Aside from the difference in ester length, all of the versions of testosterone will have the same properties.

Testosterone is the most potent, naturally occurring androgen that is formed in the human body. It is responsible for characteristics specific to males and their sexual traits. This hormone is primarily secreted in the male gonads (testes), yet a very small amount is also secreted by the adrenal glands. The key roles of this hormone include: promoting health and well-being through enhanced libido, energy, immunity, increased fat loss, gaining and maintaining lean muscle mass, preventing Osteoporosis (loss of bone density) and possible protection against heart disease.

Every steroid begins as a form of testosterone. A slight adjustment is made to the structure of the testosterone molecule resulting in a slight alteration of the chemical properties of the hormone. Therefore, every available anabolic steroid known today is a derivative of its original "father," Testosterone. Testosterone's 100/100 (anabolic/androgenic) score is the template used to find the anabolic/androgenic ratio of all steroids. This hormone is the best-known potential mass builder, yet must be used with caution due its high risk of side effects because it can be converted with in the human body to a more androgenic form of itself, Dihydrotestosterone (DHT). DHT can in-turn form estrogen (the female sex hormone). Due to its mass building properties it is recommended as the base of any anabolic steroid cycle.

When testosterone is present, the muscle develops the ability to retain more nitrogen. Due to this increased nitrogen retention, more protein can be stored in the muscle, ultimately increasing its size. Not only does the size of the muscle change, the shape, appearance and number of muscle fibers may also be altered. Testosterone binds to the Androgen Receptors (A.R.) which thus causes accelerated muscle gain, fat loss, muscle repair and growth, because these are mechanisms stimulated by activation of the Androgen Receptors (either directly or as DHT).

Testosterone and its androgenic derivates can protect your hard earned muscle from catabolism (muscle wasting) when fat loss is desired and caloric intake is restricted. Because of its anti-estrogenic effect an ideal fat loss environment is created in the presence of Testosterone. Since the body is building muscle at an accelerated rate, more ingested food is shuttled directly to the muscle tissue (this is known as nutrient portioning) and away from fat. This is another indirect effect of testosterone on fat loss. Testosterone also promotes glycogen synthesis, which is activated by insulin in response to high glucose levels. Glycogen provides fuel to the muscle; therefore endurance and strength are increased while undergoing severe muscle breakdown during intense training and workouts.

Testosterone can have anabolic as well as virilizing effects. Anabolic effects include: growth of muscle tissue, increased strength, and increased bone density and maturity. Virilizing effects include: male secondary sex characteristics as discussed previously. Some of these effects include: maturation of the sex organs, deepening of the voice, and growth of facial and chest hair. The severity of these effects depends mostly on the levels and duration of circulating free testosterone. Testosterones´ anabolic/androgenic effects are dependant upon dosage, the higher the dose the higher the muscle building effect. Testosterone promotes aggressive and dominant behavior. It can also be converted to estradiol, which activates certain estrogen receptors. Caution should be taken when using higher dosages because of the increased risk of negative side effects

Testosterone, regardless of the ester, is highly versatile and should be considered the base of any (male users) cycle.
 

TESTOSTERONE SUSPENSION

Testosterone Suspension is a no ester injectable testosterone suspended in a water base. It is the simplest form of Test and gives you the most "bang for your buck," literally. It tends to be the most painful version to inject.

Testosterone Suspension enters and clears your body very rapidly. Athletes in drug tested sports organizations also use it for this reason. Many also use testosterone suspension immediately prior to a workout or competition, to increase aggression.

The availability of this compound is quite high, although demand is relatively low.
 

TRANSDERMAL TESTOSTERONE

Transdermal testosterone mimics the body's natural rhythmic release of testosterone through a time-release patch. Medically, this form of testosterone is used to improve testosterone deficiencies such as hypogondadism and sexual dysfunction with limited side effects.

Transdermal Testosterone is a fairly newer version of the hormone, sold in patch form. Two forms of transdermal testosterone are available; 1 has to be applied to the scrotum while the other is applied to other areas such as the thigh or back. Brand names: Androderm, AndroGel, Delatestryl, Depo-Testosterone, Depo-Testadiol (combination of Cypionate and Estradiol Cypionate), Testim, Testoderm, Testoderm TTS, Testopel Pellets, Virilon IM. Transdermal testosterone is not currently available in Australia, Canada, Denmark, France and The Netherlands.
 

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