Sports Doping (PowerPoint) by pengxiuhui

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									Sports Doping

           Ed Chung
               May 7, 2002
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”
Then, when asked,

    “Would you take the same undetectable
 substance if it would contribute to winning
 every competition for 5 years, then result in

          Over 50% still said “YES!!!”
   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
3.   Stimulants
4.   Diuretics
5.   Narcotics
            Anabolic Agents
   Enhance muscle mass gained from strength
    - 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
    Anabolic steroid side effects
   Acne                    Adverse lipid profile
   Alopecia                Hypertension
   Testicular atrophy      Glucose intolerance
   Masculinization         Premature epiphyseal
   Gynecomastia             closure
   Infertility
   Mood alterations
    Testosterone precursors
    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
    Androstenedione / DHEA
 Potential side effects similar to anabolic
 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
 Intrinsic fuel for anaerobic activity
 After ingestion, creatine readily binds to
 Phosphocreatine mediates the regeneration
  of ATP from ADP

    P-Cr + ADP + H+          Cr + ATP
 Supplementation aimed at maximizing
  stores of phosphocreatine in muscle tissue
 Potentially decreases fatigue and increases
  recovery time
 Enhances training, but no direct anabolic
 Still legal for most competitions
 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
 Promote CNS and muscular excitation
 Caffeine
 Amphetamines
 Ephedrine (and pseudoephedrine)
 The most used and abused drug in the world
 Variety of effects from adenosine receptor
  - increased catecholamines
  - increased lipolysis
  - CNS activation
  - improved respiratory function
 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
 Tolerance develops to repeated dosing
 Excess may cause increased anxiety,
  insomnia, and cardiovascular strain
 Abused since 1920’s
 Increase alertness and produce euphoria by
  central modulation of dopamine and
 Side effects: psychosis, hyperthermia,
  cardiovascular strain
 Several deaths from heat stroke
 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
 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
               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
 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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