Transcript Ergogenic aids - Information Technology at La Trobe

Ergogenic aids
Today
• Exam
• Nutritional ergogenic aids
• Pharmacalogical ergogenic aids
Exam
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9/11/07
Afternoon
Check exam timetable
Must be done on this day
20 M/C- 1 mark each
8 short answer, 10 marks each
Ergogenic aids
• Substances and procedures believed to
improve
– physical work capacity
– Physiologic function
– Athletic performance
Ergogenic aids
• 1- stimulate CNS
• 2- increase storage or availability of a
limited substrate
• 3-Supplemental fuel source
• 4- reducing or neutralising performance
inhibiting metabolic by-products
• 5- facilitating recovery from strenuous
exercise
Nutritional Ergogenic Aids
Nutritional Ergogenic Aids
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Buffering solutions
Phosphate loading
Anti-cortisol−producing compounds
Glutamine
Phosphatidyl serine
Chromium
Creatine
Buffering solutions
• In exercise 30-120 seconds, anaerobic energy
transfer is used
• Significantly
– Increases lactate production
– decreases intracellular pH ( towards acidic)
• These decreases in pH
– inhibit energy transfer
– reduce ability of muscle fibres to contract
• Buffering solutions guard against acidosis
(decrease in pH)
Sodium bicarbonate
• Benefits athletes in events at near maximum
intensity for 1-7 minutes
• Acute loading (one time dose) – dosage =
300 mg per kg bodyweight
– increase total work (joules) from 9 - 27%
– increase peak power output (watts) by 5.3 - 8.7%
• Chronic loading - 500 mg/kg body mass in 4
doses every 3-4 hours for 5-6 days.
Benefits
40
39
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37
36
35
Cont rol
Acut e
Chronic
37. 16
38. 44
39. 21
36. 85
39. 36
Work (joules)
Acute v s Chronic Bicarb Loading
36. 60
39. 14
Side effects
• Nausea, bloating, vomiting, and diarrhea
• Most common when loading includes the
NaHCO3 water mixture.
• If athletes drink large quantities of water in
acute loading method, the gastrointestinal
distress is often reduced
• NaHCO3 gelatin capsules help to
effectively reduce or eliminate the
likelihood of gastrointestinal discomfort.
Another buffer- Phosphate loading
• Effectiveness not well supported
• Increasing intra and extra cellular
phosphate levels:
– Increases ATP phosphorylation
– Increases myocardial functional capacity 
increased aerobic performance
– Increased o2 extraction to muscle
Creatine
• Remember Cr was needed to bond to the spare
phosphate in the ATP-PC system
• Therefore Cr is critical in replenishing ATP and
for all out effort lasting up to 10 seconds
• Most popular ergogenic aid used among NCAA
college athletes (USA)
• Found in meat, fish and poultry
• Sold as a supplement in powder, tablet, capsule,
liquid (dosage = 6-30g)
• Not considered to be illegal PED
 Creatine
(Cr)
 CrP + ADP
 ATP +  Cr
 Anaerobic capacity
 rate of CrP resynthesis
 muscular power
 hydration
 lean body mass
Side effects of Creatine
• Increase in muscle swelling due to the
storage of more water around the muscles
 may increase the chances of injury,
especially between muscle and tendon
connections
• Nausea
• Cramping possibly due to water retention
• Dizziness if excessive quantities taken
• Diarrhoea
Young athletes and creatine
• 148 male college recreational resistance trainers
(USA) (Williams et al., 2004)
– 47.3 % reported creatine use and
– 74.3 % of the creatine users were also using protein
in an effort to increase muscle bulk
• LaBotz, & Smith, 1999 NCAA athletes
– 68% of athletes had heard of creatine and 28%
reported using it.
– 48% of men had used creatine, and 4% of women.
– all men's teams had at least 30% use
– 1/3 had first used it in high school
Sources of information
LaBotz & Smith, 1999
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Friends
Team mates
Trainers
Coach
• Over 80% of athletes using creatine said
that someone had specifically
recommended it to them
Anti-cortisol producing compounds
• Cortisol decreases amino acid transport to
cells which blunts anabolism
• Excessive amounts cortisol  protein
breakdown and muscle atrophy
• Glutamine and Phosphatidylserine (PS)
produce an anti-cortisol effect
Glutamine
• Most abundant naturally occurring, non-essential
amino acid in body
• Food sources of glutamine include meat, poultry,
fish, beans, eggs, and dairy products.
– 1) A substrate for DNA synthesis.
– 2) Major role in protein synthesis
– 3) Promotes muscle growth and decreases muscle
catabolism.
– 4) Precursor for rapidly dividing immune cells, thus
aiding in immune function.
– 5) Alternative source of fuel for the brain and helps to
block cortisol-induced protein catabolism.
Chromium
• Often sold as a “fat burner”
• Insulin takes glucose to storage.
• Chromium stimulates the activity of insulin,
aiding glucose and fat metabolism,
• Found in high concentrations in foods
such as meats, whole grains, cheese,
mushrooms, prunes, nuts, asparagus,
beer, and wine
• Benefits unclear
Ginseng
• Asian medicine
• Claims to build energy and
reduce stress
• Often $$$
• Anecdotal ergogenic effect
• No empirical evidence
Ephedrine
• Amphetamine like compound, from
the same source but weaker than
pseudoephedrine
• From ephedra plant
• Commonly used as a stimulant,
appetite suppressant, concentration
aid, decongestant
• Athlete deaths linked to use- heart
attacke, cardia arrythmia, stroke,
seizures
Green Tea
Oprah Winfrey Show
• “Oprah: Now I've read in your book that you said if
I just replaced coffee with green tea instead, that I
could lose 10 pounds in six weeks.
• Dr. Perricone: Absolutely.
• Oprah: Now really. How could that -- what is the
big deal about this?
• Dr Perricone: Coffee has organic acids that raise
your blood sugar, raise insulin. Insulin puts a lock
on body fat. When you switch over to green tea,
you get your caffeine, you're all set, but you will
drop your insulin levels and body fat will fall very
rapidly. So 10 pounds in six weeks, I will guarantee
it.
• Oprah: I'm gonna do that. OK. That is so good!
Whoo! That is great.”
Duloo et al 1999- Efficacy of a green tea extract rich in catechin
polyphenols and caffeine in increasing 24-h energy expenditure
and fat oxidation in humans
• Argued that increases in BMR by increase in
thermoegenesis leads to weight loss
• Thermogenesis contributes 8–10% of daily EE in
a typical sedentary man (760–950 kJ in our
subjects)
• 4% increase in 24-h EE (328 kJ) due to the
green tea extract would extrapolate to a 35–43%
increase in the thermogenesis compartment of
daily EE.
• 328 kj = 80 calories = 4/5 of a tim tam
Saper et al. 2004
• 50 individual dietary supplements and
more than 125 commercial combination
products are available for weight loss.
• Currently, no weight-loss supplements
meet criteria for recommended use.
Pharmacologic Aids to Performance
Pharmacologic Aids to
Performance
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Caffeine
Alcohol
Anabolic steroids
DHEA
Amphetamines
Caffeine
• Enhances endurance performance by
– Increasing time to fatigue
– Reducing perception of effort
– Mobilizing FFA
– Stimulating secretion of epinephrine
• May impair endurance performance by
– Stimulating diuresis leading to dehydration
• May improve sprint & power performances
CAFFEINE
Improved exercise
endurance
Stimulant to CNS
 Diuresis
 Lipolysis
 Incidence of
cardiac arrythmias
 Muscle glycogenolysis
Alcohol
• Provides 7 kCal per gram
• Ergogenic effects
– May reduce tension and anxiety
– Provides no known ergogenic effects on strength,
speed, power, or endurance performances
• Ergolytic effects
– Inhibits metabolism
– Suppresses ADH secretion, leading to diuresis
and dehydration
– Impairs balance, memory, visual perception,
speech, reaction time and motor coordination
Anabolic Steroids
• Synthetic derivatives
of testosterone
• Designed to maximize
anabolic effects
– Enhance protein
synthesis
– Inhibit protein
degradation
• Increase skeletal
muscle hypertrophy
and strength
Examples of Anabolic Steroids
Oral, patches, injectable
• Anavar
• Anadrol
• Dianabol
• Equipoise
• Testosterone
• Winstrol
• “the clear”- Marion
Jones
Associated Side Effects of
Anabolic Steroids
• Cardiovascular
– Increased LDL-C
– Decreased HDL-C
– Hypertension
• CNS
– Mood swings
– Violent behavior
– Depression
• Hepatic
– Decreased Liver
enzymes
– Jaundice
– Hepatic tumors
• Endocrine
– Altered glucose
tolerance
– Decreased FSH, LH
– Acne
Reproductive Side Effects
• Male
– Testicular atrophy
– Gynecomastia
– Impotence
– Enlarged prostate
– Male pattern
baldness
• Female
– Menstrual
dysfunction
– Altered libido
– Clitoral
enlargement
– Deepening voice
Side effects (Larance &
Degenhardt, 2007)
• 97% of users experienced a minor side effect,
such as increased appetite
• 10% experienced severe ones such as liver
damage
• 87% had some change in their mood and
behaviour
• And 27% experienced mental health concerns
• 95% exhibited at least one sign of dependance
Reasons for use
• Fuller and LaFountain (1987) - athletes
rationalise their use by trying to justify that
using steroids caused no harm either to
themselves or to others.
• Also, individuals perceived their
competitors were taking anabolic drugs, so
they needed to use to compete at the
same level.
Usage- university athletes
• Australia (NSW) = 0.3% of adults (>12 yrs)
– 12-17 yr olds 3.6%males and 2.2% female athletes
(Larance & Degenhardt, 2007)
• use ranges within each sport from
– 0% to 5% in males
– 0% to 1.5% in females, with an
– overall mean prevalence of 1.1%
(Green et al., 2001)
• These findings are believed to be
underestimates due to fears of legal or personal
consequences of using prohibited ergonomic
aids
DHEA
• Dehydroepiandrosterone
(DHEA)
• Relatively weak anabolic
steroid hormone, similar
to sex hormones
• Effects unclear
• Banned substance at
zero tolerance levels
• Produced naturally in the
body therefore difficult to
detect
Growth Hormone
• A peptide hormone
secreted by the anterior
pituitary gland
• Facilitates tissue-building
processes and normal
growth and development
• Enhances lipolysis and
elevates blood glucose
levels
Growth Hormone
• Combined with resistance training, GH
may facilitate skeletal muscle
hypertrophy and strength gains
• Also needs to be combined with
testosterone
• Chronic elevations in GH are associated
with acromegaly, hypertrophy of soft
tissue organs, diabetes, elevated blood
pressure, and atherosclerotic diseases
Amphetamines
 Stimulants to the CNS, but far
more potent than caffeine.
Mimic sympathetic hormones
epinepherine and
norepinepherine
Increase BP. HR, Cardiac
output
Breathing rate, metabolism,
blood glucose
 Effects last for 30-90 minutes
Amphetamines
• Increase risk for;
– Physical/emotional dependency & tolerance
– Headache, insomnia, nausea, dizziness,
– Inhibited pain reflexOver-exertion causing
musculoskeletal injury
– Cardiac arrhythmias, Hypertensive
responses to exercise
– Irritability, Paranoia
Physiological aids
Blood doping
Erythropoieten (EPO)
Red blood cell reinfusion (blood
doping)
• Practice of illicitly boosting the number of RBC in
order to enhance athletic performance.
• Increased RBC can carry more O2, which can
improve an athlete’s aerobic capacity and
endurance.
• Two types
– homologous transfusion- RBC from a compatible
donor are harvested, concentrated and then
transfused into the athlete’s circulation
– autologous transfusion- the athlete's own RBCs are
harvested well in advance of competition and then reintroduced before a critical event.
EPO
• Peptide hormone that occurs naturally in the body. EPO
is released from the kidneys to stimulate increased red
blood cell production in the bone marrow
(erythropoiesis).
• Increased RBC = increased amount of oxygen the blood
can carry to the body's muscles. may also increase the
body's capacity to buffer lactic acid.
• Recombinant (artificially produced) EPO has a
legitimate use in the treatment of anaemia in patients
with diseases such as kidney disease, HIV and some
cancers.
• Some athletes may use recombinant EPO to improve
endurance performance or to improve recovery from
anaerobic exercise.
Side effects
• Increase in blood viscosity  heart has to
work harder to pump the thicker blood and
the blood is more prone to clot.
• Increased risk of heart attack, stroke and
blood clots in the lung.
• The risk is exacerbated by dehydration
which often occurs during endurance
exercise.
How detected?
• Measure Hematocrit - the fraction
of blood cells by volume that are
RBCs.
• Normal HCT is 41-50% in adult
men and 36-44% in adult women
• New way- compare the levels of
mature and immature RBCs in an
athlete's circulation.
– If a high number of mature RBCs is
not accompanied by a high number of
immature RBCs it suggests that the
mature RBCs were artificially
introduced by transfusion.
Summary
• Good to be aware of all of these to dispel
myths/ talk kids out of using stuff
• Give correct information
• Be careful with medications
• Investigate fully