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Ergogenic Aids

Ergogenic Aids. Nutritional Supplements for Athletes Liv Engelsen, MS. Outline. Regulation of nutritional supplements In-depth review of 5 popular ergogenic aids Caffeine Creatine Monohydrate Sodium Bicarbonate β – Alanine HMB

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Ergogenic Aids

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  1. Ergogenic Aids Nutritional Supplements for Athletes Liv Engelsen, MS

  2. Outline • Regulation of nutritional supplements • In-depth review of 5 popular ergogenic aids • Caffeine • Creatine Monohydrate • Sodium Bicarbonate • β – Alanine • HMB • Overview of research to support/refute additional supplements/practices • The best recovery beverage of all time… • Summary/Conclusion

  3. Definition Substances, devices or practices that enhance an athlete’s energy use, production or recovery

  4. Regulation Regulated by the Dietary Supplement Health and Education Act of 1994 (DSHEA) http://www.youtube.com/watch?v=3vxrTMYXpZo

  5. Caffeine • Most popular social drug in the US • Average adult ingests 3 mg/kg of caffeine daily • Alkaloid stimulant found in coffee, tea, colas, sports drinks, chocolate, etc. • Has been studied for its ergogenic effects for ~100 years • Levels of caffeine in foods vary greatly depending on preparation • Coffee: 60-150 mg/cup • Tea: 40-60 mg/cup • Cola: 40-50 mg/cup • Chocolate (1.5 oz): 20 mg dark/9 mg milk • Ergogenic effectiveness varies, depending on: • Age • Gender • Body size • Caffeine tolerance • Habituation • Cessation patterns

  6. Mechanisms of Action • Global effects on the CNS • Caffeine is a competetive, nonselective adenosine receptor antagonist • Leads to delayed fatigue, increased mental alertness, mood improvement, energetic arousal • Enhances concentration, visual acuity, reaction time and self-reported fatigue • Effects on hormonal, metabolic, muscular, cardiovascular, pulmonary and renal functions during rest and exercise. • Leads to decreases in respiratory exchange ratio (RER), peripheral fatigue, rating of perceived exertion (RPE), and threshold for exercise-induced cortisol and B-endorphin release • Leads to increases in oxygen uptake, cardiac output, ventilation, circulating levels of epinephrine, metabolic rate, and fat oxidation during endurance exercise in trained and untrained individuals • Bottom Line: The mechanisms by which caffeine improves athletic performance is multifactorialand extends well beyond any one biologic mechanism!

  7. Effects on Body Systems & Sports Performance

  8. Tolerance • Diminished responsiveness resulting from repeated exposure • Caffeine tolerance has been associated with increased adenosine receptor activity and a decrease in β-adrenergic activity • Lower caffeine doses are well tolerated by nonusers • Complete tolerance can occur in 5-6 days of moderate caffeine intake • Effective strategy for a nonuser: 3-4 days of consecutive caffeine use to aid intense workout sessions • Begin with 1-2 mg/kg and increase progressively over the next few days

  9. Psychological Factors

  10. Withdrawal • Withdrawal symptoms peak in 28 to 48 hours • Takes an average of 4 to 7 days to return to baseline • Main symptom is frequent and severe headaches • 2/2 vasodilation of cerebral blood vessels • Resumed or acute caffeine intake almost entirely reverses withdrawal symptoms, including headache • Regular caffeine users can optimize benefits by cutting back, but must be careful to avoid withdrawal symptoms • Reduce caffeine intake gradually at least 1 wk before competition • Resuming caffeine on the day of competition will again provide the desired ergogenic effects, as it would for a nonuser

  11. Intake Strategy • Caffeine reaches a peak plasma level between 30 and 75 minutes of ingestion • Half-life is 4 to 5 hours with modest intake, but longer when dose exceeds 300 mg • In 6 to 7 hours, 75% of caffeine is cleared from the body because it is rapidly absorbed and metabolized by the liver • Intake strategy is crucial for those seeking to improve athletic performance through caffeine use

  12. Dosing • As little as 1 mg/kg to as much as 13 mg/kg had positive effects on time to fatigue in endurance events, sports, and sprint or power events. • 1 to 7 cups of coffee • 3 to 18 cups of tea or soda • Some studies have found better ergogenic effect with lower dose (3-6 mg/kg) than higher doses • No evidence of greaterergogenic effects with more than 9 mg/kg • Higher caffeine intake may blunt cognitive performance • Gender differences • Men tolerate higher doses than women

  13. Safety Concerns • The common belief that caffeine leads to dehydration and causes poor athletic performance is a misconception! • Claims of adverse effects of caffeine on the cardiovascular system are inconclusive. • The high levels of antioxidants found in coffee and tea have been linked to a number of health benefits • Protection against heart disease and type II DM

  14. Research

  15. Think Fast! What has the highest caffeine content? Brewed tea Shot of espresso Brewed coffee Dark chocolate bar

  16. Creatine Monohydrate • An amine found naturally in some foods, particularly meat products. • Can be formed in the kidney and liver from glycine and arginine • Delivered to the muscle and combined with phosphate to create phosphocreatine: a high-energy phosphagen in the ATP-PCr energy system. • ATP-PCr energy system is important for rapid energy production, such as in speed and power events • Supplements come in various forms; powders, pills, candy, gels, etc. • Marketed to both strength and endurance athletes • Appears most effective for activities that involve repeated short bouts of high-intensity physical activity

  17. Ergogenic Benefits • Recent studies have shown significant improvements in: • Total and maximal force in repetitive isometric muscle contractions • Muscular strength and endurance in isotonic strength tests • Muscular force/torque and endurance in isokinetic strength testing • Cycle ergometer performance in maximal tests ranging from 6 to 30 seconds • Field performance tests such as jumping, running, swimming, and skating. • Less consistent, but overall favorable

  18. Exogenous Sources • Average adult needs to replace ~2 grams of creatine/day for maintenance of normal creatine and PCr levels. • Daily creatine intake of carnivores is ~1 g/day • Daily intake may be nearly zero for vegetarians • Endogenous creatine formation helps complement dietary sources to achieve 2 grams • Excessive amounts of exogenous creatine will not be stored, but will be excreted unchanged in the urine

  19. Proposed Mechanisms • Most of the creatine in the body is stored in the muscles • Research suggests that performance benefits are related to increased creatine within type II muscle fibers • 60% of total muscle creatine is PCr, and 40% is free creatine • Increasing the amount of PCr will provide more substrate for generating ATP during high-intensity exercise, and higher levels of free creatine will help re-synthesize PCr. • Alternative theory: creatine supplementation and anabolic hormones?

  20. Creatine Dosing • Very effective quick strategy • 20-30 g/day (5-7 g per dose over the course of the day) • Significant effects seen after only 2 days • Long-term supplementation at lower dose is just as effective • 4-5 g/day • Significant effects seen after 6 days • Once loaded, ~2 g/day for maintenance • Creatine supplementation appears safe when the recommended loading and maintenance doses are followed

  21. Special Considerations • Research suggests people may be responders or non-responders • Characteristics of nonresponers include : • Higher initial levels of creatine and PCr • Fewer type II muscle fibers • Individuals with initially low levels of intramuscular creatine are more responsive to supplementation • Vegetarians • Caffeine counteracts the ergogenic action of muscle creatine loading! • Vandenberghe et al., 1996 • Effect on body mass • >50 studies have shown an increase in body mass during the first week of creatine supplementation • Increased creatine in the muscle draws water • Formulation- creatinemonohydrate • Theoretically, dehydration, muscle cramps and heatstroke can occur • Drink plenty of water!!!!!

  22. Creatine supplementation enhances muscular performance during high-intensity resistance exercise Volek et al., 1997

  23. Think Fast! For maintenance of normal creatine and PCr levels, the average adult needs to replace ___ of creatine/day 1 g 2 g 3 g 4 g

  24. Sodium Bicarbonate • Alkaline (buffer) salt found naturally in the body that helps control pH and avoid excess acidity • Increases pH • Decreases H and lactate ions • During high intensity anaerobic exercise, energy needs are mainly provided by anaerobic glycolysis • This is associated with a high level of lactic acid production • Accumulation of excess lactic acid in the muscle cell interferes with the optimal functioning of various enzymes, resulting in fatigue • Increased perception of effort and decreased force production • Marketed to athletes as part of a sports supplement • Not as popular as some of the other ergogenic aids available • Baking soda is a commercial version

  25. Proposed Benefits • Sodium bicarbonate supplementation increases serum pH • Desired effect is to buffer lactic acid • Reduces acidosis in the muscle cell, decreases the psychological sensation of fatigue, and increases performance in high-intensity anaerobic exercise tasks to exhaustion (~1-3 min of maximal exercise) • 400 or 800-meter sprint • 100 meter swims • 5 km bicycle races • 50% of well-controlled studies have demonstrated these effects • There is still conflicting research on the topic • Great individual variability in response

  26. Safety & Side Effects • Possible side effects of acute sodium bicarbonate supplementation • GI distress • including nausea, diarrhea and cramping • Possibly due to an increase in gastric emptying following the ingestion of alkalotic agents • Increased osmolality of the GI tract • Symptoms may be alleviated by drinking extra water with supplementation, however this may also impact the degree of alkolosis obtained

  27. Dosage & Timing • Supplements should be given 1-3 hours prior to exercise event (90 minutes seems ideal) • Leads to increased blood pH levels before, during and after an event • Most studies had subjects ingest 0.15- 0.30 g/kg • 0.30 g/kg appears to be the optimum dose, with higher dosages providing no additional benefit • This is less than 1 oz for the average adult and appears to be effective and safe • Supplementation with lower doses over longer periods of time may be just as effective, with lower risk of adverse effects • Take the same dose over 6 day period instead of at one time • Strategies to avoid/minimize GI distress during an event: • Trial supplementation during training • Drink plenty of water during treatment • After chronic ingestion for 5-6 days, d/c supplementation 2 days before the event • Intravenous infusion

  28. Sodium bicarbonate can be used as an ergogenic aid in high-intensity, comptetive cycle ergometry of 1 h durationMcNaughton et al., 1999

  29. Think Fast! Which of the following is NOT a strategy to avoid or limit GI distress when taking NaHCO3? Drink plenty of water during treatment Intravenous infusion After chronic ingestion for 5-6 days, increase dose 2 days before the event Trial supplementation during training

  30. β - Alanine • Precursor for carnosine, a dipeptide found in high concentrations in skeletal muscle • Carnosine is synthesized from the amino acids L-histidine and β–alanine • β –alanine is the rate-limiting component in the process • Chronic ingestion of β–alanine can elevate the carnosine content of human muscle by up to 80% • Carnosine plays an important role in homeostasis of contracting muscle cells, especially during high rates of anaerobic energy delivery.

  31. Carnosine • Latin for “meat/flesh” • Produced and stored in the skeletal muscle of animals but virtually absent from other organs • Absent from plants • Lacking in vegetarian diet • Content is especially high in animals involved in sprint exercise • Chickens, greyhound dogs, horses • Muscle carnosine content is highly individualized • Lower in women • Declines with age • Likely lower in vegetarians • β- alanine supplementation is one of the most powerful means to elevate muscle carnosine content • More effective than carnosine ingestion alone

  32. Proposed Mechanisms • Carnosine loading leads to improved performance in high-intensity exercise likely due to the following mechanisms • pH buffering • Undisputable physiological role as determined by its molecular structure • Protection of proteins against glycation by acting as a sacrificial peptide • Preventing the formation of protein-protein cross-links • Acting as an antioxidant • Increasing calcium sensitivity in muscle fibers enhancing force production and total work output

  33. Dosing Considerations • Daily doses of β –alanine in the amount of 4.8-6.4 grams can elevate muscle carnosine content by • 60% in 4 weeks • 80% in 10 weeks • Baguet et al., showed that the increased carnosine content in calf muscles remained elevated for > 9 weeks following supplement cessation • Doses of >10 mg/kg should be avoided • Can induce paraesthesia symptoms • No other side efects of β –alanine supplementation have been reported • Further research on the safety and possible side effects of β –alanine as a nutritional supplement is warranted.

  34. Effects of β-alanine supplementation and high intensity interval training on endurance performance and body composition in men; a double-blind trialSmith et al., 2009

  35. HMB Hydroxy-beta-methylbutyrate • A leucine-derived metabolite • Positive effects on sports performance and as a therapeutical supplement • Demonstrated by Nissen et al. in 1996 • Literature is conflicting • Reduces muscle damage and muscle catabolism and reinforces protein synthesis • Used to minimize muscle wasting in AIDS patients

  36. Background • Branched-chain amino acids (BCAAs) • Leucine • Isoleucine • Valine • Leucine and its metabolite α-ketoisocaproate (KIC) have been known to be potent anti-catabolic compounds for >35 years • Mechanisms not clearly established • Isoleucine and valine are not able to trigger these effects • HMB may be one of the key elements in the anti-catabolic effect of leucine • HMB appears to be safe at doses of 3 g/day and may even have positive impacts on overall health • Decreases in TC and LDL • Decreases in systolic BP

  37. Effects of amino acids supplement on physiological adaptations to resistance trainingKraemer et al., 2009

  38. Limited/Unsupportive Research

  39. Supportive Research

  40. Chocolate milk “Chocolate milk as a postexercise recovery aid appears to be as effective as another carbohydrate replacement beverage.” Pritchett et al., 2009

  41. Summary • Dietary supplements for athletes are not well regulated • May be contaminated • May contain substances not on the label, or may not contain what it claims to contain • Research on most ergogenic aids is limited and often conflicting – interpret with caution • Most studies used low number of subjects • Often poorly controlled • Role of the RD • Inform clients of the efficacy and safety issues surrounding nutritional supplements • Focus on those that are evidence-based (there aren’t many)! • Caution of those with limited/unsupportive research • Stress the importance of proper diet and fluid intake for athletic performance • Hydration – 20-24 oz fluid replacement for every pound lost • CHO & quality protein to fuel workouts – 3-4 hrs prior • Anabolic window – up to 30 min post workout

  42. References Cox GR, Desbrow B, Montgomery PG, Anderson ME, Bruce CR, Macrides TA, Martin DT, Moquin A, Roberts A, Hawley JA, Burke LM. Effect of different protocols of caffeine intake on metabolism and endurance performance. J Appl Physiol. 2002; 93: 990-999.  Derave W, Everaert I, Beeckman S, Baguet A. Muscle carnosine metabolism and beta-alanine supplementation in relation to exercise and training. Sprots Med. 2010; 40(3): 247-263. Hogervorst E, Bandelow S, Schmitt J, Jentjens R, Oliveira M, Allgrove J, Carter T, Gleeson M. Caffeine improves physical and cognitive performance during exhaustive exercise. Med. Sci. Sports Exerc. 2008; 40(10): 1841-1851. Kraemer WJ, Hatfield DL, Volek JS, Fragala MS, Vingren JL, Anderson JM, Spiering BA, Thomas GA, Ho JY, Quann EE, Izquierdo M, Hakkinen K, Maresh CM. Effects of amino acids supplement on physiological adaptations to resistance training. Med. Sci. Sports Exerc. 2009; 41(5): 1111-1121. Maridakis V, O’Connor PJ, Dudley GA, McCully KK. Caffeine attenuates delayed-onset muscle pain and force loss following eccentric exercise. Journal of Pain. 2007; 8(3): 237-243.  McNaughton L, Dalton B, Palmer G. Sodium bicarbonate can be used as an ergogenic aid in high-intensity, competitive cycle ergometry of 1 h duration. Eur J Appl Physiol. 1999; 80: 64-69. Pedersen DJ, Lessard SJ, Coffey VG, Chruchley EG, Wootton AM, Ng T, Watt MJ, Hawley JA. High rates of muscle glycogen resynthesis after exhaustive exercise when carbohydrate is coingested with caffeine. J Appl Physiol. 2008; 105: 7-13.  Pritchett K, Bishop P, Pritchett R, Green M, Katica C. Acute effects of chocolate mild and a commercial recovery beverage on postexercise recovery indices and endurance cycling performance. ApplPhysiolNutrMetab. 2009; 34: 1017-1022. 

  43. References Requena B, Zabala M, Padial P, Feriche B. Sodium bicarbonate and sodium citrate: ergogenic aids? J. Strength Cond. Res. 2005; 19(1): 213-224.  Smith AE, Walter AA, Graef JL, Kendall KL, Moon JR, Lockwood CM, Fukuda DH, Beck TW, Cramer JT, Stout JR. Effects of β –alanine supplementation and high-intensity interval training on endurance performance and body composition in men; a double-blind trial. Journal of the International Society of Sports Nutrition. 2009; 6:5.  Sokmen B, Armstrong LE, Kraemer WJ, Casa DJ, Dias JC, Judelson DA, Maresh CM. Caffeine use in sports: considerations for the athlete. J Strength Cond Res. 2008; 22(3): 978-986. Terjung RL, Clarkson P, Eichner R, Greenhaff PL, Hespel PJ, Israel RG, Kraemer WJ, Meyer RA, Spriet LL, Tarnopolsky MA, Wagenmakers AJM, Williams MH. The physiological and health effects of oral creatine supplementation. Med Sci Sports Exerc. 2000; 32(3): 706-717.  Vandenberghe K, Gillis N, Van Leemputte M, Van Hecke P, Vanstapel F, Hespel P. Caffeine counteracts the ergogenic action of muscle creatine loading. J Appl Physiol. 1996; 80(2): 452-457. Volek JS, Kraemer WJ, Bush JA, Boetes M, Incledon T, Clark KL, Lynch JM. Creatine supplementation enhances muscular performance during high-intensity resistance exercise. J Am Diet Assoc. 1997; 97: 765-770. Zanchi NE, Gerlinger-Romero F, Guimaraes-Ferreira L, Alves de SiqueiraFilho M, Felitti V, Lira FS, Seelaender M, Lancha AH. HMB supplementation: clinical and athletic performance-related effects and mechanisms of action. Amino Acids. 2010; 130: 1937-1945

  44. Questions?

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