NUTRITIONAL SUPPLEMENTS FOR ATHLETES LIV ENGELSEN, MS Ergogenic Aids.

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NUTRITIONAL SUPPLEMENTS FOR ATHLETES LIV ENGELSEN, MS Ergogenic Aids

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  • NUTRITIONAL SUPPLEMENTS FOR ATHLETES LIV ENGELSEN, MS Ergogenic Aids
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  • Outline Regulation of nutritional supplements In-depth review of 5 popular ergogenic aids Caffeine Creatine Monohydrate Sodium Bicarbonate Alanine HMB Overview of research to support/refute additional supplements/practices The best recovery beverage of all time Summary/Conclusion
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  • Definition Substances, devices or practices that enhance an athletes energy use, production or recovery
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  • Regulation Regulated by the Dietary Supplement Health and Education Act of 1994 (DSHEA) http://www.youtube.com/watch?v=3vxrTMYXpZo
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  • 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: o Age o Gender o Body size o Caffeine tolerance o Habituation o Cessation patterns
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  • 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 multifactorial Bottom Line: The mechanisms by which caffeine improves athletic performance is multifactorial and extends well beyond any one biologic mechanism!
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  • Effects on Body Systems & Sports Performance
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  • Tolerance Diminished responsiveness resulting from repeated exposure Caffeine tolerance has been associated with increased adenosine receptor activity and a decrease in -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
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  • Psychological Factors
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  • 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
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  • 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
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  • 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 greater ergogenic effects with more than 9 mg/kg Higher caffeine intake may blunt cognitive performance Gender differences Men tolerate higher doses than women
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  • 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
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  • Research Author & Year Subjects & Methods MeasuresTreatmentResults Cox, et al., 2002 Effect of different protocols of caffeine intake on metabolism and endurance perf. 12 trained cyclists/triathletes in study A, 8 in study B Plasma/ urinry caff, rate of fat oxidation, 1)Precaf 2)Durcaf 3)Coca-cola 4)Placebo Coca-cola was equally effective in enhancing endurance Hogervorst et al., 2008 Caffeine improves physical and cognitive performance during exhaustive exercise 24 well-trained cyclists in a RCCT Series of cognitive and physiological tests 1)CHO (CHO) 2)Caffeine +CHO (CAF) 3)Placebo (BEV) Faster after CAF on both complex info processing Maridakis et al., 2007 Caffeine attenuates delayed onset muscle pain following eccentric exercise 9 low-caffeine consuming females Pain intensity, force loss during eccentric and MVIC exercise 1)Caffeine 2)Placebo Large reduction in pain following caffeine ingestion Pedersen et al., 2008 High rates of muscle glycogen resynthesis after exhaustive exercise when CHO is coingested with caff 7 trained cyclists/triathletes in a Randomized, DB Crossover design BG, insulin, caff levels, muscle metabolites, muscle glycogen, protein kinases 1)CHO 2)CHO + Caff After 4 hrs of recovery, muscle glycogen was higher in Caff
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  • Think Fast! What has the highest caffeine content? a) Brewed tea b) Shot of espresso c) Brewed coffee d) Dark chocolate bar
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  • 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
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  • 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
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  • 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
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  • 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?
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  • 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
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  • Special Considerations Research suggests people may be responders or non-responders Characteristics of nonresponers include : 1) Higher initial levels of creatine and PCr 2) 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- creatine monohydrate Theoretically, dehydration, muscle cramps and heatstroke can occur Drink plenty of water!!!!!
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  • Creatine supplementation enhances muscular performance during high-intensity resistance exercise Volek et al., 1997 Subjects & Methods MeasuresTreatmentResults 14 active men DB RCT Bench press (PB)protocol and jump squat (JS) protocol Three different occasions (T1, T2, T3) Each separated by 6 days Total reps for bench press Peak power output for jump squats Body mass Skinfold thickness Pre and post- exercise lactate PL: Placebo CR: Creatine Prior to T1: No supplementation Prior to T2: Everyone got placebo Prior to T3: CR group took 25g/day for 6 days Lifting performance was not altered for either exercise after PL CR improved peak power output during all 5 sets of JS and improvement in reps during all 5 sets of BPs. CR increased body mass by 1.4 kg
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  • Think Fast! For maintenance of normal creatine and PCr levels, the average adult needs to replace ___ of creatine/day a) 1 g b) 2 g c) 3 g d) 4 g
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  • 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
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  • 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
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  • 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
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  • 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: a) Trial supplementation during training b) Drink plenty of water during treatment c) After chronic ingestion for 5-6 days, d/c supplementation 2 days before the event d) Intravenous infusion
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  • Sodium bicarbonate can be used as an ergogenic aid in high-intensity, comptetive cycle ergometry of 1 h duration McNaughton et al., 1999 Subjects & Methods MeasuresTreatmentResults 10 male, well trained cyclists 3 tests, in a RDB fashion Blood samples taken: 90 min prior every 30 min prior 10 min intervals throughout 1,3,5,10 min post-ex Blood Analysis: pH Blood NaHCO 3 PO 2 PCO2 Blood lactate Ergometer Data: Work output Power output Heart rate C: control 60 min ride P: placebo 60 min ride + equimolar dose of NaCl E: experimental 60 min ride + 300 mg/kg NaHCO 3 Subjects in E completed greater amounts of work than either C or P Subjects in E had greater power output than C or P No change in peak power or power:mass Blood pH was increased in E prior to testing Blood lactate was lower in E throughout test
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  • Think Fast! Which of the following is NOT a strategy to avoid or limit GI distress when taking NaHCO3? a) Drink plenty of water during treatment b) Intravenous infusion c) After chronic ingestion for 5-6 days, increase dose 2 days before the event d) Trial supplementation during training
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  • - Alanine Precursor for carnosine, a dipeptide found in high concentrations in skeletal muscle Carnosine is synthesized from the amino acids L-histidine and alanine alanine is the rate-limiting component in the process Chronic ingestion of 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.
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  • 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 - alanine supplementation is one of the most powerful means to elevate muscle carnosine content More effective than carnosine ingestion alone
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  • 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
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  • Dosing Considerations Daily doses of 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 alanine supplementation have been reported Further research on the safety and possible side effects of alanine as a nutritional supplement is warranted.
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  • Effects of -alanine supplementation and high intensity interval training on endurance performance and body composition in men; a double-blind trial Smith et al., 2009 Subjects & Methods MeasuresTreatmentResults 46 active college- aged men DB RCT 6 weeks of HIIT consisting of 5-6 bouts of a 2:1 cycling work to rest ratio Determination of VO 2 peak VO 2 peak VO 2 TTE VT Cycling test TTE TWD W Body composition % body fat Fat mass Lean body mass PL: placebo 16.5 g dextrose BA: -alanine 1.5 g -alanine + 15 g dextrose First 21 days: 4x/day (6 g/day) Next 21 days: 2x/day (3 g/day) Improvements in VO 2 peak, VO 2 TTE and TWD after 3 wks in both groups Increases in VO 2 peak, VO 2 TTE and TWD and LBM were only significant for the BA group after 2 nd 3 wks of training
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  • 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
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  • Background Branched-chain amino acids (BCAAs) Leucine Isoleucine Valine Leucine and its metabolite -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
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  • Effects of amino acids supplement on physiological adaptations to resistance training Kraemer et al., 2009 Subjects & Methods MeasuresTreatmentResults 17 healthy men in a DB RCT Performed 12 wks of heavy resistance training Blood samples taken every 2 wks Body mass Lean body mass % body fat Muscle circumference Maximal power Testosterone Cortisol Growth Hormone Creatine kinase MA: Muscle Armor 1.5 g HMB, 7 g arginine, 7 g glutamine, 3 g taurine, and dextrose CON: Control Isocaloric control MA led to greater gains in LBM, muscle strength and power MA promoted increases in resting and exercise-induced testosterone and GH MA decreased CK, indicating recuction in muscle damage
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  • Limited/Unsupportive Research SupplementProposed Action Research to Support Side EffectsLegality Carnitine Increases fat metabolism Refutes, no benefitsNoneLegal Chromium Increases lean muscle mass Refutes, no benefit unless prior deficiency Potentially dangerous if >400 mg/day Legal Coenzyme Q10 Enhances electron transport, improves endurance Limited, does not support use for athletes Appears safeLegal DHEA (dehydroepiandrosterone) Prohormone that increases lean muscle mass Refutes, no benefits for athletes NoneLegal MCT Increases energy and muscle cell mass, delays fatigue LimitedIntestinal cramping and diarrhea Legal Zinc Increases endurance, mental alertness/concent. LimitedNone if taken in recommended doses Legal
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  • Supportive Research SupplementProposed Action Research to Support Side EffectsLegality Anabolic Steroids Increases strength, LMM & Motivation SupportsSignificant, dangerous Illegal Blood doping Increases aerobic capacity SupportsSignificant, dangerous Illegal Energy Gels & Sports Drinks Increases endurance by supplying CHO, fluid and lytes SupportsNoneLegal Growth Hormone Increases LMM, strength & power SupportsEnlargement of organs & increased risk of disease Banned by WADA Protein Optimizes muscular growth & repair SupportsNone unless underlying cond. Legal
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  • Chocolate milk Chocolate milk as a postexercise recovery aid appears to be as effective as another carbohydrate replacement beverage. Pritchett et al., 2009
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  • 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 arent 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
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  • 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, OConnor 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. Appl Physiol Nutr Metab. 2009; 34: 1017-1022.
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  • 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 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 Siqueira Filho 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
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  • Questions?