8,099
edits
Changes
From Fellrnr.com, Running tips
no edit summary
|-
|}
=Caffeine and Dehydration=
Caffeine does not impact performance in hot/humid conditions, nor act as a diuretic when running<ref name="CaffDiuretic"/>. Caffeine at 360mg is a diuretic at rest, but not at 180mg or less<ref name="CaffDiureticDose"/>. Caffeine does not cause long term dehydration<ref name="Caff11day"/>, and black tea has been shown to hydrate as well as water<ref name="CaffTea"/>. Caffeine does result in increased sodium excretion in the urine<ref name="CaffSodium"/>, but the significance of this unclear.
* While caffeine could reduce the altitude problems that prevent sleep, the stimulant nature of caffeine may offset these benefits.
Caffeine has a shorter duration of effect at high altitude, possibly due to increased blood flow to the liver, and withdrawal from caffeine would likely make altitude problems more severe<ref name="CafAltitude"/>.
=Glucose Absorption, Insulin Resistance and Glycemic index =
Caffeine changes the way glucose is absorbed, but this effect is different for those at rest compared with those exercising.
[[File:Caffeine Tea Brewing Time.jpg|right|thumb|200px|Brewing time and levels of Caffeine (CF), the catechins epigallocatechin gallate (EGCG), epicatechin gallate (ECG), epigallocatechin (EGC) and epicatechin (EC)<ref name="ShishikuraKhokhar2005"/>.]]
It is claimed that tea is the second most popular drink after water<ref name="Macfarlane"/>, but it does not appear to be commonly used by athletes. Because the level of caffeine can vary dramatically with different types of tea, and different brewing methods, it is difficult to know how much caffeine is in a particular drink of tea. Generally black tea has more than oolong tea which has more than green tea<ref name="Lin-2003"/>. Typically black tea contains 28 to 46mg of Caffeine per 8oz cup<ref name="Bunker-1979"/>. This unpredictability makes tea a problematic source of caffeine, though using the same tea and brewing for the same time will give reproducible levels, but you won't know the absolute caffeine intake.
==Gels ($2-8/100mg)==
Gels are available with and without caffeine, and the caffeinated variety normally has 25mg, though some go as high as 100mg. The higher caffeine concentrations often include a coffee extract, which may limit the benefits. Given that gels typically cost $1-2 per gel, the caffeine cost is $2-8/100mg. See [[Comparison of Energy Gels]] for more details.
* Tea may help reduce dementia<ref name="CaffTeaDementSong12"/>, and tea improves learning in rats<ref name="CaffTeaRelaxJune99"/>.
* Theanine and cystine may help reduce the immune system depression of high intensity training<ref name="CaffTheanImune09"/><ref name="CaffTheanImune10"/>.
=Caffeine, Running and Sudden Death=
While rare, the sudden death of a runner does occur and often makes the news. Running is estimated to have a mortality rate of about 1 in 7,000 runners, or one death per 396,000 man-hours<ref name="Thompson-1982"/>. Sudden death during a marathon is rarer, at less than 1 in 50,000<ref name="MaronPoliac1996"/><ref name="RobertsMaron2005"/>.
==Caffeine and Myocardial Blood Flow ==
A moderate amount of caffeine does not change the myocardial blood flow at rest, but during exercise the caffeine significantly reduces the flow<ref name="Namdar-2009"/><ref name="Namdar-2006"/>. This decrease in myocardial blood flow is worse at altitude<ref name="Namdar-2006"/> and in people with Coronary artery disease<ref name="Namdar-2009"/>. (These changes were seen with 200mg of caffeine, but the studies did not try other amounts to see of the effect varies with dose.) The change in myocardial blood flow is not a risk factor for healthy individuals<ref name="Namdar-2009"/><ref name="Namdar-2006"/>, but for those with Coronary artery disease the combination of caffeine and exercise may exacerbate their condition.
==Caffeine and Irregular Heart Beats==
[http://en.wikipedia.org/wiki/Cardiac_arrhythmia Cardiac arrhythmias] (irregular heartbeats) are a group of conditions where the heart does not beat normally and can be a life threatening emergency. There is a common belief that caffeine is linked to some types of arrhythmias, but this does not seem scientifically supported for <ref name="RashidHines2006"/><ref name="Katan-2005"/><ref name="Pelchovitz-2011"/>. In fact, an animal study showed that moderate caffeine reduces the risk of atrial fibrillation<ref name="RashidHines2006"/>. A study giving recent heart attacks 450mg of caffeine showed no change in the risk of arrythmia<ref name="Myers-1990"/>. Giving 200mg of caffeine before a bicycle stress test to patients who have malignant ventricular arrhythmias made no difference<ref name="Graboys-1989"/>. However, there are anecdotal reports of people having arrhythmia triggered by caffeine. Note that a caffeine overdoes can result in heart problems<ref name="Pelchovitz-2011"/>.
==Evaluating the risks==
Because coronary artery disease may not have any initial symptoms<ref name="MayoCAD"/>, risk evaluation is tricky. Some runners who died suddenly had high cholesterol, high blood pressure or chest pains<ref name="WallerRoberts1980"/>. Other risk factors include diabetes, smoking, family history of heart attacks, obesity, long term alcohol use. If you have any risk factors for coronary artery disease, it would be prudent to talk to a healthcare professional.
=Caffeine and health =
For most people, caffeine is generally taken as tea or coffee, to the bulk of the scientific evidence around the health impact of caffeine is based on these beverages.
* Any athlete that does not effectively use either caffeine or carbohydrate is at a distinct disadvantage
This comparison indicates to me that caffeine is not against the spirit of the sport, or unethical.
=Newborn babies and Caffeine =
Newborn babies may be subject to higher levels of caffeine from breast milk than one would expect. If we assume:
=References=
<references>
<ref name="Martín-2007">{{Cite journal | last1 = I. Martín | first1 = I, MA. | last2 = López-Vílchez | first2 = MA, A. | last3 = Mur | first3 = A, O. | last4 = García-Algar | first4 = O, S. | last5 = Rossi | first5 = S, E. | last6 = Marchei | first6 = E, S. | last7 = Pichini | first7 = S. | title = , Neonatal withdrawal syndrome after chronic maternal drinking of mate. | journal = , Ther Drug Monit | , volume = 29 | , issue = 1 | , pages = 127-9 | month = , Feb | year = 2007 | , doi = [http://dx.doi.org/10.1097/FTD.0b013e31803257ed 10.1097/FTD.0b013e31803257ed | ], PMID = [http://www.ncbi.nlm.nih.gov/pubmed/17304161 17304161 }}]</ref><ref name="McGowan-1988">{{Cite journal | last1 = McGowan | first1 = JD. | last2 = Altman | first2 = McGowan, RE. | last3 = Kanto | first3 = Altman, WP. | title = Kanto, Neonatal withdrawal symptoms after chronic maternal ingestion of caffeine. | journal = , South Med J | , volume = 81 | , issue = 9 | , pages = 1092-4 | month = , Sep | year = 1988 | doi = | , PMID = [http://www.ncbi.nlm.nih.gov/pubmed/3420441 3420441 }}]</ref><ref name="Stavchansky-">{{Cite journal | last1 = Stavchansky | first1 = S. | last2 = Combs | first2 = Stavchansky, A. | last3 = Sagraves | first3 = Combs, R. | last4 = Delgado | first4 = Sagraves, M. | last5 = Joshi | first5 = Delgado, A. | title = Joshi, Pharmacokinetics of caffeine in breast milk and plasma after single oral administration of caffeine to lactating mothers. | journal = , Biopharm Drug Dispos | , volume = 9 | , issue = 3 | , pages = 285-99 | month = | year = | doi = | , PMID = [http://www.ncbi.nlm.nih.gov/pubmed/3395670 3395670 }}]</ref>
<ref name="CaffBabyMilk">How much expressed milk will my baby need? : KellyMom http://www.kellymom.com/bf/pumping/milkcalc.html </ref>
<ref name="Landolt-1995-2">{{Cite journal | last1 = Landolt | first1 = HP. | last2 = Werth | first2 = Landolt, E. | last3 = Borbély | first3 = Werth, AA. | last4 = Dijk | first4 = Borbély, DJ. | title = Dijk, Caffeine intake (200 mg) in the morning affects human sleep and EEG power spectra at night. | journal = , Brain Res | , volume = 675 | , issue = 1-2 | , pages = 67-74 | month = , Mar | year = 1995 | doi = | , PMID = [http://www.ncbi.nlm.nih.gov/pubmed/7796154 7796154 }}]</ref><ref name="Landolt-1995">{{Cite journal | last1 = Landolt | first1 = HP. | last2 = Dijk | first2 = Landolt, DJ. | last3 = Gaus | first3 = Dijk, SE. | last4 = Borbély | first4 = Gaus, AA. | title = Borbély, Caffeine reduces low-frequency delta activity in the human sleep EEG. | journal = , Neuropsychopharmacology | , volume = 12 | , issue = 3 | , pages = 229-38 | month = , May | year = 1995 | , doi = [http://dx.doi.org/10.1016/0893-133X(94)00079-F 10.1016/0893-133X(94)00079-F | ], PMID = [http://www.ncbi.nlm.nih.gov/pubmed/7612156 7612156 }}]</ref>
<ref name="CaffTeaCancer">Tea and cancer prevention: epidemiological stu... [Pharmacol Res. 2011] - PubMed - NCBI http://www.ncbi.nlm.nih.gov/pubmed/21419224 </ref>
<ref name="CaffTheanImune10">Cystine and Theanine Supplementation Restores High-Intensity... : The Journal of Strength & Conditioning Research http://journals.lww.com/nsca-jscr/Abstract/2010/03000/Cystine_and_Theanine_Supplementation_Restores.34.aspx </ref>
<ref name="CafMusclePain">Effect of caffeine on quadricep... [Int J Sport Nutr Exerc Metab. 2009] - PubMed - NCBI http://www.ncbi.nlm.nih.gov/pubmed/19478340 </ref>
<ref name="CafMusclePainHeat">Caffeine lowers muscle pain during exercise in... [Physiol Behav. 2011] - PubMed - NCBI http://www.ncbi.nlm.nih.gov/pubmed/21163281 </ref>
<ref name="Graham-1991">{{Cite journal | last1 = Graham | first1 = TE. | last2 = Spriet | first2 = Graham, LL. | title = Spriet, Performance and metabolic responses to a high caffeine dose during prolonged exercise. | journal = , J Appl Physiol | , volume = 71 | , issue = 6 | , pages = 2292-8 | month = , Dec | year = 1991 | doi = | , PMID = [http://www.ncbi.nlm.nih.gov/pubmed/1778925 1778925 }}]</ref><ref name="Pasman-1995">{{Cite journal | last1 = WJ. Pasman | first1 = WJ, MA. | last2 = van Baak | first2 = MA, AE. | last3 = Jeukendrup | first3 = AE, A. | last4 = de Haan | first4 = A. | title = , The effect of different dosages of caffeine on endurance performance time. | journal = , Int J Sports Med | , volume = 16 | , issue = 4 | , pages = 225-30 | month = , May | year = 1995 | , doi [http://dx.doi = .org/10.1055/s-2007-972996 10.1055/s-2007-972996 | ], PMID = [http://www.ncbi.nlm.nih.gov/pubmed/7657415 7657415 }}]</ref>
<ref name="CaffRedBull">Nutrition Facts and Analysis for Energy drink, RED BULL, with added caffeine, niacin, pantothenic acid, vitamins B6 and B12 http://nutritiondata.self.com/facts/beverages/7399/2 </ref>
<ref name="Macfarlane">{{cite book|author=Alan Macfarlane|coauthors=, Iris Macfarlane|title=!!coauthors!!, The Empire of Tea|publisher=, The Overlook Press|!!publisher!!, isbn=1-58567-493-1|, 32 !!page=32|year=!!, 2004}}</ref><ref name="Lin-2003">{{Cite journal | last1 = Lin | first1 = YS. | last2 = Tsai | first2 = Lin, YJ. | last3 = Tsay | first3 = Tsai, JS. | last4 = Lin | first4 = Tsay, JK. | title = Lin, Factors affecting the levels of tea polyphenols and caffeine in tea leaves. | journal = , J Agric Food Chem | , volume = 51 | , issue = 7 | , pages = 1864-73 | month = , Mar | year = 2003 | , doi = [http://dx.doi.org/10.1021/jf021066b 10.1021/jf021066b | ], PMID = [http://www.ncbi.nlm.nih.gov/pubmed/12643643 12643643 }}]</ref><ref name="ShishikuraKhokhar2005">{{cite journal|last1=Yoko Shishikura|first1=Yoko|last2=, Santosh Khokhar|first2=Santosh|title=, Factors affecting the levels of catechins and caffeine in tea beverage: estimated daily intakes and antioxidant activity|journal=, Journal of the Science of Food and Agriculture|, volume=85|, issue=12|year=, 2005|, pages=2125–2133|, ISSN [http://www.worldcat.org/issn=/0022-5142 0022-5142|], doi [http://dx.doi=.org/10.1002/jsfa.2206 10.1002/jsfa.2206}}]</ref><ref name="Bunker-1979">{{Cite journal | last1 = Bunker | first1 = ML. | last2 = McWilliams | first2 = Bunker, M. | title = McWilliams, Caffeine content of common beverages. | journal = , J Am Diet Assoc | , volume = 74 | , issue = 1 | , pages = 28-32 | month = , Jan | year = 1979 | doi = | , PMID = [http://www.ncbi.nlm.nih.gov/pubmed/762339 762339 }}]</ref><ref name="ChouBell2007">{{cite journal|last1=Chou|first1=K.-H.|last2=Bell|first2=Chou, L.N.|title=Bell, Caffeine Content of Prepackaged National-Brand and Private-Label Carbonated Beverages|journal=, Journal of Food Science|, volume=72|, issue=6|year=, 2007|, pages=C337–C342|, ISSN [http://www.worldcat.org/issn=/0022-1147 0022-1147|], doi [http://dx.doi=.org/10.1111/j.1750-3841.2007.00414.x 10.1111/j.1750-3841.2007.00414.x}}]</ref>
<ref name="CaffDeFizz">Fueling Properly for an Ultra | Running Times Magazine http://runningtimes.com/Article.aspx?ArticleID=21791 </ref>
<ref name="Buscicchio-2012">{{Cite journal | last1 = Buscicchio | first1 = G. | last2 = Piemontese | first2 = Buscicchio, M. | last3 = Gentilucci | first3 = Piemontese, L. | last4 = Ferretti | first4 = Gentilucci, F. | last5 = Tranquilli | first5 = Ferretti, AL. | title = Tranquilli, The effects of maternal caffeine and chocolate intake on fetal heart rate. | journal = , J Matern Fetal Neonatal Med | , volume = 25 | , issue = 5 | , pages = 528-30 | month = , May | year = 2012 | , doi [http://dx.doi = .org/10.3109/14767058.2011.636104 10.3109/14767058.2011.636104 | ], PMID = [http://www.ncbi.nlm.nih.gov/pubmed/22502981 22502981 }}]</ref>
<ref name="CaffStarbucks">The Complete Guide to Starbucks Caffeine http://www.energyfiend.com/the-complete-guide-to-starbucks-caffeine </ref>
<ref name="CaffDatabase">Caffeine Content of Drinks http://www.energyfiend.com/the-caffeine-database\# </ref>
<ref name="Stern2011">{{cite journal|last1=Judith Stern|first1=Judith|title=, Coffee and muscle cramps|journal=, Neuromuscular Disorders|, volume=21|, issue=5|year=, 2011|, pages=375|, ISSN [http://www.worldcat.org/issn=/09608966 09608966|], doi [http://dx.doi=.org/10.1016/j.nmd.2011.03.007 10.1016/j.nmd.2011.03.007}}]</ref><ref name="Dubowitz2011">{{cite journal|last1=Victor Dubowitz|first1=Victor|title=, Muscle cramps and coffee|journal=, Neuromuscular Disorders|, volume=21|, issue=3|year=, 2011|, pages=235|, ISSN [http://www.worldcat.org/issn=/09608966 09608966|], doi=[http://dx.doi.org/10.1016/j.nmd.2011.01.004 10.1016/j.nmd.2011.01.004}}]</ref><ref name="Voermansvan Engelen2011">{{cite journal|last1=Voermans|first1=N.C.|last2=van Engelen|first2=Voermans, B.G.|title=van Engelen, Coffee and muscle cramps|journal=, Neuromuscular Disorders|, volume=21|, issue=12|year=, 2011|, pages=832|, ISSN [http://www.worldcat.org/issn=/09608966 09608966|], doi [http://dx.doi=.org/10.1016/j.nmd.2011.07.006 10.1016/j.nmd.2011.07.006}}]</ref><ref name="Venables-2008">{{Cite journal | last1 = Venables | first1 = MC. | last2 = Hulston | first2 = Venables, CJ. | last3 = Cox | first3 = Hulston, HR. | last4 = Jeukendrup | first4 = Cox, AE. | title = Jeukendrup, Green tea extract ingestion, fat oxidation, and glucose tolerance in healthy humans. | journal = , Am J Clin Nutr | , volume = 87 | , issue = 3 | , pages = 778-84 | month = , Mar | year = 2008 | doi = | , PMID = [http://www.ncbi.nlm.nih.gov/pubmed/18326618 18326618 }}]</ref>
<ref name="MayoCAD">Coronary artery disease: Symptoms - MayoClinic.com http://www.mayoclinic.com/health/coronary-artery-disease/DS00064/DSECTION=symptoms </ref>
<ref name="Thompson-1982"> {{Cite journal | last1 = Thompson | first1 = PD. | last2 = Funk | first2 = Thompson, EJ. | last3 = Carleton | first3 = Funk, RA. | last4 = Sturner | first4 = Carleton, WQ. | title = Sturner, Incidence of death during jogging in Rhode Island from 1975 through 1980. | journal = , JAMA | , volume = 247 | , issue = 18 | , pages = 2535-8 | month = , May | year = 1982 | doi = | , PMID = [http://www.ncbi.nlm.nih.gov/pubmed/6978411 6978411 }}]</ref><ref name="RobertsMaron2005">{{cite journal|last1=Roberts|first1=William O.|last2=Maron|first2=Roberts, Barry J.|title=Maron, Evidence for Decreasing Occurrence of Sudden Cardiac Death Associated With the Marathon|journal=, Journal of the American College of Cardiology|, volume=46|, issue=7|year=, 2005|, pages=1373–1374|, ISSN [http://www.worldcat.org/issn=/07351097 07351097|], doi [http://dx.doi=.org/10.1016/j.jacc.2005.07.008 10.1016/j.jacc.2005.07.008}}]</ref><ref name="MaronPoliac1996">{{cite journal|last1=Maron|first1=Barry J.|last2=Poliac|first2=Maron, Liviu C.|last3=Roberts|first3=Poliac, William O.|title=Roberts, Risk for sudden cardiac death associated with marathon running|journal=, Journal of the American College of Cardiology|, volume=28|, issue=2|year=, 1996|, pages=428–431|, ISSN [http://www.worldcat.org/issn=/07351097 07351097|], doi [http://dx.doi=.org/10.1016/0735-1097(96)00137-4 10.1016/0735-1097(96)00137-4}}]</ref><ref name="WallerRoberts1980">{{cite journal|last1=Waller|first1=Bruce F.|last2=Roberts|first2=Waller, William C.|title=Roberts, Sudden death while running in conditioned runners aged 40 years or over|journal=, The American Journal of Cardiology|, volume=45|, issue=6|year=, 1980|, pages=1292–1300|, ISSN [http://www.worldcat.org/issn=/00029149 00029149|], doi=[http://dx.doi.org/10.1016/0002-9149(80)90491-9 10.1016/0002-9149(80)90491-9}}]</ref><ref name="Namdar-2009"> {{Cite journal | last1 = Namdar | first1 = M. | last2 = Schepis | first2 = Namdar, T. | last3 = Koepfli | first3 = Schepis, P. | last4 = Gaemperli | first4 = Koepfli, O. | last5 = Siegrist | first5 = Gaemperli, PT. | last6 = Grathwohl | first6 = Siegrist, R. | last7 = Valenta | first7 = Grathwohl, I. | last8 = Delaloye | first8 = Valenta, R. | last9 = Klainguti | first9 = Delaloye, M. | title = Klainguti, Caffeine impairs myocardial blood flow response to physical exercise in patients with coronary artery disease as well as in age-matched controls. | journal = , PLoS One | , volume = 4 | , issue = 5 | , pages = e5665 | month = , | year = 2009 | , doi [http://dx.doi = .org/10.1371/journal.pone.0005665 10.1371/journal.pone.0005665 | ], PMID = [http://www.ncbi.nlm.nih.gov/pubmed/19479069 19479069 }}]</ref><ref name="Namdar-2006"> {{Cite journal | last1 = Namdar | first1 = M. | last2 = Koepfli | first2 = Namdar, P. | last3 = Grathwohl | first3 = Koepfli, R. | last4 = Siegrist | first4 = Grathwohl, PT. | last5 = Klainguti | first5 = Siegrist, M. | last6 = Schepis | first6 = Klainguti, T. | last7 = Delaloye | first7 = Schepis, R. | last8 = Wyss | first8 = Delaloye, CA. | last9 = Fleischmann | first9 = Wyss, SP. | title = Fleischmann, Caffeine decreases exercise-induced myocardial flow reserve. | journal = , J Am Coll Cardiol | , volume = 47 | , issue = 2 | , pages = 405-10 | month = , Jan | year = 2006 | , doi [http://dx.doi = .org/10.1016/j.jacc.2005.08.064 10.1016/j.jacc.2005.08.064 | ], PMID = [http://www.ncbi.nlm.nih.gov/pubmed/16412869 16412869 }}]</ref><ref name="MaronEpstein1986">{{cite journal|last1=Maron|first1=Barry J.|last2=Epstein|first2=Maron, Stephen E.|last3=Roberts|first3=Epstein, William C.|title=Roberts, Causes of sudden death in competitive athletes|journal=, Journal of the American College of Cardiology|, volume=7|, issue=1|year=, 1986|, pages=204–214|, ISSN [http://www.worldcat.org/issn=/07351097 07351097|], doi [http://dx.doi=.org/10.1016/S0735-1097(86)80283-2 10.1016/S0735-1097(86)80283-2}}]</ref><ref name="RashidHines2006">{{cite journal|last1=Abdul Rashid|first1=Abdul|last2=, Mujahid Hines|first2=Mujahid|last3=Scherlag|first3=, Benjamin J.|last4=Yamanashi|first4=Scherlag, William S.|last5=Yamanashi, William Lovallo|first5=William|title=, The effects of caffeine on the inducibility of atrial fibrillation|journal=, Journal of Electrocardiology|, volume=39|, issue=4|year=, 2006|, pages=421–425|, ISSN [http://www.worldcat.org/issn=/00220736 00220736|], doi [http://dx.doi=.org/10.1016/j.jelectrocard.2005.12.007 10.1016/j.jelectrocard.2005.12.007}}]</ref><ref name="Katan-2005"> {{Cite journal | last1 = Katan | first1 = MB. | last2 = Schouten | first2 = Katan, E. | title = Schouten, Caffeine and arrhythmia. | journal = , Am J Clin Nutr | , volume = 81 | , issue = 3 | , pages = 539-40 | month = , Mar | year = 2005 | doi = | , PMID = [http://www.ncbi.nlm.nih.gov/pubmed/15755819 15755819 }}]</ref><ref name="Pelchovitz-2011"> {{Cite journal | last1 = Pelchovitz | first1 = DJ. | last2 = Goldberger | first2 = Pelchovitz, JJ. | title = Goldberger, Caffeine and cardiac arrhythmias: a review of the evidence. | journal = , Am J Med | , volume = 124 | , issue = 4 | , pages = 284-9 | month = , Apr | year = 2011 | , doi [http://dx.doi = .org/10.1016/j.amjmed.2010.10.017 10.1016/j.amjmed.2010.10.017 | ], PMID = [http://www.ncbi.nlm.nih.gov/pubmed/21435415 21435415 }}]</ref><ref name="Myers-1990"> {{Cite journal | last1 = Myers | first1 = MG. | last2 = Harris | first2 = Myers, L. | title = Harris, High dose caffeine and ventricular arrhythmias. | journal = , Can J Cardiol | , volume = 6 | , issue = 3 | , pages = 95-8 | month = , Apr | year = 1990 | doi = | , PMID = [http://www.ncbi.nlm.nih.gov/pubmed/1692755 1692755 }}]</ref><ref name="Graboys-1989"> {{Cite journal | last1 = Graboys | first1 = TB. | last2 = Blatt | first2 = Graboys, CM. | last3 = Lown | first3 = Blatt, B. | title = Lown, The effect of caffeine on ventricular ectopic activity in patients with malignant ventricular arrhythmia. | journal = , Arch Intern Med | , volume = 149 | , issue = 3 | , pages = 637-9 | month = , Mar | year = 1989 | doi = | , PMID = [http://www.ncbi.nlm.nih.gov/pubmed/2465748 2465748 }}]</ref><ref name="Pettitt-2012"> {{Cite journal | last1 = Pettitt | first1 = RW. | last2 = Niemeyer | first2 = Pettitt, JD. | last3 = Sexton | first3 = Niemeyer, PJ. | last4 = Lipetzky | first4 = Sexton, A. | last5 = Murray | first5 = Lipetzky, SR. | title = Murray, Do the non-caffeine ingredients of energy drinks affect metabolic responses to heavy exercise? | journal = , J Strength Cond Res | volume = | issue = | pages = | month = , Oct | year = 2012 | , doi [http://dx.doi = .org/10.1519/JSC.0b013e3182736e31 10.1519/JSC.0b013e3182736e31 | ], PMID = [http://www.ncbi.nlm.nih.gov/pubmed/23037611 23037611 }}]</ref>
<ref name="Parsons-1981">Parsons, William D., and Allen H. Neims. "Prolonged half-life of caffeine in healthy term newborn infants." Journal of Pediatrics 98.4 (1981): 640-641.</ref>
</references>
