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Ergogenic aids. Lab submission. Labs due week 13 Lab groups 1, 2, Hand in after Monday’s lecture (11-12) to my office (ed. 3.11) pick up before 4 pm Monday Lab groups 3, 4, 5 Hand in to my office wednesday 9am-10 am Pick up before 4 pm Wednesday. Exam. Monday 3 rd November
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Lab submission • Labs due week 13 • Lab groups 1, 2, • Hand in after Monday’s lecture (11-12) to my office (ed. 3.11) pick up before 4 pm Monday • Lab groups 3, 4, 5 • Hand in to my office wednesday 9am-10 am • Pick up before 4 pm Wednesday
Exam • 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
Caffeine • Enhances endurance performance by • Increased alertness • Increasing time to fatigue • Reducing perception of effort • Mobilizes FFA 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 • Speed, ephedrine, pseudoephedrine • 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
Amphetamines- Side effects • 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
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
Hormonal Anabolic steroids Human growth Hormone
Androgenic-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
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 Associated Side Effects of Anabolic Steroids
Male Testicular atrophy Gynecomastia Impotence Enlarged prostate Male pattern baldness Female Menstrual dysfunction Altered libido Clitoral enlargement Deepening voice Reproductive Side Effects
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
Side effects Chronic elevations in GH are associated with • acromegaly, • hypertrophy of soft tissue organs, • diabetes, • elevated blood pressure, and • atherosclerotic diseases
Physiological aids Blood doping Erythropoieten (EPO) Bicarbonate loading Phosphate loading
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
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.
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. • Differing individual responses to EPO
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.
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.
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 • Increasing intra and extra cellular phosphate levels: • Facilitates release of oxygen from RBC to muscles • Increases ATP phosphorylation • Increases myocardial functional capacity increased aerobic performance
Nutritional Ergogenic Aids Creatine Weight loss
Creatine • 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
How does it work? • Buffer- maintains acid base balance More ATP • Enhanced use of ATP-PC system 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
CrP + ADP ATP + Cr Creatine (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 • Kidney problems
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
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.