Understanding the Essential Basics of Testosterone and Beyond

Basics of Testosterone

Get the truth about anabolic functions of the human body

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Of all the hormones at work in the human body, none has received more press from the widest array of interested parties than testosterone. Not only has it been the focus of scientific journals with its effect on health, but it has also become central to any discussion regarding muscle growth, aging and the endocrine system. It has even been libeled in feminist political tracts denouncing it as a "poison" which must be neutralized.

The truth is, testosterone plays an important role in all these areas. And with the exception of gender politics where hostility is touted as science, the interest it engenders is justified.

The bottom line is that testosterone is important for the health and well-being of both sexes, and its absence or decline is cause for concern. It is a sign of the times (aided by a relentless and fatuously PC media) that leads to a society where even a hormone can be politicized.

Although the female comes first to mind when we think of human cycles (e.g. ovulation), research in the biological sciences proves that men are not immune to the changing tides of nature. Men have cycles too, though not as dramatic. This fact is evident from the very first look at how testosterone functions in the male body, starting with blood level which tends to be higher in the morning and lower in the evening. However, any attempt at drawing a simple hormonal scenario would be misleading. Many factors (as well as other hormones) are involved in all aspects of human behavior. This is why despite lower nocturnal testosterone levels, most men are more romantically inclined in the evening than at breakfast time. And indeed as we look further we will discover a wide array of hormones involved in human sexuality for both genders.

Testosterone peaks in puberty and declines with age. It is produced in the testicles in men and in smaller amounts in the adrenal glands of both sexes. Women also produce some in their ovaries.

But it is in the testicles of the male, in the Leydig cells, where the lion's share is manufactured. In these specialized cells the cholesterol is converted to pregnenolone and that in turn is converted into testosterone. Testosterone produces the obvious male characteristics first apparent at the onset of puberty such as a deepening of the voice, beard growth, lean muscle tissue and sperm.

In both men and women testosterone works as an anti-depressant and boosts self-confidence. The sex drive of both genders involves a whole host of hormones and peptides in addition to testosterone such as DHEA, vasopressin, serotonin, dopamine, LHRH, PEA (phenylethylamine) and Oxytocin. All of these substances are in continual flux relative to one another like so many levels on a stereo equalizer as nature mixes and remixes the hormonal sexual music we dance to. To add to the complexity, our hormones, while affecting our behavior, are in turn affected by how we behave through all the phases of interpersonal contact - from first noticing someone and seeking eye contact, responding to verbal and nonverbal signals, right through to the pursuit, courtship and finally physical relations and emotional attachment.

Testosterone comes in two forms: bound and free. The amount of testosterone freely circulating in the blood is the vital number which determines the effectiveness of the hormone. Bound testosterone is free testosterone which has become trapped by a protein molecule such as albumin or globulin. Doctors have for a long time measured only the total testosterone level, which is not a very useful evaluation. The free form - i.e. the active stuff - may represent only 5 percent of the total figure, but that 5 percent can be explosive.

Testosterone is secreted in pulses by the body. A doctor cannot easily, whether by injection or oral supplementation, mimic nature's delivery system. Injections, not surprisingly, can produce unusual highs and lows. This pulsing release pattern explains the importance of having your testosterone levels checked not once but three times at 15- or 20-minute intervals and the results averaged. Both free and bound forms should be measured to produce a more accurate result. The morning is a good time since more of the hormone is likely to be circulating.

Paradoxically, although testosterone is associated with the sex drive and the hunt for a partner, it is also the "loner hormone." It drives a man to his sexual conquest but then it will also cause him to be emotionally separate from his partner afterward. All those other hormones are in the mix to balance out some of the negative effects of each individual hormone.

If testosterone predominates too much, the hormones which drive a man to seek a connection and attachment will be overwhelmed, and we end up with the surly bad-boy biker type -tattooed and cruising for some action but not interested in any deep conversation or long-term commitment. This could very well be nature's idea of spreading the seed as far, fast and wide as possible by moving on after each encounter. In popular culture such a figure is epitomized by James Bond or Clint Eastwood's The Man With No Name persona (probably better to escape child-support payments). Oddly enough, there is also evidence that testosterone contributes to making a man sensible and logical (another paradox!) Achieving success in life and vanquishing enemies enhances testosterone level while losing suppresses it.


Testosterone-replacement therapy may be an option for some men (and women) with low levels. However, there is nothing to be gained by adding more testosterone if levels are normal. In such a case the body will simply shut down its own production.

One of the major paradoxes which bedevil athletes who take steroids (testosterone is a steroid hormone) is that the body may very well convert the excess to estrogen, its veritable opposite number, defeating the whole point of therapy - all the more reason to stay within the bounds of what is considered a normal hormonal level for you. If your level is significantly below what your doctor considers to be normal and healthy for you, by all means look at the options. Bringing a low testosterone level back to normal improves cognition (thinking ability), works as an antidepressant, and increases lean muscle tissue. It augments sex drives and, though it can promote aggressive tendencies, it also contributes to assertiveness and self-confidence. A fine line exists there. Not surprisingly, career women have been found to have higher than normal levels. When you are tested, however, be sure to evaluate the level of free testosterone. That is the metabolically active kind.


As men get older, they experience a decline of just about everything else the body's organs and glands produce. Should you and your doctor decide that testosterone-replacement therapy is the way to go, you will have to consider various delivery systems: injection, oral (swallowing a pill), sublingual (a lozenge under the tongue), implantation of a hormone-releasing pellet, or a transdermal patch worn on your skin.


This is the most common way to go. Every three weeks or so the doctor injects about 250mg. Injection is the most effective method of getting the stuff into your blood without losing any in the intestinal tract or having it screened out by the liver. It packs a powerful punch and can triple your blood level, but since it will also cause your body to shut down its own production, you won't want to consider this option unless your testosterone is extremely low. Obviously, if you take it when your body doesn't have a testosterone problem, you will have a testosterone problem.


Absorption will result in a lower level than what can be achieved via injection. Possible side effects include liver damage, raised cholesterol, salt retention, weight gain, enlarged breasts (not to be confused with pecs!) due to the excess converting to estrogen, acne, water retention, high blood pressure and prostate enlargement. Only a small percentage of people experience side effects but the possibility is worth considering.


Similar to injections, this method bypasses the digestive process and the liver. The blood level is more predictable than with popping testosterone pills but naturally it is lower than what can be achieved via injection.

Transdermal Patch

Sounds perfect and easy until you find out it's not worn on the shoulder but on the scrotum. This method more closely imitates the rise and fall that are features of normal testosterone pulse production by the body. There is also less excess produced thereby avoiding the problem of estrogen conversion. However (there is always a however in biomedicine), applying testosterone directly to the testicles could raise the risk of prostate complications - benign or otherwise. Be advised. The long-term effects of high doses to that... uh ... area are unknown.

Since we've mentioned the prostate we might as well quickly run down the basic check for its health. Check your free and total testosterone levels. Have a PSA (prostatic specific antigen) test. Have a prostatic ultra- sound (detects tumors). Have a prostatic rectal exam. (This is one exam you won't have to study for!) How effective? The ultrasound test should pick up about 60 to 70 percent of cancer growths greater than 5 mm. The PSA blood test should detect about 70 percent of prostatic cancers. The rectal exam is regarded as necessary and in conjunction with the other two tests is the best available detection method today.

Testosterone like all human hormones is extremely important to the health and well-being of both men and women. While not obsessing over it, you want to keep tabs on your levels as time goes by. And remember - a hormone is not a vitamin. Resist the urge to increase your testosterone level beyond what is normal and healthy because if you do, you may find your prostate growing faster than your biceps. Also be sure to schedule sufficient rest between workouts to avoid suppressing your immune system and hormone levels. An overworked endocrine system is one of the reasons overtraining leads to stagnation and forced layoffs. The challenge of training is not to see how much or how long you can train or how much punishment your body can take, but how much you can improve your physical condition and your health. Good luck!

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