S4 (Andarine) or Acetamidoxolutamide, is a SARM (Selective Androgen Receptor Modulator). But the idea for S-4 didn’t start out as many believe.
It wasn’t an attempt to create a safer version of steroids or any of that nonsense people use to sell anabolics.
S-4 started out as a new development for male contraceptives and showed promising results like decreases in spermatogenesis and huge boosts in male libido. For any of you who have had trouble getting your wife pregnant while on sarms…you’re welcome.
However, when researchers began experimenting on mice with S4, they discovered interesting findings about how this first generation SARM affected castrated lab mice.
Not only did Andarine increase the production of muscle mass and calcium for bone density, but was COMPLETELY SELECTIVE in its tissue growth!
As studies continued, many of these research trials resulted in astonishing outcomes creating a benchmark for even more research.
How S4 Works
To start, let’s describe what a SARM does.
There are three type of chemicals that act on the androgen receptor (AR):
1st is the an AR antagonist, which is a chemical that binds to the receptor to prevent it from activating.
2nd is an AR agonist, which binds to the receptor and detaches, then binds again, over and over.
3rd is an AR modulator, or basically a molecule that attaches to an AR and changes its structure to react however it wants.
A SARM such as S-4 is a good example. S-4 attaches to the AR and sticks to it; each time the AR interacts with testosterone, S-4 forces it to produce genes that exclusively benefit muscle and bone growth. In other words, S4 is a form of SARM that attaches to the androgen receptor (AR) the same with regular androgens, the only variation is that S4 generates selective anabolic activity.
As mentioned earlier, SARMS function by tying to the AR resulting to anabolic activity. Due to this fastening and stimulation, more protein is produced which allows muscle building. S4 can trigger muscle development in the same way as steroids, but minus the same unwanted side effects.
S4 is a SARM with utmost androgenic effects and is 33% of the strength of testosterone when attaching to AR.
S-4 also increases the amount of muscle mass produced by desensitizing the AR to the individual’s natural testosterone to influence a stronger effect.
The Key Benefits of S4 (Andarine)
S-4 is by far the most versatile SARM ever created. Not only is it the first SARM approved for a stage 2 research study, it has become the most analyzed and investigated SARM so far. After the discovery of its anabolic potential, the primary purpose of S-4 aimed to develop an alternative treatment to age-related muscle wasting, osteoporosis, and similar symptoms of hypogonadism, or end-stage renal disease.
Aside from preserving lean body mass, S4 can also help improve it.
From a stage 1 study, S-4 has provided evidence of a 3.3 lbs increase in less than 90 days with no increases exercise or change in daily diet. An unintended side effect (or benefit if you will) is the decrease in body fat [Chen et al., 2005; Gao et al., 2005; Kearbey et al., 2007]. Decreases in body fat are dependent on the person’s genetics, but it will definitely have strong effects on the body’s ability to oxidize fatty tissue. S-4 was found to not only have a great affinity (potency in binding to androgen receptors), while also presenting greater anabolic effects than some traditional steroids [Kearbey et al., 2007].
Aside from its muscle building advantages, S4 won’t cause liver damage, can prevent gynecomastia (enlarged breasts in men) and can help boost your overall health.
Here are some of the other benefits of Andarine that are worth noting:
Very minimal growth on secondary sexual organs such as the prostate.
The LDL/ HDL ratio is not affected which makes it a low cardiovascular risk.
0% chance of aromatization, male breast lactation, or rise in any other female characteristic during the post cycle recovery. [Kearbey et al., 2007]
Testosterone is not diminished in any capacity during the post cycle recovery.
Very exclusive in tissue selection and growth which means it will not cause heart enlargement or damage to neighboring organs.
SARMs do NOT require the utilization or devouring of liver enzymes to activate their anabolic effects. This eliminates any risk of hepatotoxicity or hepatitis.
Although SARMs such as S-4 are not as powerful as comparable steroids such as Winstrol, they do not require the extensive post cycle therapy and can be cycled back to back throughout the year. Over the course of a year, obtaining the same results is very possible.
SARMs is very female friendly and does not cause excessive masculine features such enlarged sexual characteristics.
S-4 has overall presented larger increases in muscle mass than DHT.
Full Muscle Regeneration & Lean Body Mass
Once more, an early study done on S-4 provided proof of full muscle regeneration in volunteers with degenerative disorders without the use of exercise and the minimum dosage of 3mg/kg/day. Changes can be seen anywhere from 1-2 weeks. This was the very first study classified S-4 as CLINICALLY SIGNIFICANT by improving skeletal muscle strength, lean body mass, and a reduction in body fat [Chen et al., 2005; Gao et al., 2005; Kearbey et al., 2007]. Unfortunately, there are always some side effects that arise when using Because S-4 is a ligand by definition, the side effects will never be permanent even at supraphysiological dosages and can be easily avoided through proper dosing.