Testosterone

Testosterone is a sex hormone produced under the influence of Adrenocorticotropic Hormone (ACTH). Testosterone is linked to high levels of curiosity and aggression. Sex hormones are manufactured from cholesterol which is converted to Pregnenolone by the ACTH. High levels of ACTH therefore stimulate greater manufacture of testosterone from cholesterol. Testosterone is indeed produced in large quantities in the testes, and androgens (the parent hormones that give rise to testosterone) are actually produced by two small glands next to the kidneys, the adrenals, in both men and women. That's right, women also do produce this sex hormone, just as men produce estrogen, it is just that testosterone is produced in higher quantities in the male and is so typically classed as a male sex hormone. Below you will see a diagram of exactly how the production of testosterone is brought about in the body.


Primarily in the male, testosterone is manufactured by the Leydig cells in the testes at varying amounts throughout a persons life span. Testosterone is an anabolic hormone that will increase protein synthesis in both men and women, however adult males produce significantly more than females. The adult male body manufactures between 2.5 - 11 mg per day, while females only produce 0.25 mg. Typically the effects of testosterone on the human body are made greatly evident during the time of puberty. What happens at this time is a sudden increased surge in testosterone output and this gives rise to dramatic physiological changes to the male. These sudden changes to characteristics include a deeper voice, body and facial hair growth, increased oil output by the sebaceous glands, development of the sex organs, maturation of sperm and an increased libido. You must understand that the male reproductive system does not function properly if testosterone levels are not significantly high enough. It is these properties that are catergorized and grouped as androgenous androgenic masculinizing effects.

The increase and stimulation of the primary androgenic hormone testosterone will also cause an increase in the growth of cells - this is the anabolic properties of the hormone. Anabolism means the phase of metabolism in which simple substances are synthesized into the complex materials of living tissue. This will include the enhanced rate of protein synthesis which leads to the accumulation of new muscle tissue, as well as an increased rate of calcium retention in bones. You will also find that this primary male sex hormone also increases the transportation of oxygen around the body due to the increased production of red blood cells, called erythropoieses. These are all of the reasons why the typical male of the species has a greater amount of muscle mass and a higher red blood cell count. Females, as stated above, only produce a small fraction of this hormone that the male produces. You will find that women have a much higher estrogen to testosterone/androgen hormone ratio and this equates to a greater level of body fat storage, lower accumulation of skeletal muscle tissue, a typically shorter stature and generally more apt to osteoperosis (weakening of the bones) in later life.

Stimulating testosterone production naturally, in order to promote muscle growth, is not an easy task, as a series of chemical changes are undergone within the body - beginning with the conversion of cholesterol into pregnenolone under the influence of ACTH. Let's take each stage in order.