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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.

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Sports Doping

Ed Chung

May 7, 2002


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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”


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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!!!”


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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


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IOC prohibited substances

  • Anabolic agents

  • Peptide hormones, mimetics, and analogues

  • Stimulants

  • Diuretics

  • Narcotics


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Anabolic Agents

  • Enhance muscle mass gained from strength training

    - Anabolic steriods

    - Testosterone precursors


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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


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Acne

Alopecia

Testicular atrophy

Masculinization

Gynecomastia

Infertility

Mood alterations

Adverse lipid profile

Hypertension

Glucose intolerance

Premature epiphyseal closure

Anabolic steroid side effects


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Testosterone precursors

Cholesterol

Pregnenolone

17-hydroxypregnenolone

DHEA

Androstenedione

Testosterone


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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.


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Androstenedione / DHEA

  • Potential side effects similar to anabolic steroids

  • Excessive precursors shown to be aromatized to form estrogen


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Human Growth Hormone

  • Manufactured by recombinant technology for replacement in deficient patients

  • Promotes protein anabolism

  • Intramuscular delivery

  • No virilizing effects – attractive to women


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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


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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


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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


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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


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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


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Creatine side effects

  • Muscle cramps at recommended doses

  • Potential for renal insult at high doses, with a few anecdoctal reports of interstitial nephritis


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Stimulants

  • Promote CNS and muscular excitation

  • Caffeine

  • Amphetamines

  • Ephedrine (and pseudoephedrine)


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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


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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


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Caffeine

  • Tolerance develops to repeated dosing

  • Excess may cause increased anxiety, insomnia, and cardiovascular strain


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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


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Ephedrine

  • Ma Haung, ephedra

  • Increases myocardial contraction and blood pressure, decreases perception of fatigue, decreases appetite

  • Similar side effects of hyperthermia and cardiovascular strain


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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


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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


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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



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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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