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Published byIris Moody Modified over 9 years ago
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In the news…. ► Sinkewitz (sacked in TdF for +ve testosterone test in training) admits using banned blood transfusions and EPO since 2003 ► Kashechkin (+ve TdF for homologous blood doping) Privately run sports bodies (UCI and WADA) no legitimate right to test athletes Contravenes Europes declaration Human Rights Only public bodies (eg. Governments) have legitimate right to test athletes ► Watch this space……
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Prohibited Substances ► In and out of comp. Other Anabolic Agents Other Peptide Hormones Beta-2 Agonists Agents with anti-oestrogenic activity Diuretics and other Masking Agents ► In comp. Stimulants Narcotics Cannabinoids Glucocorticosteroids
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Other Anabolic agents ► E.g clenbuterol ► A Β 2 Agonist – similar to salbutamol. Used tx asthma (not in UK). ► Numerous positive cases ► Evidence promotes skeletal muscle growth (10- 12%) in rats with 2 weeks tx (Yang and McElliott 1989) ► But effect in animals is with 100x tolerable dose in humans ► Inhibits protein catabolism ► Equivocal results in human studies ► Side effects – tremor, restlessness, ↑ bp, headache Purported to reduce after 8-10d Downregulation of receptors
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Peptide Hormones ► Corticotrophins (ACTH) to increase corticosteroid levels – anti-inflammatory and mood enhancing; ► Gonadotrophins to counter androgenic anabolic steroid effects; ► hGH – used for anabolic properties, able to train harder and promote recovery; ► Insulin (unless certified IDDM) ► EPO – separate lecture.
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Human Growth Hormone ► Increases growth in pre-adolescents (clinical use) ► Stimulates production of insulin-like growth factors (IGLF-1 and IGLFD-2) ► Some effect on muscle growth (via IGF-1) ► Increases amino acid and glucose uptake into muscle ► Increases fat breakdown (glycogen sparing) ► hGH increases following exercise ► Detection difficult due to similarity between endogenous and rhGH – short ½ life (20 mins) – returns to baseline within 16 – 20 hrs
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Why take hGH? ► Few controlled studies: Deyssig et al., (1993) reduction fat mass, no diff strength; Yarasheski et al., (1993) no increase muscle protein synthesis in weight lifters cf. placebo ► Adverse effects – acromegaly, DM, hypertension, reduced HDL, osteoporosis, menstrual irregularities, impotence
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Narcotics ► Act on brain to reduce pain from injury & go thru pain threshold ► Addictive ► Illegal in most countries ► Illegal opiates – morphine, heroine, pethidine, dextropropoxyphene ► Legal – Dextromethorphan, codeine (analgesics and diarrhoea suppressants)
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Cannabinoids ► Tetrahydrocannabinol (THC) ► Renaud and Cormier (1986) – reduction in max performance ► Doping? Calming, improved sleep
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Β 2 Agonists ► Used in treatment of asthma, EIA as potent bronchodilators. ► Eg. Salbutamol (Ventalin), short acting, also eg. Clenbuterol, long-acting ► Some reclassified into ‘Other anabolic agents’ due to poss. anabolic effect ► Use restricted to inhaler only with TUE from physician prior to competition Formoterol, salbutamol, salmeterol, terbutaline Salbutamol >1000ng.ml adverse finding
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Do inhaled β 2 agonists affect performance?
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Do β 2 agonists affect performance? ► Oral admin of salbutamol may increase muscle strength (Martineau et al., 1992; van Baak et al., 2000) Endurance (van Baak et al., 2000, Collomp et al., 2000) But much larger dose (10 – 20x inhalation)
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Hormone antagonists and modulators ► Aromatase inhibitors ► Ostrogen receptor modulators eg. tamoxifen ► Anti-oestrogenic substances E.g. Clomiphene, cyclofenil – used after steroids to stimulate own production of testosterone ► Agents modifying myostatin function: myostatin inhibitors
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Masking Agents ► Eg. Acetazolamide – diuretic decreases urinary output of some drugs for short periods ► Epitestosterone ► Probenecid – anti-gout banned by IOC but not banned by IOC but not UCI until after 1988 tour ► Plasma expanders
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Diuretics
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Diuretics Elimination of fluid from the body Used illegally in sport to: ► Meet weight limit; ► Overcome fluid retention from use of anabolic steroids; ► Increase volume of urine Side effects: dehydration, faint, muscle cramps, headaches, nausea.
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Glucocorticosteroids ► Eg. Cortisol, cortisone ► Produced by adrenal cortex (from cholesterol) ► Feedback mech between hypothalamus (corticotropin releasing factor); ant pit (adrenocorticotropic hormone (ACTH)); and adrenal cortex (cortisol) ► Widely used for injuries - Potent anti-inflammatories despite limited evidence of benefits of glucocorticosteroid use in acute injuries in sport (Dvorak et al., 2006) ► Open airways, mask injury, increase ability to train. ► Stim gluconeogenesis, mobilisation amino acids and fatty acids ► Prohibited orally, rectally, iv or intramuscular – unless with TUE (common request) ► Allowed – dermatological, aural/otic, nasal, buccal cavity, opthalmologic disorders ► Serious toxic effects with prolonged use. ► Soetens et al., (1995) – no evidence of ACTH on max performance ► Insufficient evidence for substantial benefits of glucocorticosteroids in tx of sport related injuries
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Prohibited Methods ► Enhancement of oxygen transfer – separate lecture; ► Pharmacological, chemical and physical manipulation; ► Gene doping.
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Substances prohibited in particular sports ► Alcohol ► Beta-blockers
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Beta-2 Agonists What are beta and alpha receptors ? Adrenaline 1 2 1 2 3 Pupil dilation Vasoconstriction Increased heart rate bronchodilation lipolysis Note adrenalin = epinephrine
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Comparison of hormones and neurotransmitters
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How a receptor mediates an effect
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How alpha and beta agents work
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How beta blockers work
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Beta-2 agonists Banned unless have therapeutic use exemption Cannot use at poolside Salbutamol, terbutaline 2 bronchodilation
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Beta-2 agonists Known cases of bans British weightlifters 1992 Olympics Katrine Krabbe (German 100 m sprinter). 4 year ban reduced to 2 years on appeal Clenbuterol (asthma medication in Europe, not UK) 2 Bronchodilation and anabolic effects (increases muscle mass and fat metabolism in animals)
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Refs ► British Journal Sports Med (2006) 40 (Suppl I)
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