Where did Tailwind really come from? Direct experience, testing with endurance athletes here in Durango, Colorado, and some of the best scientific minds studying endurance nutrition:
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Ferguson-Stegall L, McCleave EL, Ding Z, Kammer LM, Wang B, Doerner PG, Liu Y, Ivy JL. 2010. The effect of a low carbohydrate beverage with added protein on cycling endurance performance in trained athletes. J Strength Cond Res24(10):2577-86.https://www.ncbi.nlm.nih.gov/pubmed/20733521
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Jentjens RL, Achten J, Jeukendrup AE. 2004. High oxidation rates from combined carbohydrates ingested during exercise. Med Sci Sports Exerc. 36(9):1551-8. https://www.ncbi.nlm.nih.gov/pubmed/15354037
Jeukendrup, A. E., & Moseley, L. (2010). Multiple transportable carbohydrates enhance gastric emptying and fluid delivery. Scand J Med Sci Sports, 20(1), 112-121. https://www.ncbi.nlm.nih.gov/pubmed/19000102
Jeukendrup, Asker, and Michael Gleeson. Sport Nutrition : An Introduction to Energy Production and Performance. 2nd ed. New York: Human Kinetics, 2010. https://www.amazon.com/Sport-Nutrition-Asker-Ph-D-Jeukendrup/dp/1492529036/
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Murray, Robert. "The Effects of Consuming Carbohydrate-Electrolyte Beverages on Gastric Emptying and Fluid Absorption During and Following Exercise." Sports Medicine 4.5 (1987): 322-51.
https://link.springer.com/article/10.2165/00007256-198704050-00002
Murray, PhD, FACSM, Bob. "Preventing Dehydration: Sports Drinks or Water."GSSI.com. Gatorade Sports Science Institute, 20 May 2005. Web. 20 May 2013. https://sites.uni.edu/dolgener/UG_Sport_Nutrition/Articles/Preventing_Dehydration_GSSI.pdf
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Saunders MJ, Kane MD, Todd MK. 2004. Effects of a carbohydrate-protein beverage on cycling endurance and muscle damage. Med Sci Sports Exerc 36(7):1233-38. https://www.ncbi.nlm.nih.gov/pubmed/15235331
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Stearns RL, Emmanuel H, Volek JS, Casa DJ. 2010. Effects of ingesting protein in combination with carbohydrate during exercise on endurance performance: A systematic review with meta-analysis. J Strength Cond Res 24(8):2191-202. https://www.ncbi.nlm.nih.gov/pubmed/20683237
Valentine RJ, Saunders MJ, Todd MK, St Laurent TG. 2008. Influence of carbohydrate-protein beverage on cycling endurance and indices of muscle disruption. Int J Sport Nutr Exerc Metab 18(4):363-78. https://www.ncbi.nlm.nih.gov/pubmed/18708686
Wright, E. M., & Loo, D. D. (2000). Coupling between Na+, sugar, and water transport across the intestine. Ann N Y Acad Sci, 915, 54-66. https://www.ncbi.nlm.nih.gov/pubmed/11193601
Zeuthen, T., Belhage, B., & Zeuthen, E. (2006). Water transport by Na+-coupled cotransporters of glucose (SGLT1) and of iodide (NIS). The dependence of substrate size studied at high resolution. J Physiol, 570(Pt 3), 485-499. https://www.ncbi.nlm.nih.gov/pubmed/16322051
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CAFFEINE
Articles of interest to learn more about caffeine and endurance.
International society of sports nutrition position stand: caffeine and performance
Influence of caffeine and carbohydrate feedings on endurance performance
Effect of different protocols of caffeine intake on metabolism and endurance performance
The Effects of Carbohydrate, Caffeine and Protein on Endurance Performance