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Sports Supplements. Andrew Gregory, MD Assistant Professor, Orthopedics/ Pediatrics Team Physician, Vanderbilt University Jan. 10, 2002. Definition: Ergogenic Aids. Ergo = work Gennan = to produce Any substance or method used to enhance performance through increased energy utilization:
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Sports Supplements Andrew Gregory, MD Assistant Professor, Orthopedics/ Pediatrics Team Physician, Vanderbilt University Jan. 10, 2002
Definition: Ergogenic Aids • Ergo = work • Gennan = to produce • Any substance or method used to enhance performance through increased energy utilization: • production • control • efficiency
Drugs: Hormones Stimulants Narcotics Diuretics B-Blockers Supplements: Prohormones? Amino Acids Metals Antioxidants Herbs Classification
Prevalence: • Estimated 11% of HS athletes, college, and professional. • Majority of Olympic swimmers, cyclists, sprinters, & weight lifters • 2/3 of the 1998 Tour de France teams • Billion Dollar Industry
Reasons: • Have to use them to be competitive • Need the edge • Not genetically gifted • Dissatisfaction with size/ weight • Peer/ Team Pressure
Hormones • HGH • EPO • BHCG • Steroids
Human Growth Hormone • Normally secreted by the pituitary • Normal function of GH is growth and development of every body system, including bone and muscle • Can be stimulated by propanolol, vasopressin, clonidine, and levodopa • Synthetic growth hormone
Side Effects: • Acromegaly (may be irreversible) • Peripheral Neuropathy • Coronary Artery Disease • Cardiomyopathy • Diabetes, Hypothyroidism, arthritis • No available urine test available, but banned by NCAA and IOC
Erythropoietin • Hormone released by the kidneys in response to low Hct • Stimulates RBC production from bone marrow • Has recently been manufactured by recombinant DNA technique • Can increase Hct in renal patients by up to 35%, lasting up to 7 months • Used most by cyclists
Blood Doping • Induced Erythrocythemia: An increase in Hb following reinfusion of an athlete’s blood • Goal: to increase the oxygen-carrying capacity of Hb • Has been used as far back as 1947 • 1984: seven US Olympic cyclists guilty • Banned by IOC in 1985
Pathophysiology • Muscles depend on ATP for energy • Aerobic metabolism = breakdown of glycogen in presence of O2 >>>ATP • Aerobic metabolism-higher yield of ATP • More O2 carrying capacity>>more ATP production, more energy to muscle • 1 U PRBC>>500 ml / min increase in O2 carrying capacity
Methods: • Autologous reinfusion method: 2 units blood removed 4-8 weeks prior to competition & frozen c glycerol • Hb / Hct returns to pre-transfusion levels • Reinfusion 1-7 days prior to event • Can produce up to 25% improvement in endurance, with poorer conditioned athletes showing greatest benefits
Side Effects: • Heterologous blood: transfusion rxn (3-10%), Hepatitis (10%), HIV (?%) • Autologous blood: bacterial infections • Polycythemia: increased viscosity >>CHF, HTN, CVA • Most young healthy athletes show no side effects
Detection: • Blood doping and Erythropoietin: banned by IOC • No known urine test to detect • Testing: Measured Hct >50 • Measurement of serum Fe and Bilirubin to detect hemolysis after frozen PRBC transfusion
Anabolic Steroids • The ultimate ergogenic aid aka “Juice” • Creates the Superhuman Athlete • Testosterone derivatives (cholesterol) • Produced in the adrenal/ testes
Anabolic/Androgenic Steroids • Anabolism - Constructive • Catabolism - Destructive • Anabolic effects : inc. skeletal mm mass • anticatabolism • Androgenic effects: secondary sexual characteristics - pubic hair, genital size • No Pure Anabolic Steroids
History of Steroids • First Available - 50’s (Dianabol) • Drug Banned - 60’s • Testing Initiated- ‘76 • Athletes Banned - ‘83 Pan Am Games • Schedule III Controlled Substance - ‘90 Anabolic Steroid Control Act • US Dietary Supplement Act - ‘94 no FDA approval if no “drug intent”
Administration: • Athletes may take up to 40-100x therapeutic dose (200-2000 mg/ wk) • IM adm bypasses the liver/ PO does not • “Stacking”: using various aids in combination • “Cycling” : gradual inc. then taper over 6-10 weeks, 1-3 cycles /year, “bridging” between • Illicit - Nandrolone, Stanozolol (Winstrol), Methelone, Tibolone, Oxandrolone • Medical - Testosterone, Enanthate, Undelanoate, Dehydrotestosterone (patch)
Desired Effects: • Increase in strength • Increase in weight • Increase in aggressiveness • Increased capability of sustaining repetitive, high intensity workouts • Enhanced performance
Side Effects: • CV: MI - hypertension, inc. LDL, dec. HDL, cardiac hypertrophy, thrombosis • Endocrine: virilization, testis atrophy, azospermia, priapism, prostatic hypertrophy/ CA, gynecomastia, erectile dysfct, libido • Liver : peliosis hepatitis, hyperplasia, adenoma, no carcinoma, elevated LFTs • MS: epiphyseal closure, inc. bone density, dec. tendon strength
Side Effects (cont’d): • Skin: acne, hirsuitism, striae, androgenic alopecia, inc. sebaceous glands • Metabolic: hypernatremia, kalemia, phosphatemia, calcemia, “prediabetic” • Psychiatric : aggressiveness, extreme mood swings - depression/ mania, dependence, other drug use, “Reverse Anorexia” • Long Term - dec. life span
Specific Side Effects • Women (Virilzation): • Clitoril enlargement, Deepening of voice, Male pattern baldness, dec. breast size, libido • Children: • premature closure of growth plate in long bones & thus short stature
“Prohormones” • Androstenedione • DHEA • Androstenediol • Norandrostenedione • Norandrostendiol
Androstenedione • 1/2 of the “ Mark McGuire Special” • A natural steroid hormone found in all animals and some plants • Metabolite of DHEA • Precursor of testosterone • Synthesized in Adrenals/ Gonads • Metabolized in the liver to testosterone
Effects: • Benefits: Same as Testosterone • Increased energy • Enhanced recovery and growth from exercise • heightened sexual arousal and function • greater sense of well-being • Plasma levels of testosterone increased from 140% to 330% of normal levels after 50mg and 100mg doses • SE’s : Same as Testosterone • Banned by IOC, NCAA, NFL
DHEA (Dehydroepiandrosterone) • What it is: A hormone produced by adrenal gland • Claims: Anabolic effect • What is does: Increases testosterone levels • Banned by the NCAA, NFL
Stimulants • Caffeine • Amphetamines • Cocaine • Ephedrine
Amphetamines • Have been used as far back as WWII when soldiers used them to delay fatigue • First study in 1959 showed significant improvement in performance • Available data suggest Amphetamines can improve performance in sports where speed, power and endurance are required
Side Effects: • Related to drugs’ effect on CNS: insomnia, instability, agitation and restlessness • Confusion, paranoia, hallucinations • Dyskinesias, especially in facial muscles • Cardiac complications: HTN, arrhythmias • GI disturbances • Severe rebound of fatigue and depression after discontinuance
Caffeine • A Methylxanthine: same class as theophylline and theobromine • Exerts its’ effects by: • Translocation of Calcium for more muscular availability • Increase in cAMP by inhibition of phosphodiesterase • Blockage of adenosine receptors, blocking the sedative properties of adenosine
Caffeine (cont’d) • Is banned by IOC and NCAA in large doses • Legal limit = 15 micrograms / ml • Equal to 6-8 cups of coffee at one sitting, with testing within 2-3 hours • Beneficial most in endurance events, such as cycling • Doses up to 5 mg / kg were required to see benefits. Doses of 17 mg/kg produce the maximum legal limit.
Side Effects: • Similar to s/e of other stimulants: • insomnia, irritability, nervousness • Tachcardia, arrthymias, and possibly death!
Ephedrine • What it is: Is a drug found in herbal products containing Ma haung, anti-asthmatic medications, and many cold and cough products. • Claims: Increases body fat loss • What really does: Acts as a CNS stimulant, delays fatigue by sparing body glycogen reserves. Increase in B/p respiratory, heart rate, insomnia, and nervousness • Max dose : 24 milligams per day!!!!!!
Amino Acids • Creatine • L-Carnitine • Choline • Inosine • HMB (B-OH-B-Methylbutyrate)
Amino Acids • Essential amino acids: found in a balanced diet • Recommended protein intake: 0.8 g /kg/day • Athletes may benefit from up to 1.4 -2.4 g/kg/day • Most beneficial for athletes on a poor diet, or vegetarians • In endurance athletes, up to 10% of energy expenditure is from protein breakdown
Creatine • The Other 1/2 of the “Mark Mcguire Special” - The Creatine Craze - Sales expected to reach $200 million in 1998 • Use has spread: • 13% of HS athletes • 80% of University of Nebraska football team • 50% of NFL players • Vast majority of Olympic sprinters, cyclists, and sprinters
Creatine • Methylguanidine-acetic acid - made from glycine, arginine & methionine • Estimated Daily requirement: 2gms • Available in meats and fish (1/2 EDR) • Sold as Creatine Monohydrate • Stored in Skeletal MM • 2000 NCAA banned distribution in training rooms
Pathophysiology: • Energy Substrate for muscle contraction • Creatine binds Phosphorus as substrate for formation of ATP (main source of energy of contraction) • PCr also buffers Lactic Acid • After PCr is depleted must resort to glycolysis for ATP production • Net result: sustained muscular contraction, delayed fatigue
Benefits: • Improved performance in repeated bouts of high intensity strength work and sprints • Single sprint activity results are equivocal • Does not enhance endurance exercise • More work with less lactic acid production • No studies on competetion benefits • 1998 ACSM meeting: 19/19 studies showed significant ergogenic benefit
Dosing: • Loading Phase: 20-30 gm/d, x 5 -7 days • Maintenance phase: 2-5 gm/day • Loading increases PCr stores by 10-40% • Normal resting levels of creatine: 100-150 mM/kg • Most striking benefits occur in subjects with lower resting Cr level • After saturation of tissues, excessive supplementation is renally excreted
Side Effects: • Muscle Cramping • Diarrhea • Dizziness • Dehydration • Biggest danger: getting “impure” creatine • Significant WEIGHT GAIN common 2nd to water retention
The Perfect Supplement? • “The secret is to find something that is effective in improving performance, but not against the rules, and with no side effects” • “…no clear evidence of harmful side effects of creatine use has emerged…”--The Physician and Sportsmedicine, June 1998 • Long term effects of Creatine not yet studied: Concerns focus on effects to kidney, pancreas, and liver.
Counseling your patients • Creatine may or may not improve performance • Weight gain will occur • Side effects (especially long-term) not well known • Need to have renal and liver fct. Monitored • should not be used in patients with chronic kidney/ liver disease • Do not exceed the recommended dose
L-Carnitine • Synthesized in Liver/ Kidney from Lysine & Methionine • found in meats & dairy products • Assists in Fat transportation into muscle mitochondria for oxidation, sparing Glycogen & may prevent lactic acid accumulation • Improved endurance performance not shown in studies