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Ergogenic aids fall into two categories:
Physical / Verbal– cheering, music, altitude training, sauna
and massage, psychology etc.
Chemical and Pharmacological – anabolic steroids, stimulants, narcotic
analgesics, beta blockers, diuretics, amino acids, vitamins etc.
Ergogenic Aids: History of Use Ancient Greek Olympians ate mushrooms Aztec athletes ate human hearts In late 1800s, European cyclists took heroin, cocaine
"speedballs," and ether-soaked sugar tablets Winner of 1904 Olympic marathon took strychnine
and brandy during race Winner of 1920 Olympic 100-m dash drank sherry
with raw egg before race In 1960 Olympics, Danish cyclist died in road race
from amphetamine In 1967 Tour de France, famed British cyclist died,
also from amphetamine Olympic testing began in 1968 for stimulants
Ergogenic Aids: History of Use
Development of Dianabol East German female
swimmers of 1970s-1980s Cyclists deaths (1987-1990) Chinese female swimmers
(1992-1994) 1998 Tour de France
27 Chinese athletes removed from team
Bulgarian and Romanian weightlifting teams expelled
USATF relinquished drug testing– alleged >12 positive tests
not reported last 2 years
Desire to Win by Elite Athletes
>90% would take it if assured of not being caught
>50% would take it even if side effects were lethal in 5 years
A 1997 SI survey of elite US athletes asked whether they would take an illegal drug that
guaranteed an Olympic gold medal.
Anabolic Steroids
Male hormones have anabolic effects– accelerated growth of muscle, bone, and
red blood cells
Anabolic steroids are synthetic relatives to testosterone– high-volume training needed for beneficial
effects– inhibit protein breakdown
Anabolic Steroids: Secondary Effects
Androgenic effects– males: testicular atrophy, breast
development, sperm count, acne– females: masculinization, facial & chest
hair growth, deepening of voice, acne
Additional effects– aggressiveness, mood swings, altered
glucose metabolism, thyroid, lipid profiles
Protein Supplementation
Research suggests that athletes have 2-3X RDA higher protein needs
Typical American athletes already consume this amount
Increased carbohydrate intake more important to increasing muscle mass
Fatigue: Implications for Ergogenic Aids
Power/Speed events– muscle mass– CNS & sympathetic stimulation– acidosis– depletion of PCr
Endurance events– muscle glycogen depletion– low blood [glucose]– fat oxidation rate– dehydration– diminished O2 delivery
Bicarbonate Loading
Intramuscular effects of acidosis PFK, phosphorylase Ca2+ sensitivity cross-bridge force output ATP turnover– slows recovery rate
Effects of bicarbonate loading plasma pH– speeds H+ and La- transport from muscle
Benefits of Bicarbonate Loading
not all studies report performance benefits– dependent on dosing– benefits maximal exercise of 1-10 min– GI distress
Endurance Training Adaptations
VO2max (~15%)
cardiac output (~15%) mitochondrial volume (2X) La threshold shifted to right ability to use fats (spares glycogen)
Increasing O2 Delivery blood doping
RBC and blood volume submax pH– La, HR
breathing 100% O2
EPO– stimulates RBC production
altitude training– live high, train low
ACSM Position Stand, The use of blood doping as an ergogenic aid. MSSE, 28:i-viii, 1996.
What limits endurance performance?
Pyruvate-malate
oxidase
Palmitoyl carnitine oxidase
VO2max Maximal endurance
Cytochrome oxidase
.95 .93 .74 .92
Pyrave-malate oxidase
.89 .68 .89
Palmitoyl carnitine oxidase
.71 .91
VO2max .70
Davies et al., 1981, 1982
What limits endurance performance?
Recovery in rats restored to normal iron-intake diet.
Davies et al., AJP, 1982
Increasing Energy Supply
Carbohydrate availability– feeding before/during
competition– enhancing fat use
Creatine– important for energy
production during power/speed events
Glucose
Increasing Fat Utilization
FA availability will fat oxidation Caffeine
lipolysis? EPI release?– blocks adenosine receptors– inhibits phosphodiesterase
Ephedrine– ß-receptor agonist
Increasing Fat Availability
Caffeine fat availability and carbohydrate use?– spares carbohydrate stores? threshold for motor unit recruitment– altered E-C coupling– facilitated nerve transmission ion transport w/in muscle catecholamine release
Other nutritional products
Effect of Diet on Carbohydrate Storage and Exercise Duration
CHO intake Glycogen content
Exercise time
(g/24 h) (mmol/kg) (min)
100 (15%) 53 57 280 (55%) 100 114 500 (98%) 205 167
Other Banned Substances Stimulants – reduces tiredness
– ephedrine, cocaine, amphetamines
Painkillers– narcotics
Diuretics– rapid weight loss– masks steroid use