Effects of androgenic-anabolic steroids in athletes.For the past 50 years anabolic steroids have been at the forefront of the controversy surrounding performance enhancing drugs. For almost half of this time no attempt was made by sports governing bodies to control its use, and only recently have all of the major sports governing bodies in North America agreed to ban from competition and punish athletes who test positive for anabolic steroids. These punitive measures were developed with the primary concern for promotion of fair play xteroids eliminating potential health risks associated with androgenic-anabolic steroids. Yet, controversy exists androgenic anabolic steroids ncbi these testing boldenone undecylenate test cypionate deter anabolic steroid use. Although the scope of this paper androgenic anabolic steroids ncbi not focus on the effectiveness of testing, or the issue of fair play, it is of interest to understand why many athletes underestimate the health risks associated from these drugs.
Medical Issues Associated with Anabolic Steroid Use: Are They Exaggerated?
For the past 50 years anabolic steroids have been at the forefront of the controversy surrounding performance enhancing drugs. For almost half of this time no attempt was made by sports governing bodies to control its use, and only recently have all of the major sports governing bodies in North America agreed to ban from competition and punish athletes who test positive for anabolic steroids.
These punitive measures were developed with the primary concern for promotion of fair play and eliminating potential health risks associated with androgenic-anabolic steroids. Yet, controversy exists whether these testing programs deter anabolic steroid use. Although the scope of this paper does not focus on the effectiveness of testing, or the issue of fair play, it is of interest to understand why many athletes underestimate the health risks associated from these drugs.
What creates further curiosity is the seemingly well-publicized health hazards that the medical community has depicted concerning anabolic steroidabuse. The focus of this review is to provide a brief history of anabolic steroid use in North America, the prevalence of its use in both athletic and recreational populations and its efficacy. Primary discussion will focus on health issues associated with anabolic steroid use with an examination of the contrasting views held between the medical community and the athletes that are using these ergogenic drugs.
Existing data suggest that in certain circumstances the medical risk associated with anabolic steroid use may have been somewhat exaggerated, possibly to dissuade use in athletes. Anabolic-androgenic steroids herein referred to as only anabolic steroids are the man-made derivatives of the male sex hormone testosterone.
Physiologically, elevations in testosterone concentrations stimulate protein synthesis resulting in improvements in muscle size, body mass and strength Bhasin et al. In addition, testosterone and its synthetic derivatives are responsible for the development and maturation of male secondary sexual characteristics i. Testosterone was isolated in the early 20 th century and its discovery led to studies demonstrating that this substance stimulated a strong positive nitrogen balance in castrated dogs and rats Kochakian, Testosterone, because of its rapid degradation when given through either oral or parenteral administration, poses some limitations as an ergogenic aid.
Although its potency is rapidly observed, the high frequency of administration needed becomes problematic. In addition, testosterone has a therapeutic index of 1 meaning there is similarity in the proportion between the anabolic and androgenic effects.
As a result it becomes necessary to chemically modify testosterone to retard the degradation process and reduce some of the negative side effects. This allows for maintenance of effective blood concentrations for longer periods of time, may increase its interaction with the androgen receptor, and achieves the desired anabolic and androgenic changes.
Boje, was the first to suggest that exogenous testosterone administration may enhance athletic performance. The first dramatic reports of anabolic steroid use occurred following the world weightlifting championships Yesalis et al.
Wide spread use has also been reported in power lifters Wagman et al. The ergogenic effects associated with anabolic steroids are presented in Table 1. The rationale for stacking is to increase the potency of each drug. That is, the potency of one anabolic agent may be enhanced when consumed simultaneously with another anabolic agent.
They will use both oral and parenteral compounds. Most users will take anabolic steroids in a cyclic pattern, meaning the athletes will use the drugs for several weeks or months and alternate these cycles with periods of discontinued use. Often the athletes will administer the drugs in a pyramid step-up pattern in which dosages are steadily increased over several weeks.
At this point, some athletes will discontinue drug use or perhaps initiate another cycle of different drugs i. A recent study has shown that the typical steroid regimen involved 3. The dose that the athlete administers was reported to vary between 5 - 29 times greater than physiological replacement doses Perry et al. These higher pharmacological dosages appear necessary to elicit the gains that these athletes desire.
In a classic study on the dose-response curve of anabolic steroids, Forbes, demonstrated that the total dose of anabolic steroids have a logarithmic relationship to increases in lean body mass.
Adverse effects associated with anabolic steroid use are listed in Table 2. For years, the medical and scientific communities attempted to reduce anabolic steroid use by athletes by underscoring their efficacy and focusing on the unhealthy side effects Biely, ; Darden, ; Fahey and Brown, ; Fowler et al. However, recent literature has suggested that the medical issues associated with anabolic steroids may be somewhat overstated Berning et al.
It is important to note that there are differences in the side effects associated with anabolic steroid use i. The clinical examination of anabolic steroid use is quite limited. Much of the problem in prospectively examining the effects of anabolic steroids on the athletic population is related to the unwillingness of institutional review boards to approve such studies in a non-clinical population.
As a result, most of the investigations concerning medical issues associated with anabolic steroid administration have been performed on athletes self-administering the drugs. Anecdotally, it appears that a disproportionate magnitude of use and incidence of adverse effects are evident in bodybuilders who are also known for consuming several other drugs that relieve some side effects but potentiate other risk factors as well, i. The mindset and motivation of these two types of athletes can be quite different.
They will generally cycle the drug to help them reach peak condition at a specific time of the training year. In contrast, bodybuilders use anabolic steroids to enhance muscle growth and definition. Their success is predicated on their aesthetic appearance. Recent research has indicated that those athletes exhibit behavior that are consistent with substance dependence disorder Perry et al.
Although the medical issues associated with anabolic steroids may be quite different between these two types of athletes, the scientific literature generally does not differentiate between the two.
The following sections will discuss adverse effects on specific physiological systems associated with anabolic-androgenic steroid use. It is important to note that many athletes consume multiple drugs in addition to anabolic steroids. Thus, the unhealthy side effects could be potentiated by the use of drugs such as human growth hormone or IGF In both the medical and lay literature one of the principal adverse effects generally associated with anabolic steroid use is the increased risk for myocardial infarction.
However, direct evidence showing cause and effect between anabolic steroid administration and myocardial infarction is limited. Many of the case studies reported normal coronary arterial function in anabolic steroid users that experienced an infarct Kennedy and Lawrence, ; Luke et al.
Interestingly, in most case studies the effects of diet or genetic predisposition for cardiovascular disease were not disseminated and could not be excluded as contributing factors. Alterations in serum lipids, elevations in blood pressure and an increased risk of thrombosis are additional cardiovascular changes often associated with anabolic steroid use Cohen et al.
The magnitude of these effects may differ depending upon the type, duration, and volume of anabolic steroids used. Interesting to note is that these effects appear to be reversible upon cessation of the drug Dhar et al. In instances where the athlete remains on anabolic steroids for prolonged periods of time e. Sader and colleagues noted that despite low HDL levels in bodybuilders, anabolic steroid use did not appear to cause significant vascular dysfunction.
Interestingly, athletes participating in power sports appear to have a higher incidence of cardiovascular dysfunction than other athletes, regardless of androgen use Tikkanen et al. However, anabolic steroid-induced changes in lipid profiles may not, per se, lead to significant cardiovascular dysfunction. The risk of sudden death from cardiovascular complications in the athlete consuming anabolic steroids can occur in the absence of atherosclerosis.
Thrombus formation has been reported in several case studies of bodybuilders self-administering anabolic steroids Ferenchick, ; Fineschi et al. Climstein and colleagues demonstrated that highly strength-trained athletes, with no history of anabolic steroid use exhibited a higher incidence of wave form abnormalities relative to recreationally-trained or sedentary individuals. However, when these athletes self-administered anabolic steroids, a higher percentage of wave form abnormalities were exhibited.
Further evidence suggestive of left ventricular dysfunction has been reported in rodent models. A study on rats has shown that 8 weeks of testosterone administration increased left ventricle stiffness and caused a reduction in stroke volume and cardiac performance LeGros et al. It was hypothesized that the increased stiffness may have been related to formation of crosslinks between adjacent collagen molecules within the heart. Others have suggested that anabolic steroid use may suppress the increases normally shown in myocardial capillary density following prolonged endurance training Tagarakis et al.
However, there are a number of interpretational issues with this study. The changes reported were not statistically significant. In addition, the exercise stimulus employed prolonged endurance training is not the primary mode of exercise frequently used by anabolic steroid users.
Resistance training, independent of anabolic steroid administration, has been shown to increase left ventricular wall and septal thickness due to the high magnitude of pressure overload Fleck et al. This is known as concentric hypertrophy and does not occur at the expense of left ventricular diameter.
In general, cardiac hypertrophy resulting from a pressure overload, i. Therefore, the potential for a reduction in coronary vasculature density exists for the resistance- trained athlete. However, it does not appear to pose a significant cardiac risk for these athletes. Recent observations have shown a dose-dependent increase in left ventricular hypertrophy LVH in anabolic steroid users Parssinen and Seppala, This may have the potential to exacerbate the reduction in coronary vasculature density.
However, the authors have acknowledged that their results may have been potentiated by a concomitant use of human growth hormone by their subjects.
Other studies have failed to show additive effects of anabolic steroid administration and LVH in resistance-trained athletes Palatini et al. An elevated risk for liver tumors, damage, hepatocellular adenomas, and peliosis hepatitis are often associated with anabolic steroid use or abuse.
This is likely due to the liver being the primary site of steroid clearance. In addition, hepatic cancers have been shown to generally occur with higher frequency in males compared to females El-Serag, It is thought that high endogenous concentrations of testosterone and low estrogen concentrations increase the risk of hepatic carcinomas Tanaka et al. However, this appears to be prevalent for men with pre-existing liver disease. In normal, healthy men the relationship between testosterone concentrations and liver cancer has not been firmly established.
Additional reports of liver cancer and anabolic steroids have been reported in non- athletic populations being treated with testosterone for aplastic anemia Nakao et al. In regards to liver cancer and disease in athletes consuming anabolic steroids, many concerns have been raised based primarily on several case studies that have documented liver disease in bodybuilders using anabolic steroids Cabasso, ; Socas et al.
A few studies have recently questioned the risk to hepatic dysfunction from anabolic steroid use Dickerman et al. A recent study examining the blood chemistry of bodybuilders self-administering anabolic steroids reported elevations in aspartate aminotransferase AST , alanine aminotransferase ALT and creatine kinase CK , but no change in the often-regarded more sensitive gamma- glutamyltranspeptidase GGT concentration Dickerman et al.
Thus, some experts have questioned these criteria tools because of the difficulty in dissociating the effects of muscle damage resulting from training from potential liver dysfunction. This has prompted some researchers to suggest that steroid-induced hepatotoxicity may be overstated. Another study involved a survey sent to physicians asking them to provide a diagnosis for a year-old anabolic steroid using bodybuilder with abnormal serum chemistry profile elevations in AST, ALT, CK, but with a normal GGT Pertusi et al.
Thus, evidence appears to indicate that the risk for hepatic disease from anabolic steroid use may not be as high as the medical community had originally thought although a risk does exist especially with oral anabolic steroid use or abuse. The issue of anabolic steroids and bone growth has been examined in both young and adult populations.
In both populations, androgens have been successfully used as part of the treatment for growth delay Albanese et al. Androgens are bi-phasic in that they stimulate endochondral bone formation and induce growth plate closure at the end of puberty. The actions of androgens on the growth plate are mediated to a large extent by aromatization to estrogens Vanderschueren et al. Anabolic steroid use results in significant elevations in estrogens thought to impact premature closure of the growth plate.