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Ergogenic aids

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Ergogenic aids

Today

• Exam

• Nutritional ergogenic aids

• Pharmacalogical ergogenic aids

Exam

• 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 AidsNutritional Ergogenic Aids

Nutritional Ergogenic AidsNutritional Ergogenic Aids

• 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

35

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Wo

rk (

jou

les

)

Acute vs Chronic Bicarb Loading

Control 37.16

Acute 38.44 36.85 36.60

Chronic 39.21 39.36 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

• 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 TeaOprah 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 PerformancePharmacologic Aids to Performance

Pharmacologic Aids to Performance

Pharmacologic Aids to Performance

• Caffeine

• Alcohol

• Anabolic steroids

• DHEA

• Amphetamines

CaffeineCaffeine

• 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

Improved exerciseendurance

Stimulant to CNS

Diuresis

Incidence of cardiac arrythmias

Muscle glycogenolysis

Lipolysis

CAFFEINE

AlcoholAlcohol

• 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 SteroidsAnabolic 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 SteroidsExamples of Anabolic Steroids

Oral, patches, injectable • Anavar• Anadrol• Dianabol• Equipoise• Testosterone• Winstrol• “the clear”- Marion

Jones

Associated Side Effects of Anabolic Steroids

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 EffectsReproductive 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 HormoneGrowth 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 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 reflexOver-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 re-introduced 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