Written by Dan Gwartney, MD
09 April 2007
Professional bodybuilding has gone through a number of eras, many of them defined by the introduction of new drugs. During the first half of the twentieth century, bodybuilders were limited to food products- cream, beef or eggs. Perhaps this was the era when genetics best determined a bodybuilder's success, such as it was, since most bodybuilders in those early years were circus strongmen. Later, food concentrates became available, items like powdered milk or desiccated liver tablets. These products provided no great improvements, but introduced the concept of performance supplements. During the ‘60s and ‘70s, anabolic steroids greatly increased the size and definition of bodybuilders, creating the physiques that still adorn the walls of many gyms. It was the ‘80s that changed the look of the sport from comic book superhero to the more exaggerated and grotesque look of the comic book super villains.

     For Better or Worse
The 1980 Mr. Olympia was perhaps the most controversial and newsworthy in the history of the event. In addition to the return of a champion, the 1980 Olympia was the first in which there were rumors of growth hormone (GH) abuse among the competitors. Since then, the appearance of the competitors has changed; some say for the better, others say for the worse. Today's bodybuilders are larger and leaner than ever before, though it has been at the expense of symmetry and aesthetics. This is due in large part to the effects of GH, but other drugs have impacted the sport since 1980, including insulin and Synthol.

GH is widely regarded by athletes in many sports for its anabolic effects.1-5 GH will increase the size of many tissues and organs in the body, including muscle tissue. Unfortunately, the increase in muscle size seen with GH use is not associated with an equal increase in strength.5,6 In fact, some studies have shown that GH use actually reduces exercise tolerance.7 This is due to the fact that the increase in muscle size is not a reflection of greater contractile protein (the functional proteins in muscle that cause flexion and extension); rather, it's due to an increase in non-contractile protein.2,6 For use as an anabolic, bodybuilders discovered that GH had a dose-related response; in other words, more drug = more growth.

However, as would be expected in a potent drug, GH abuse in excessive doses used by many of the pros (as much as 15 IU/day) led to undesirable side effects. Bodybuilders were once known for having a perfect "V" shape: Broad shoulders, thick chest, narrow waist and athletic legs. Now, it's difficult to find a pro without a distended abdomen; despite having minimal body fat, few have a discernible "six-pack." Why? While it has not been documented in the medical literature, it is certainly due to a condition known as organomegaly, the abnormal growth of organs.8 Undoubtedly, these bodybuilders have pathologically enlarged hearts, livers, intestines and other organs, straining the abdominal cavity like a nine-month pregnancy. Some also show changes in their facial bones, a related change that's part of the broader condition, termed "acromegaly".8

The problems of GH excess have been studied as a consequence of natural causes, not as a result of GH abuse. People with a certain type of brain tumor (functional pituitary adenoma) account for most cases.8 If this condition occurs during childhood, it is known as gigantism; if it begins in adulthood, it is known as acromegaly. The difference is due to the closure of the bones' growth plates during adolescence; excess GH released during childhood can result in an adult height of seven feet or more. Former wrestling superstar "Andre the Giant" suffered from gigantism prior to his early death at the age of 46. In contrast, the 1940s film star Rondo "The Creeper" Hatton, suffered from acromegaly, having distorted features, but normal height. Pictures of these two may be viewed at fan websites.9,10 Comparing these photos to the facial features of many of today's pros will reveal subtle similarities.

High dose GH protocols carry a heavy burden, not only creating a monstrous appearance, but also greatly increasing the likelihood of a premature death. Most people who suffer from gigantism or acromegaly die in their forties or fifties due to heart complications.8 This tragedy can be avoided in athletes, as many benefits of GH can be obtained from safer, low-dose protocols.11,12 Many bodybuilders use low-dose regimens of GH for its potent lipolytic (fat burning) effect, finding it very effective, especially when used in combination with other drugs.13,14  

Body Fat Control
GH is most commonly the product "22 kD recombinant human growth hormone monomer," meaning it's created through synthetic means, to mimic the GH produced in the human pituitary (a small gland in the brain). Most GH is typically packaged as a sterile crystalline powder, which is mixed with sterile water just prior to injection. Many GH products are listed by weight, yet most dosing information is listed according to IU (International Units). For many products, one milligram is approximately three IU. Early GH products were obtained from cadavers (dead people) and the use of cadaveric GH carried a high risk for transmitting serious disease.5,13

GH is commonly prescribed either to children with growth delays or people who have had brain surgery, interrupting natural GH production.6,8 Numerous studies have shown that replacing GH in GH-deficient people reduced body fat and increased lean mass.2,6,15 Further, it has been shown that in comparison, people with acromegaly are leaner and have more lean mass than "normal" people; GH-deficient people have greater body fat and less lean mass.6,16-18 Thus, from the data provided by these "experiments of nature" it would appear that body fat levels can be controlled somewhat by GH levels, supporting the idea of using GH as a cutting drug. Unfortunately, what has not been defined is the dose range that may be effective in reducing body fat, without increasing the risk for abnormal organ growth or other harmful conditions.

Several studies have reviewed the effect of GH therapy in obese individuals.19-23 Unfortunately, these studies do not directly apply to athletes, as it has been shown that obese people often have a blunted response to GH or signals that influence GH release.20,22,24,25 Further, these investigational studies were controlled to study the effect of GH alone, whereas most athletes who use GH are also using a number of other drugs and exercise vigorously.1,3,13,26-28

Evidence from the clinical studies and reports from the field of athletes who have used GH would support a claim that GH can lower body fat in healthy adults using as little as six to 10 IU per week.11-13,20,21,29,30 However, the dosing of GH requires a commitment to discipline if it is to be effective, as GH clears the system quickly; in fact it is undetectable within 24 hours.1,4

This requires the user to inject GH twice a day, dividing the dose accordingly. Many people injected GH less frequently, often resulting in less effective treatment and greater onset of side effects (e.g., carpal tunnel syndrome).12,31 GH can be injected under the skin (subcutaneous), rather than into the muscle, making it less painful and more convenient. It has been reported that the subcutaneous injections need to be placed at different areas to avoid pocketing under the skin from local, aggressive fat loss, which can occur if GH is injected frequently in one site.13

It appears the body may respond better to GH with higher levels or longer exposure, suggesting there may be some benefit to its use in normal individuals.3,32 GH affects nearly every system in the body, increasing cellular function and affecting the actions of enzymes and receptors. One mechanism of fat loss purported in the medical literature is a greater sensitivity and fat loss response to norepinephrine.33 The norepinephrine pathway is the way most stimulants cause fat loss, including drugs like clenbuterol and ephedrine.

    How GH Stacks Up
While the effects of low-dose GH will not be as rapid or dramatic as compared to high-dose GH, many bodybuilders report success by "stacking" GH with other potent cutting drugs.13  GH treatment may cause active thyroid hormone levels to decrease; thus, many bodybuilders include some form of thyroid hormone in their "cutting stack."31 Cytomel (T3) is most commonly used, but great care is necessary, as high levels of T3 can cause a number of serious side effects and lead to muscle wasting.34,35

As both GH and T3 increase the body's sensitivity to stimulants, stimulant drugs will provide greater fat loss, but there is also a greater risk of side effects. It may be possible to achieve more fat loss with the combination of low doses of the three drugs combined (GH, T3 and ephedrine/caffeine), than using high doses of any one of the above. Further, it may be possible to lose fat without cutting calories dramatically, as GH will block the "fat building" effect of insulin.26

Many bodybuilders have made a practice of using insulin while on GH.13,31 This is not necessary, nor should it be considered, when using GH for fat loss. When insulin is used, it's to amplify the anabolic signal of insulin during high-dose GH use, as high doses of GH make the body resistant to insulin's signal. In the fat cell, insulin and GH act in opposite directions; GH promoting fat loss, insulin promoting fat gain. However, in the muscle, GH and insulin act together to promote muscle gains.1,14,36 In muscle, GH prevents muscle breakdown or catabolism (and may increase muscle growth through IGF-1), while insulin increases the anabolic growth of muscle. This explains why higher insulin levels may be desirable during a bulking cycle, but are not wanted during a cutting cycle.

Lastly, it is generally accepted that GH increases the gains seen with anabolic steroids. Testosterone appears to have a relationship with GH, as higher levels of GH are released when testosterone levels are also elevated.26,37 It may be wise to avoid using heavily androgenic steroids or high doses, as GH therapy has been shown to cause or aggravate gynecomastia.38,39  

GH is being used by bodybuilders and other athletes to create the exaggerated physiques that are the hallmark of today's professional sportsmen. In the race for titles and medals, these athletes inject high doses of GH, becoming markedly larger and leaner, but experiencing serious side effects that had only been seen in rare medical disorders. Distended abdomens and distorted facial features are becoming commonplace, making a mockery of these victims of excess. While the anabolic effects of GH relate to the dose, with higher doses realizing greater gains, the cutting effect of GH can be realized with low doses of the drug. As little as one or two IU per day (usually divided into two doses) may be able to accelerate fat loss.

GH treatment is often tracked by following serum (blood) levels of IGF-1, a hormone produced by the liver in response to GH. Optimal benefits seem to be experienced when IGF-1 is maintained in the range or 300-500, with side effects becoming more prevalent as levels increase beyond this range.12 Multiple daily injections are inconvenient and problematic, but there are sustained-release GH formulations being developed, providing hope that GH treatment can be provided on a more convenient weekly or monthly schedule.40,41 A number of pharmaceutical GH secretagogues (chemicals that stimulate natural GH release) are being developed, which may offer similar benefits using an oral or spray delivery.42,43 Most GH-releasing supplements have proven to have little or no effect.

    Summing Up
GH is a potent means of cutting fat, even when used in moderate dose. GH is reported to work best in concert with other fat-burning drugs, including T3 and ephedrine/caffeine. Care should be taken to use these three drugs at the lowest effective dose, as side effects are more common and more serious with higher doses. While many of the side effects may be temporary, some can be permanent, or even deadly. Athletes considering GH should take great care before making such a decision, as there are serious health, legal and competitive consequences.

GH use was considered non-detectable, but that is no longer the case. Drug-testing laboratories now have the ability to detect GH abuse.1 There have been many reports of fraudulent, counterfeit GH products being sold, even through U.S. pharmacies.44 This will continue, as the price of GH is very high, offering a substantial profit to unscrupulous dealers and distributors.
GH is an expensive drug with a high level of risk for permanent, disfiguring and life-shortening side effects. Thankfully, its cost keeps it out of the hands of amateurs. Hopefully, a fuller understanding of the physiology of GH will prevent those who do choose to use the drug from abusing it in the current high-dose regimens being followed by today's athletes. Anti-aging physicians and endocrinologists have found that lower doses can be equally effective, particularly when used alongside other supportive drug therapy. A greater knowledge of the risks of high-dose GH should decrease the incidence of acromegalic athletes.

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