea behind post-cycle therapy or PCT is to give your body a resting time of four or more weeks between cycles so that it can reach equilibrium and get ready for the next cycle if there is one lined up. You can make it longer if you feel like your body needs it. This is not an area where you ignore what your body is telling you.

While you don’t have to do post-cycle therapy after an ostarine cycle, it is advisable to do so. It is one of the mildest SARMs out there. Typically, medications like Clomid or Nolvadex are used in PCT cycles to ease any lingering effects of a powerful SARM. But Clomid has shown to induce depression in some users. 

Also, you can’t get them over the counter so forget that. What you want to do is get a stacked supplement with quality ingredients like Rebirth and it will be enough. If you want to learn more, check out our Ostarine PCT Guide.

Final verdict for Ostarine cycle length and dosages


Ostarine or any other SARM has to follow a particular cycle that matches the goal of taking the supplement. The length of the cycle is very important. 

In this case, you need to start with eight weeks of intake. Then go for four or more weeks of post-cycle therapy. It is not mandatory but will be good for your body. After that, take a break from all types of SARMs for 3-4 weeks so that your body comes back to normalcy.

You must also remember to source high-quality ostarine. There are too many fakes and since the side effects of this product on human beings are not known, it is too big a risk. Make sure you also get the proper amount of exercise and eat well during these eight weeks. If you are experienced, you can push it to 12 weeks but no longer than that.

Chris Jackson
Chris Jackson

Chris Jackson, co-founder of Sarms.io, is a renowned fitness blogger, physique model, and evolutionary bioscience researcher specializing in SARMs (Selective Androgen Receptor Modulators). His extensive work, characterized by cutting-edge research and practical training advice, has made Sarms.io a leading source for accurate, credible information on performance enhancers. With a dedication to improving the understanding and application of SARMs in optimizing human performance, his contributions have not only expanded public awareness but also shaped the conversation around these substances. Chris's pursuit of knowledge and commitment to sharing it continue to inspire many in their fitness journeys.

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