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 rbc’s)
–
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