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10mg - 60 capsules


Chemically, like all other SARMs, Ostarine does not possess any semblance to the traditional structure of anabolic steroids. The chemical structure of Ostarine has not been completely publicly disclosed by GTX, Inc. Although the company has not actually disclosed Ostarine’s chemical structure, the chemical composition can be found in databases of patents (in WIPO, for example), and has also been discussed in literature of various primary study sources.

It is important to note that Ostarine is actually frequently mistakenly linked to the chemical structure of Andarine (also known as S-4). Specifically, Ostarine is known as an aryl propionamide. It differs from Andarine via the replacement of the nitro and acetamido moieties on the phenyl rings, and they are replaced with cyano substitutions.

Like others in the SARM family, Ostarine binds with and activates the androgen receptors in the human body selectively, in such a way as to promote effects such as muscle gain, anti-catabolism, and strength-gains. It does this whilst avoiding androgen receptors in other areas of the body, such as the prostate, scalp, skin, etc. that tend to exhibit negative side effects.

This has brought much attraction by the athletic and bodybuilding community to Ostarine, so much so that in fact the World Anti-Doping Agency in January of 2008 had developed blood tests to detect it.

Ostarine is purportedly the most anabolic of all of the SARMs currently available.

Dosing and Administration of Ostarine

Most users, for the purpose of performance and physique enhancement, tend to utilize an Ostarine dosage of 12.5 – 50mg per day, with 50mg being the upper limits, of course. In one 3-month long study using 120 non-weight training, elderly individuals, it was revealed that Ostarine led to a dose dependent increase in lean body mass, with the largest dose group (3 mg/day) averaging an increase in lean mass of 3.1 lbs. Other anecdotal reports from bodybuilders and athletes using this compound often remark that 25mg per day seems to be the perfect and most common dosage. Venturing higher in the zone of 30+mg per day is usually only recommended for those who are weighing in at around 210lbs or heavier, and will start to exhibit HPTA suppression in the user.

For the purpose of injury, bone, and joint healing, individuals can experience satisfactory results with the minimum dosage of 12.5 – 15mg per day.

Being that Ostarine is near-perfect for female users, females can do well within the range of 6 – 12.5mg per day.

Ostarine is administered orally, and exhibits a half-life of approximately 24 hours, and therefore can easily be administered one to two times per day. It is up to the individual as to whether he or she wishes to administer half of their daily dosage in the morning, followed by the other half in the evening.

Ostarine Side Effects

Studies have demonstrated that Ostarine, if utilized in higher than recommended dosages, can suppress endogenous natural Testosterone production in the male human body. The same side effect can occur if Ostarine is utilized for longer than a period of 5 weeks. Therefore, it is indeed suppressive to the HPTA (Hypothalamic Pituitary Testicular Axis), and some sort of a post-cycle therapy (PCT) protocol is warranted.

Because Ostarine is not an anabolic steroid by nature, it carries none of the classical side effects of anabolic steroids, other than what has already been mentioned in this section. Ostarine does not exhibit any known estrogenic, androgenic, hepatotoxic, or cardiovascular side effects.

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