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Testosterone: Support, don’t Suppress |
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Written by By Dan Gwartney, MD
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Tuesday, 03 February 2009 |
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Page 2 of 8
Of course, testosterone levels can be increased. The most common and reliable method used, particularly by athletes, is anabolic steroid therapy. Technically, only those steroids composed of testosterone esters actually increase testosterone levels, as other anabolic steroids contain testosterone-like drugs that are modified to increase potency or reduce side effects. One issue that is shared by all anabolic steroids is the subsequent suppression of natural testosterone production as androgen levels are maintained in the supraphysiologic (above normal) range.3,4 This suppression occurs because the body has a feedback mechanism that adjusts testosterone production to keep androgen levels in a defined range. When testosterone levels get low, regulatory glands in the brain – the hypothalamus and pituitary, send out hormonal signals that prompt the testicles to produce more testosterone. Conversely, when testosterone levels get too high, signals from the hypothalamus and pituitary drop way down and the testicles lower testosterone production. If testosterone (or other androgens) levels are elevated well above normal range and kept there for a long period of time, such as would occur during an anabolic steroid cycle, natural testosterone production is interrupted and the testicles go into a kind of hibernation.
 This is the same concept behind birth control pills used by women, as high levels of estrogen and progesterone prevent the ovaries from being stimulated to release an egg, blunting natural estrogen and progesterone production at the same time. Understanding that elevated steroid hormone levels (testosterone or estrogen and progesterone) suppress both the endocrine (steroid hormone) and reproductive (sperm or egg production) functions at the same time clarifies why anabolic steroid use can cause sterility in many men until testicular function recovers off-cycle.
Unfortunately, to gain an anabolic advantage from anabolic steroids, it is necessary to dose the drugs into a range that is often suppressive to the testicles. In fact, for muscle growth, research has shown that in the range studied, there is a definite dose-response relationship – a term that suggests more is better.5-7 However, as most steroid users learn, more is not always better. As the anabolic steroid dose(s) go up, so too does the risk of adverse side effects, such as: gynecomastia, emotional instability, hair loss, acne, impotence and other issues.8,9 Most mature anabolic steroid users with experience in using the drugs tend to use very moderate doses, ranging from 400 to 800 mg weekly (testosterone equivalent).10 Certainly, this differs from the markedly higher doses used by competitive bodybuilders who are driven to maximize muscle growth; the majority of steroid users do not compete in bodybuilding or other sports according to data from a number of surveys.10,11 Interestingly, the choice of steroid also becomes less exotic as users mature; testosterone esters or nandrolone esters predominate, possibly due to the availability of these drugs through legitimate sources or the uncertainty that accompanies the use of the less familiar, more exotic steroids that can only be sourced through black market suppliers.
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Research and Review 
