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Performance Enhancing Substances aka Ergogenic Substances. Kevin deWeber, MD, FAAFP Director, Primary Care Sports Medicine Fellowship USUHS. Adapted from: Scott A. Playford MD, Garry Ho MD. Objectives. Discuss what an ergogenic aid is Discuss why this is important
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Performance EnhancingSubstancesaka Ergogenic Substances Kevin deWeber, MD, FAAFP Director, Primary Care Sports Medicine Fellowship USUHS Adapted from: Scott A. Playford MD, Garry Ho MD
Objectives • Discuss what an ergogenic aid is • Discuss why this is important • Discuss specific examples • Stay awake…
Ergogenic Aid - Defined • Substance or device that enhances energy production, use, or recovery and provides an athlete with a competitive advantage.
Ergogenic Aid - Examples • Mechanical(shoes) • Psychological(hypnosis) • Physiologic(blood doping) • Nutritional(creatine) • Pharmacologic(anabolic steroids)
Why do athletes use supplements? • Provide more convenient form of nutrient • Prevent a perceived deficiency • Provide direct ergogenic effect • Belief that every top athlete is taking it; they can’t afford to lag behind
Many athletes will do whatever it takes to win… • In 1995, 198 Olympic-level power athletes were given this scenario: • You are offered a banned substance with 2 guarantees: • You will not be caught • By taking the substance you will win Only 3 declined!
…at any cost • The same 198 athletes were offered a banned substance with 2 additional guarantees: • You will win every event for the next 5 years • You will die at the end of those 5 years 50% still said they would use it!
Prevalence 1996-1999 10,449 boys and girls age 12-18 surveyed: • 4.7% of boys and 1.6% of girls used protein powder or shake, creatine, amino acids/HMB, DHEA, growth hormone, or anabolic steroids at least weekly to improve appearance or strength
Placebo effect in athletes • Athletes are HIGHLY suggestible • 97% believe placebo effect works • 73% said they had experienced it • Beedie CJ. J Sports Sci Med 2007 • “Expectancy Effect” is significant • Belief in efficacy performance improvement • Pill Colors red/orange/yellow stimulant • Injection > pill • Expensive > cheap
Nocebo effect in athletes • Belief that a substance negatively affects performance • 1.57% slower 3x30sec sprints from nocebo • Beedie et al.
Anabolic Steroids • Analogs of testosterone • More than 100 types • Forms: • Oral • Injection • Topical (gels, creams) • Prevalence 2009 • Jr high: 2% • 12th grade: 5% (males 7%, >females 2%)
Anabolic Steroids – Proven Effects • Increase in fat-free mass • Increase in body weight • Increase in arm girth • Increase in leg girth • Increase in bench press and squat scores • Increase in libido
Anabolic Steroids—Disproven Effects • No effect on endurance exercise • Males on treadmill • Eur J Appl Physiol 2006 • VO2max in rats • Med Sci Sports Exer 2004
Anabolic Steroids - Side Effects • Hepatocellular damage • Cardiovascular disease (stroke, MI) • Psychological disturbance Effects can sometimes be permanent!
“Side effects of anabolic androgenic steroids abuse”Followed body builders for 2 years • Decr LH, FSH, SHBG • Decr sperm count and fertility index • Decr HDL (57 42) • No change liver/prostate US, hematological indices
More side effects… • Men • Acne • Premature baldness • Prostatic hypertrophy • Prostatitis • *Injection complications • Testicular atrophy • *Impotence • *Gynecomastia
More side effects… • Adolescents • Premature closure of physes • Decreased libido • Depression
More side effects… • Women • Clitoral enlargement • Menstrual dysfunction • Male-pattern baldness • *Masculinization • Deepening of voice • *Hirsutism
Side effects that can be PERMANENT • Premature growth plate closure • Testicular atrophy • Gynecomastia • Male pattern baldness • Female masculinization • Excessive hair growth • Deepening voice • Clitoral enlargement
Anabolic Steroid regulation • Illegal except by prescription • Banned by the USADA, NCAA, NFL, NBA, and MLB
Prohormones • Precursors of testosterone • Androstenedione • Dehydroepiandrosterone • Androstenediol
Prohormones – the evidence • No improvement in strength or lean body mass • *Causes positive urine test for steroids
Prohormones - Side Effects • May be similar to anabolic steroids, but probably less frequent.
Prohormone regulation • Anabolic Steroid Control Act of 2004 • prohormones classified as controlled substances • Banned • USADA, NCAA, NFL, NHL, NBA, MLS
Stimulants • Caffeine • Amphetamines • Cocaine • Sympathomimetics • Ephedrine • Pseudoephedrine • Phenylephrine • Phenylpropanolamine (PPA) • Modafinil (Provigil)
Stimulant Use Prevalence • Ephedrine: • 3.5% in NCAA athletes • Clin J Sports Med 2001 • 12% of HS boys/26% of girls have tried • Med Sci Sports Exer 2002 • Caffeine • 33% of British club track/field athletes • 60% of British club cyclists • Chester N, Int J Sports Med 2008
Caffeine’s Proven Effects • Increased time to fatigue (”capacity”) in wide range of lab protocols • Prolonged submaximal (> 90 min) • Sustained high-intensity (20-60 min) • Short-duration supra-max (1-5 min) • Likely beneficial in endurance and “stop-n-go” sports • No clear benefit in strength/power events
Caffeine in Endurance Running • 4.2-sec faster 1.5-km • 1-3% faster 5-km • 24-sec faster 8-km • 50-sec faster 10-km military pack march • No change in 21-km race • Improved treadmill time-to-exhaustion in marathoners
Caffeine in Other Sports • Rowing: 1-3% faster 2000m race • Swimming: 24-sec faster 1500m race • About 21 min • Cycling: 3.5% higher mean power in 40km race
Caffeine Dosing • Doses 2-9 mg/kg in studies • 2-5 mg/kg usually effective • 250-500 mg • Cola: 40 mg • Coffee: 100 mg • Tea: 20-100 mg • Red Bull: 115 mg • Vivarin: 200 mg • No difference in fx between “users” and “non-users”
Caffeinated Sports Drinks • No proven performance benefit • 18-km run times • Pl vs carb drink vs carb+150mg caffeine • consumed 4x in race • Int J Sports Med 2005
Ephedrine • 78-sec faster 10-km run (with backpack & helmet) vs placebo • 30-sec faster than caffeine • -0.8 mg/kg • No benefit when added to caffeine
Modafinil • Cycling at 85% VO2max • 22% longer time to exhaustion vs Placebo • 18.3 min vs 15.6 • Central mechanism: decreased RPE • Dose 4 mg/kg • No side-efx seen
Stimulant Mechanisms of Action • Not conclusively known • Likely: CNS-regulated decreased perceived exertion
Stimulants - Side Effects • Anxiety* • Dysrhythmias* • Hypertension* • Hallucinations • Addiction • Death
Stimulant regulation • Many prohibited by WADA & NCAA • Most ADHD meds • Some still allowed (cold meds) • Pseudephedrine, PPA • Caffeine • WADA: no longer monitored • NCAA < 15 mcg/ml • 1 cup coffee = 100mg = 1.5 mcg/ml in urine
Blood Doping • Increasing the number of red blood cells in the body to increase the oxygen carried to muscle • Administration of blood, red blood cells, or related blood products • Erythropoietin • Stimulates bone marrow to produce red blood cells
Blood Doping – proven effects • Increased Endurance • 7% increase in Hgb • 5% increase in VO2 max • 34% increase in time to exhaustion at 95% VO2 max • 44 second improvement in 5 mile treadmill run time (Williams and Branch summarized study findings)
Blood Doping - Side Effects • Infections with transfusions • Increased viscosity of blood • Stroke, MI, PE
Blood Doping - regulation • Erythropoietin only by prescription • Doping prohibited by WADA, NCAA • Blood tested for antigens • Ceiling on allowable Hct level at 50
Beta-2-Agonists • Physiology • Bronchodilation, tachycardia • Examples: albuterol, terbutaline, salmeterol
Beta-2-Agonists – proven effects • Clear benefit in asthma and EIB • No increase in ventilation of performance in studies of NON-asthmatic athletes • Clenbuterol: anabolic (25% as effective as anabolic steroids) • Side effects: tremor, tachycardia • Regulation • WADA: most prohibited • NCAA: inhalation permitted
Beta blockers • Physiology • Decreased heart rate, reduced tremor, lower BP • Examples • Atenolol • Metoprolol • Propranolol • Efficacy in sports • Proven improved scores in shooting sports
Beta blockers • Side effects • Hypotension, bronchospasm, bradycardia • Regulation • NCAA: banned in Rifle sports • WADA: banned in… • Aeronautic, archery, autos, billiards, bobsled, boules, bridge, curling, golf, gymnastics, motorcycling, modern pentathlon, powerboating, bowling, sailing, shooting, skiing, snowboarding, wrestling • Alcohol banned for same reason
Creatine • Most popular nutritional supplement • In 2000, >$300 million in sales in the US
Creatine • Replenishes ATP in anaerobic exercise • Made in liver, kidneys, and pancreas • Dietary sources: meat, fish • Stored in skeletal muscle • Excreted as creatinine in urine
Creatine – disproven effects • Meta-analysis 2002: • NO overall benefit on anaerobic performance (weight lifting, sprint cycling, spring running, sprint swimming, kayaking, arm cranking, or jumping/kicking) • 29 quality studies • 35% were statistically significant between Cr and Placebo • 65% NON statistically significant