Download Ergogenic aids handouts

Lab submission
Ergogenic aids
• Labs due week 13
• Lab groups 1, 2,
– Hand in after Monday’s lecture (11-12) to my
office (ed. 3.11)
Æ pick up before 4 pm Monday
• Lab groups 3, 4, 5
– Hand in to my office wednesday 9am-10 am
ÆPick up before 4 pm Wednesday
Exam
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Monday 3rd November
Morning 9am
Check exam timetable
Must be done on this day
40 M/C- ½ mark each
8 medium 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
Pharmacologic Aids to Performance
Caffeine
Amphetamines
Alcohol
1
Caffeine
• Enhances endurance performance by
– Increased alertness
– Increasing time to fatigue
– Reducing perception of effort
– Mobilizes FFAÆ spares glycogen
– Stimulating secretion of epinephrine
– Decreased reaction time
• May improve sprint & power performances
Caffeine- Side effects
• May impair endurance performance by
– Stimulating diuresis leading to dehydration
– Nervousness
– Restlessness
– Insomnia
– Headache
– Gastrointestinal problems
– Tremours
Amphetamines
ÌSpeed, ephedrine,
pseudoephedrine
ÌStimulants to the CNS, but far more potent than
caffeine.
ÌMimic sympathetic hormones epinepherine and
norepinepherine
-Increase BP. HR, Cardiac output
-Breathing rate, metabolism, blood glucose
Alcohol
Amphetamines- Side effects
• Increase risk for;
– Physical/emotional dependency & tolerance
– Headache, insomnia, nausea, dizziness,
– Inhibited pain reflexÆOver-exertion causing
musculoskeletal injury
– Cardiac arrhythmias, Hypertensive
responses to exercise
– Irritability, Paranoia
• 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
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Androgenic-Anabolic Steroids
Hormonal
Anabolic steroids
Human growth Hormone
• 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
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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
Human Growth Hormone
• A peptide hormone
secreted by the anterior
pituitary gland
• Facilitates tissue-building
processes and normal
growth and development
– Enhanced muscle and
bone growth
• Enhances lipolysis
(releases FFA’s) and
elevates blood glucose
levels
• Healing after
musculoskeletal injuries
Growth Hormone
• Combined with resistance training, GH
may facilitate skeletal muscle
hypertrophy and strength gains
– Or just fluid retention
• Also needs to be combined with
testosterone
• May be associated with age
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Side effects
Chronic elevations in GH are associated
with
• acromegaly,
• hypertrophy of soft tissue organs,
• diabetes,
• elevated blood pressure, and
• atherosclerotic diseases
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
– autologous transfusion
Side effects
• Increase in blood viscosity Æ 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.
• Differing individual responses to EPO
Physiological aids
Blood doping
Erythropoieten (EPO)
Bicarbonate loading
Phosphate loading
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).
– improve endurance performance (Increased Vo2
max)
– improved recovery from anaerobic 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.
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Buffering solutions
Sodium bicarbonate
• In exercise 30-120 seconds, anaerobic energy
transfer is used
• Significantly
– Increases lactate production
– decreases intracellular pH (Æ towards acidic)
• These decreases in pH
– inhibit energy transfer
– reduce ability of muscle fibres to contract
• Buffering solutions guard against acidosis
(decrease in pH)
– 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.
Side effects
Acute vs Chronic Bicarb Loading
• 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.
37.16
38.44
39.21
36.85
39.36
Work (joules)
Benefits
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Control
Acute
Chronic
• Benefits athletes in events at near maximum
intensity for 1-7 minutes
• Acute loading (one time dose) – dosage =
300 mg per kg bodyweight
36.60
39.14
Another buffer- Phosphate loading
• Increasing intra and extra cellular
phosphate levels:
– Facilitates release of oxygen from RBC to
muscles
– Increases ATP phosphorylation
– Increases myocardial functional capacity Æ
increased aerobic performance
Nutritional Ergogenic Aids
Creatine
Weight loss
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Creatine
How does it work?
• 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 illegal
• Buffer- maintains acid base balance
More ATP Æ
• Enhanced use of ATP-PC systemÆ increased
peak power
– 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
• Facilitates recovery as ATP not fully depleted
↑ 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 Æ 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
• Kidney problems
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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
Supplements claiming to
assist weight loss
• Over 80% of athletes using creatine said
that someone had specifically
recommended it to them
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
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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.
Performance Enhancing Genetics
• Gene doping
• Manipulate DNA to improve speed, power
or performance
– In Vivo- viruses modified to deliver artificial
gene to target tissue/organ
– Ex Vivo- gene transfer to cells occurs outside
the body and is then implanted into the
recipient
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
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