Performance-Enhancing
Substances
Effects,
Risks, and Appropriate Alternatives
Ergogenic
Aids
§ Definition
Substances
that are reputed to enhance performance
§ Types
1.
Naturally occurring hormones and drugs that mimic their effect
2.
Dietary supplements
Ergogenic
Aids
§ Classification
Drug (highly
regulated)
§ A substance
which changes body structure or function.
§ Stimulate
hormone secretions
§ Looks like
medicine and/or is administered differently than foods
Dietary
Supplement (not highly regulated)
§ Highly
refined products
§ No positive
nutritional value
Ergogenic
Aids
§ Basis of Dietary Supplements
Supplements diet or contains one or
more of the following ingredients:
§ Vitamin
§ Mineral
§ Herb or botanical
§ Amino acid
§ Substance that adds to dietary intake
§ A metabolite or extract of above substances
Supplements must be intended for
ingestion and cannot be advertised for use as a conventional food or sole item
in diet
Ergogenic
Aids
§ Currently banned substances by IOC
Psychomotor stimulants
§ Amphetamines, cocaine, methylphenidate
Sympathomimetic amines
§ Ephedrine, isoprenaline
Other stimulants
§ Caffeine (above certain levels), doxapram, strychnine
Anabolic steroids
Other hormones
§ Growth hormone, erythropoietin
Narcotic analgesics
§ Codeine, heroin, morphine
Masking agents and diuretics
Naturally
Occurring Hormones
Anabolic
Steroids
§ Definition
Natural or
synthetic derivatives of testosterone that are responsible for the
masculinizing and muscle-building responses in the body.
Anabolic
Steroids
§ Types of Anabolic Steroids
Orally active
§ Medically used for maintaining secondary sexual characteristics- dose of
15mg/day
§ Athletes may use dosages of 300mg/day
§ Examples: Dianabol, Anavar, Anadrol
Injectables
§ Clinically used for rare diseases and men with low sperm counts -typical
dosage of 250mg/wk for up to 6 months
§ Athletes may use dosages of
1,000mg or more per wk
§ Some injectables stay in body for 1.5 days and others up to 3 months from
single injection
Anabolic
Steroids
§ Effects:
Increase lean body mass in both men
and women
Increase water retention
No substantial proof that anaerobic
performance is improved
No proven benefit to aerobic athletes
Increased aggressiveness
Health risks including abnormal
cholesterol profiles, liver tumors, temporary infertility, and increased skin
problems (e.g. acne)
Human
Chorionic Gonadotropin
§ Obtained
from urine of pregnant women
§ Increases
testicular testosterone production; may later lead to desensitization in testes
§ May stimulate
estrogen production leading to development of female characteristics
§ Used by some
to reduce body fat
Erythropoietin
(Epo)
§ A naturally produced protein hormone by the kidneys
§ Stimulates production of red blood cells
§ Increases in response to endurance exercise
§ Administration of recombinant Epo results in:
Increase in hematocrit (# of rbcs)
Increase in hemoglobin
Increase in aerobic performance
Risk of blood thickening, ↑systolic
b.p., ↑heart problems potentially leading to heart failure
Beta-adrenergic
Agonists
§ Chemical substances related to epinephrine
§ Effects:
Used to treat asthma and other
life-threatening medical conditions
Increase in lean body mass
Decrease in stored fat
§ Taken by athletes in dosages of 20-60ug/day in 2-week cycles (avoid
desensitization resulting in ineffectiveness)
§ Side effects not well established, however:
May lead to sleeplessness,
nervousness, and increased heart rate
Drug
Testing
§ Effective programs are year-round, random, and unannounced
§ Tests have been readily developed to identify unnatural substances; more
difficult to identify natural substance abuses-usually look for high levels
§ Athletes often use masking agents, such as diuretics to avoid detection
Used to dilute urine sample
Can be detected more easily today
Dietary
Supplements
§ Not found to
be effective in improving sport performance
§ Claims of
benefits for improvement of sport performance are unfounded at this point
Dietary
Supplements
§ Vitamins
Not found to be sport enhancers
Vitamins C and E are considered as
anti-oxidants which may help reduce tissue damage from exercise
§ One study suggested reduction of altitude stress and improvement in time
to exhaustion with Vitamin E supplementation
§ Other studies have suggested a decrease in DOMS (delayed-onset muscle
soreness)
Supplementation could lead to toxic
conditions or simply waste of money
Dietary
Supplements
§ Steroid Replacers
Substances which are considered to be
precursors to steroids such as cholesterol
§ Thought process:
If cholesterol products are added to diet, more anabolic steroids will be
produced
§ Examples:
- pure butter
- androstenedione
used by Mark McGwire
*
cholesterol → gandroh →
testosterone
- sapogenins plant
producers of steroids
- boron claims to ↑
testoterone but not true
Dietary
Supplements
§ Growth
Hormone Releasers
Amino acids
that prompt an increase in growth hormone levels in the body
§ Examples:
Arginine
Ornithine
Gamma-hydroxybutyrate
(GHB)
§ Very
dangerous substance leading to coma and seizures
Dietary
Supplements
§ L-Carnitine
Essential for transport of free fatty
acids into mitochondria
Found primarily in heart &
skeletal muscle
As supplement, difficult to absorb
§ Not proven
to be effective in sport performance
May provide benefit of keep growth
hormone in system longer by the increased availability of binding proteins in
the blood (from article discussed in class)
Dietary
Supplements
§ Creatine
With
supplementation, concentrations are higher in the muscle
Shown to
enhance performance by 5-7% in short-duration, high intensity events
ATP levels
are more readily maintained and not depleted as quickly with muscle contraction
Dietary
Supplements
§ Creatine
Faster recoveries from intense
exercise have been shown
If taken as creatine monohydrate in
dosage of 20g/day, high levels of creatine can be maintained in muscle for
several weeks
CHO intake can improve muscle
creatine uptake
Short term risks seem to be minimal
except for digestive system disturbances, and other related symptoms
Dietary
Supplements
§ Caffeine & other Stimulants
Potential benefits:
§ Delay fatigue
§ Increase alertness
§ Produce euphoric sense
Caffeine (1 c of coffee contains ~
120mg)
§ More than 3 cups of coffee prior to competition would probably exceed
limit of 12ug/ml (set by IOC)
§ Less than 3 cups can benefit endurance performance
Due to its ability to increase availability of fatty acids
§ Potential problem → diuresis leading to dehydration
Summary
§ Most
ergogenic aids that might enhance performance are banned
§ Dietary
supplements are not effective in most athletic performances
§ Many
ergogenic aids have health risks