Buffering solutions In exercise 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 % –increase peak power output (watts) by % Chronic loading 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 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 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 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 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.
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
Improved exercise endurance Stimulant to CNS Diuresis Incidence of cardiac arrythmias Muscle glycogenolysis Lipolysis CAFFEINE
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
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 minutes
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