Sports Doping Ed Chung May 7, 2002 Introduction In 1997, Sports Illustrated asked 198 aspiring US Olympians, “Would you take a banned performance enhancing substance if you were guaranteed to win and not get caught?” 98% said “YES” Introduction Then, when asked, “Would you take the same undetectable substance if it would contribute to winning every competition for 5 years, then result in death?” Over 50% still said “YES!!!” Prevalence Over 1,000,000 Americans have used anabolic steroids – 250,000 of them adolescents 5-14% of NCAA atheletes 35% of 11-18 yr olds believe caffeine will enhance athletic performance; 25% have used (1993 Canadian national school survey) Significant increases in creatine and androstenedione sales after 1998 MLB home run race between McGwire and Sosa IOC prohibited substances 1. Anabolic agents 2. Peptide hormones, mimetics, and analogues 3. Stimulants 4. Diuretics 5. Narcotics Anabolic Agents Enhance muscle mass gained from strength training - Anabolic steriods - Testosterone precursors Anabolic Steroids Testosterone derivatives – modified to increase anabolic effects while decreasing androgenic effects Doses may reach 100X medical replacement dose Efficacy in numerous studies since the 1970’s Anabolic steroid side effects Acne Adverse lipid profile Alopecia Hypertension Testicular atrophy Glucose intolerance Masculinization Premature epiphyseal Gynecomastia closure Infertility Mood alterations Testosterone precursors Cholesterol Pregnenolone 17-hydroxypregnenolone DHEA Androstenedione Testosterone Androstenedione / DHEA Excess quantities theoretically are metabolized to testosterone, thereby increasing serum levels. Early studies showed promise, but a recent randomized, double-blinded study of 30 men by King (1999) demonstrated no gains over placebo in testosterone levels or strength. Androstenedione / DHEA Potential side effects similar to anabolic steroids Excessive precursors shown to be aromatized to form estrogen Human Growth Hormone Manufactured by recombinant technology for replacement in deficient patients Promotes protein anabolism Intramuscular delivery No virilizing effects – attractive to women Human Growth Hormone Studies suggest increases in muscle size, but not strength (increased collagen in muscles without an increase in contractile tissue) Excess may lead to SxS of acromegaly Insulin-like Growth Factor Newer; poor in vivo data Potential anabolic and growth promoting effects similar to human growth hormone without the lipid side effects More prone to cause hypoglycemia Creatine Intrinsic fuel for anaerobic activity After ingestion, creatine readily binds to phosphorus Phosphocreatine mediates the regeneration of ATP from ADP P-Cr + ADP + H+ Cr + ATP Creatine Supplementation aimed at maximizing stores of phosphocreatine in muscle tissue Potentially decreases fatigue and increases recovery time Enhances training, but no direct anabolic effect Still legal for most competitions Creatine Some equivocal studies Others demonstrate positive effect on short, high-intensity activity - Dawson (1995), repeated short sprints - Earnest (1995) & Hamilton-Ward (1997), bench press weight Creatine side effects Muscle cramps at recommended doses Potential for renal insult at high doses, with a few anecdoctal reports of interstitial nephritis Stimulants Promote CNS and muscular excitation Caffeine Amphetamines Ephedrine (and pseudoephedrine) Caffeine The most used and abused drug in the world Variety of effects from adenosine receptor antagonism - increased catecholamines - increased lipolysis - CNS activation - improved respiratory function Caffeine Many studies of varying quality Review by Sinclair and Geiger; studies 1994-1998 selecting only those using highly trained athletes (for reproducibility of performance) with caffeine washout period - 11 studies, 115 participants - cycling/running - significant increases in time to exhaustion and decreased perception of effort Caffeine Tolerance develops to repeated dosing Excess may cause increased anxiety, insomnia, and cardiovascular strain Amphetamines Abused since 1920’s Increase alertness and produce euphoria by central modulation of dopamine and noradrenaline Side effects: psychosis, hyperthermia, cardiovascular strain Several deaths from heat stroke Ephedrine Ma Haung, ephedra Increases myocardial contraction and blood pressure, decreases perception of fatigue, decreases appetite Similar side effects of hyperthermia and cardiovascular strain Caffeine and Ephedrine Randomized, blinded, placebo study by Bell (2001) with 24 healthy, untrained men cycling to exhaustion Significant increase in power by ephedrine Significant increase in endurance by caffeine Synergistic effect Other Agents Erythropoietin - increases hematocrit to increase oxygen- carrying capacity, and thus stamina - increases blood vicosity posing risk for vascular occlusion, especially when concurrent with dehydration during exercise Other Agents Beta Blocker - reduce anxiety and tremor, but also reduces energy Diuretics - transient weight loss (e.g. wrestlers and boxers seeking a lower weight class) - risk for dehydration Conclusions Conclusions Sports doping is widespread Lack strong data on safety and efficacy Potential benefits in amateur athletes (our patients) probably negligible Unclear risks, especially on long-term use and mega dosing First, do no harm.
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