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Sports Doping

Sports Doping

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Sports Doping

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  1. Sports Doping Ed Chung May 7, 2002

  2. 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”

  3. 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!!!”

  4. 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

  5. IOC prohibited substances • Anabolic agents • Peptide hormones, mimetics, and analogues • Stimulants • Diuretics • Narcotics

  6. Anabolic Agents • Enhance muscle mass gained from strength training - Anabolic steriods - Testosterone precursors

  7. 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

  8. Acne Alopecia Testicular atrophy Masculinization Gynecomastia Infertility Mood alterations Adverse lipid profile Hypertension Glucose intolerance Premature epiphyseal closure Anabolic steroid side effects

  9. Testosterone precursors Cholesterol Pregnenolone 17-hydroxypregnenolone DHEA Androstenedione Testosterone

  10. 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.

  11. Androstenedione / DHEA • Potential side effects similar to anabolic steroids • Excessive precursors shown to be aromatized to form estrogen

  12. Human Growth Hormone • Manufactured by recombinant technology for replacement in deficient patients • Promotes protein anabolism • Intramuscular delivery • No virilizing effects – attractive to women

  13. 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

  14. 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

  15. 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

  16. 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

  17. 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

  18. Creatine side effects • Muscle cramps at recommended doses • Potential for renal insult at high doses, with a few anecdoctal reports of interstitial nephritis

  19. Stimulants • Promote CNS and muscular excitation • Caffeine • Amphetamines • Ephedrine (and pseudoephedrine)

  20. 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

  21. 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

  22. Caffeine • Tolerance develops to repeated dosing • Excess may cause increased anxiety, insomnia, and cardiovascular strain

  23. 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

  24. Ephedrine • Ma Haung, ephedra • Increases myocardial contraction and blood pressure, decreases perception of fatigue, decreases appetite • Similar side effects of hyperthermia and cardiovascular strain

  25. 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

  26. 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

  27. 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

  28. Conclusions

  29. 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.