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So you want to try Ostarine (MK2866)... HERE ARE THE FACTS OF THIS WONDERFUL SARM!!


What is Ostarine?

Ostarine is the SARM that GTx is developing for the prevention and treatment of muscle wasting. It is currently undergoing clinical trials and may eventually be the medical prescription for prevention of cachexia, atrophy, and sarcopenia and for Hormone or Testoserone Replacement Therapy.

As a research chemical, Ostarine belongs to a class of chemicals known as SARMs or selective androgen receptor modulators. SARMs create selective anabolic activity at certain androgen receptors and not others, hence their name. Compared to testosterone and other anabolic steroids and pro hormones, the advantage of SARMs such as (Ostarine) MK-2688 is that they do not have androgenic activity in non-skeletal-muscle tissues.
Ostarine is effective in not only maintaining lean body mass (LBM) but actually increasing it.

It is often described or named S1 on various interenet sources, however this is actually incorrect as S1 was a SARM that was develped quite early and is no longer undergoing any further development.

How does it work?

Selective androgen receptor modulators (SARMs) bind to the androgen receptor and demonstrate osteo (bone) and myo (muscular) anabolic activity.
Androgen receptor activation

Binding and activation of the Androgen receptor alters the expression of genes and increases protein synthesis, hence builds muscle.​
So in essence, SARMs such as Ostarine causes muscle growth in the same manner as steroids, however unlike testosterone and other anabolic steroids and prohormones, SARMs (as nonsteroidal agents) don’t produce the growth effect on prostate and other secondary sexual organs.

Ostarine in particular exerts its anabolic effects on muscle tissue almost exclusively. So not only does it represent a new potential treatment option for a wide spectrum of conditions from muscle wasting diseases (from age-related to AIDS or cancer-related), but is also has immense potential for muscle building for Bodybuilders, fitness, athletes and an agent to minimize atrophy during recovery periods from serious surgery or similar situations.

Evidence of Ostarine’s Abilities?

To date, GTx has evaluated Ostarine in eight clinical trials involving approximately 600 subjects including three efficacy studies. A four month Phase IIb clinical trial enrolled 159 patients with the study meeting its primary objective of an absolute increase in total lean body mass (muscle) compared to placebo and the secondary objective of muscle function (increase in strength).

In particular application to bodybuilding, there have been many logs of users on various forums using Ostarine as an aid to increase lean body mass and strength levels.

Uses of Ostarine

Lean muscle gains (bulking)

As Ostarine is the most anabolic of the available SARMs, its first and formost use must be when trying to gain lean muscle.
Now the gains in absolute weight won’t be comparable to steroids such as diannabol, however what will be gained will almost exclusivley be lean mass. Due to the lack of shutdown in comparison to steroids/prohormones, a PCT period is not needed and almost all the mass that is gained on Ostarine is kept once the cycle is finished.
Doses of 25mg for 4-6 weeks are the most common protocol for such goals. Over this 4-6 week period will typically produce 6lbs or 3kg of lean, keepable gains. However the abundant side effects of steroids/prohormones will not be present.

Users have as high as 36mg [only recommended for those who weigh in at 210lbs (95kg)+] for periods as long as 8 weeks. However the potential for suppression from such doses is higher and users would have to look into a PCT protocol after undergoing such a cycle.
As the majority of Ostarine supplies come in 30ml bottles at 25mg/ml, a dose of 17.5mg per day will give the user a 6 week cycle from one bottle, a very good compromise between an anabolic dose and cost.

Losing Bodyfat (cutting)

Ostarine would primarily fit into a cutting protocol for the maintainance of muscle mass whilst reducing calories.
One of the most disheartening outcomes of cutting is the loss hard earned muscle mass.
The drop in metabolic rate and hormone levels (T3, IGF, Testosterone etc) with the lack of calories is a perfect catabolic enviroment for loss of muscle tissue.
As Ostarine has anabolic effects, the dieter can cut calories without having to worry about muscle or strength loss.
Ostarine has also shown noticeable nutrient partioining effects among users, another reason why it can be of great help when cutting.

A 12.5-15mg dosing protocol for 4-6 weeks is good for cutting with Ostarine without undergoing any side effects or suppression.
However it must be stated that due to the lack of androgenicity, muscle hardness and overall results are not as prominenant as with the SARM S-4.

Recomping (gaining muscle and losing bodyfat at the same time)

Recomping is where Ostarine really shines.
The recomping effect of losing fat and gaining muscle at the same time is what the majority of users are looking for. Trying to achieve this when you are not absolutely new to training is extremely difficult.
Where Ostarine shines for recomping is in its nutrient partioning benefits. Calories are taken from fat stores and calorie intake is fed to the muscle tissue. In fact many users report that Ostarine consumed at maintainace calories produces weight loss, whilst still getting increases in strength and muscle mass!

One of the most important factors of recomping is TIME. As you are trying to achieve multiple objectives, it requires a longer time period to notice good recomp effects so even when running steroids, these would have to be longer run injectible compounds as oppose to the short used liver toxic oral steroids/prohormones.

Although Ostarine is taken orally, as it is not methylated it is not as liver toxic as other oral steroids/prohormones. Therefore it can be run for longer than the standard 4 week period with the aforementioned compounds.

The dosing protocol of 12.5-25mg for 4-8 weeks will give excellent recomp effects.
Diet must also be optimized to where calories are just above maintaninance with at least 30% coming from lean sources of protein to get the best recomp effect.

Injury Prevention

As mentioned by Furuya, the effects of MK-2688 translate to anabolism in bone as well as skeletal muscle tissue, which means it could be used in the future for a wide variety of uses such as osteoporosis and as a concurrent treatment with drugs that reduce bone density.
Therefore it has great application as a compound to use for rehabilitation of injuries, in particular bone and tendon related injuries.

Doses of 12.5mg per day is recommend for such purposes and improvement in joint movement that can be seen after just 6-8 days.
Timing of Doses

As Ostarine has a half life of around 24 hours, each of these doeses only has to be taken orally once a day, therefore its also offers an extremely convientinet supplementation intake.
Ostarine and estrogen concern

SARMs cannot be aromatized, conferring all their effects to AR binding and not to metabolic conversion to active androgens/estrogens.
However blood work from users has shown a slight elevation in serum estradiol levels (which may be one of the factors in its high effectiveness for treating tendon, ligament, and bone injuries or illnesses.
This elevation is extremely small and is no case for concern. If however you are absolutely concerned about slight increases in Estrogen, you can always opt for low doses of OTC AI’s such as 6bromo or very very low doses of prescription AI’s like adex or aromasin.

Advantages Of Ostarine when compared to Steroids/Prohormones

  • There is no need for pre cycle supports such as Hawthorn berry.

  • There is no need for on cycle supports such as milk thistle for the liver, policosanol or RYR for cholesterol etc.

  • Some suppression may be present at doses of 25mg+ run for longer than 4 weeks, however a stringent PCT of prescription SERMs like Nolva or Clomid is not necessary.

  • High oral biovailabilty without significant damage to your liver as with oral steroids/prohormones.

  • Great sense of well being while on, (without the aggression which can often detrimentally impact users daily lifes).

  • No need for a long time period off between cycles; the recommended time of period for normal cycles would be Time on +PCT, so for a typical 6 week cycle and 4 week PCT, a user would have to wait another 10 weeks after PCT to start another cycle.

  • Ostarine (MK-2866) also resulted in a dose-dependent decrease in LDL and HDL cholesterol levels, with the average LDL/HDL ratio for all doses remaining in the low cardiovascular risk category – hence there is little impact on cholesterol values.

Advantages Of Ostarine when compared to other SARMs

  • The metabolite M1 wich seems to cause toxicity in S4 (temporary occular disturbances) is not present in Ostarine.

  • Also unlike S4, Ostarine does not have androgenic properties in non muscle tissue.

Ostarine Summary

  • Anabolic even at doses as low as 3mg

  • Great for strength

  • Great for lean mass gains

  • Great for body recomposition

  • Great for endurance (aerobic or anaerobic)

  • Joint healing abilities

  • Half life of circa 24 hours – only once a day dosing required
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Re: So you want to try Ostarine (MK2866)... HERE ARE THE FACTS OF THIS WONDERFUL SARM

i was thinking of adding it on a PCT after a var (or tbol) + proviron cycle. so happy to see that offer.
Re: So you want to try Ostarine (MK2866)... HERE ARE THE FACTS OF THIS WONDERFUL SARM

I love osta!...what a great read, it reminded me how awesome it is!
Re: So you want to try Ostarine (MK2866)... HERE ARE THE FACTS OF THIS WONDERFUL SARM

my rat is gonna run this as a bridge. 25mg a day.

what a weapon to hold onto gains between cycles and have very little suppression

absolutely bro... running hcgenerate or test infusion with it ensures little to no suppression...
Re: So you want to try Ostarine (MK2866)... HERE ARE THE FACTS OF THIS WONDERFUL SARM

i was thinking of adding it on a PCT after a var (or tbol) + proviron cycle. so happy to see that offer.

i never run a pct without it...
Re: So you want to try Ostarine (MK2866)... HERE ARE THE FACTS OF THIS WONDERFUL SARM

then its settled, my rat is running test infusion and Ostarine after next cycle as a bridge with some hcgenerate thrown in here and there .


that will be a nice run... if your rat really wants a bad ass bridge then you should give him some s4 and gw...
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