{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T19:23:47Z","timestamp":1792783427120,"version":"4.5.0"},"reference-count":91,"publisher":"Springer Science and Business Media LLC","issue":"10","license":[{"start":{"date-parts":[[2026,6,8]],"date-time":"2026-06-08T00:00:00Z","timestamp":1780876800000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2026,6,8]],"date-time":"2026-06-08T00:00:00Z","timestamp":1780876800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"name":"Auckland University of Technology","id":[{"id":"https:\/\/ror.org\/01zvqw119","id-type":"ROR","asserted-by":"crossref"}]}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Sports Med"],"published-print":{"date-parts":[[2026,10]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>\n                    Ultra-high carbohydrate (U-HC) ingestion strategies, typically\u2009&gt;\u200990\u00a0g\u00b7h\u207b\n                    <jats:sup>1<\/jats:sup>\n                    , have gained remarkable traction among elite endurance athletes in recent years. This rise has been fuelled by anecdotal reports linking aggressive carbohydrate fuelling with superior race execution, and record-breaking performances. However, the scientific literature supporting these practices remains limited, and current frameworks used to explain carbohydrate-mediated performance effects, such as muscle glycogen sparing, maintenance of blood glucose or maximisation of exogenous carbohydrate oxidation, do not fully account for the reported U-HC benefits. Indeed, available studies reveal a disconnect between metabolic data and the real-world adoption of intakes far beyond established oxidation ceilings. We examine the existing research on carbohydrate ingestion during endurance exercise, highlighting the metabolic responses and performance outcomes. We identify how traditional mechanisms have been interpreted to justify escalating carbohydrate intake and discuss the constraints of current methodologies in detecting meaningful performance benefits at ultra-high ingestion rates. The article then introduces emerging, yet largely untested, possible mechanistic models that may underpin the perceived utility of U-HC fuelling, including shifts in substrate selection, enhanced lactate shuttling and potential central effects associated with carbohydrate availability. Finally, we explore the relevance of inter-individual variation in carbohydrate oxidation capacity and the implications for developing practical guidelines for athletes. By integrating physiological, metabolic and perceptual perspectives, this current opinion outlines why U-HC strategies have gained prominence and identifies key areas where further research is required to clarify their role within contemporary endurance performance for the masses.\n                  <\/jats:p>","DOI":"10.1007\/s40279-026-02462-z","type":"journal-article","created":{"date-parts":[[2026,6,8]],"date-time":"2026-06-08T04:58:00Z","timestamp":1780894680000},"page":"2367-2388","update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Fuelled or Fooled? Examining the Evidence and Mechanisms Behind Ultra-High Carbohydrate Intake in Endurance Athletes"],"prefix":"10.1007","volume":"56","author":[{"ORCID":"https:\/\/orcid.org\/0009-0006-1528-7907","authenticated-orcid":false,"given":"Daniel J.","family":"Plews","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Paul D.","family":"Booth","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Taj","family":"Krieger","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ed","family":"Maunder","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2026,6,8]]},"reference":[{"key":"2462_CR1","doi-asserted-by":"publisher","DOI":"10.1016\/j.tjnut.2026.101442","volume":"156","author":"JP Morton","year":"2026","unstructured":"Morton JP, Fell JM, Gonzalez JT, Hearris MA, Podlogar T, Pugh JN, et al. From metabolism to medals: contemporary perspectives and revisiting carbohydrate guidelines for fueling endurance athletes during exercise. J Nutr. 2026;156:101442. https:\/\/doi.org\/10.1016\/j.tjnut.2026.101442.","journal-title":"J Nutr"},{"key":"2462_CR2","doi-asserted-by":"publisher","first-page":"1581","DOI":"10.1152\/japplphysiol.00665.2025","volume":"139","author":"S Ravikanti","year":"2025","unstructured":"Ravikanti S, Silang KG, Martyn HJ, Johnson KO, Louis JB, Bampouras TM, et al. 13 C-labelled glucose-fructose show greater exogenous and whole-body CHO oxidation and lower O2 cost of running at 120 versus 60 and 90 g\u00b7h\u22121 in elite male marathoners. J Appl Physiol. 2025;139:1581\u201395. https:\/\/doi.org\/10.1152\/japplphysiol.00665.2025.","journal-title":"J Appl Physiol"},{"key":"2462_CR3","doi-asserted-by":"publisher","first-page":"753","DOI":"10.1007\/s40279-024-02131-z","volume":"55","author":"JA Rothschild","year":"2025","unstructured":"Rothschild JA, Hofmeyr S, McLaren SJ, Maunder E. A novel method to predict carbohydrate and energy expenditure during endurance exercise using measures of training load. Sports Med. 2025;55:753\u201374. https:\/\/doi.org\/10.1007\/s40279-024-02131-z.","journal-title":"Sports Med"},{"key":"2462_CR4","doi-asserted-by":"publisher","DOI":"10.3390\/nu17050918","volume":"17","author":"W Cao","year":"2025","unstructured":"Cao W, He Y, Fu R, Chen Y, Yu J, He Z. A review of carbohydrate supplementation approaches and strategies for optimizing performance in elite long-distance endurance. Nutrients. 2025;17:918. https:\/\/doi.org\/10.3390\/nu17050918.","journal-title":"Nutrients"},{"key":"2462_CR5","doi-asserted-by":"publisher","first-page":"C710","DOI":"10.1152\/ajpcell.00583.2024","volume":"328","author":"PJ Prins","year":"2025","unstructured":"Prins PJ, Noakes TD, Buga A, Gerhart HD, Cobb BM, D\u2019Agostino DP, et al. Carbohydrate ingestion eliminates hypoglycemia and improves endurance exercise performance in triathletes adapted to very low- and high-carbohydrate isocaloric diets. Am J Physiol-Cell Physiol. 2025;328:C710\u201327. https:\/\/doi.org\/10.1152\/ajpcell.00583.2024.","journal-title":"Am J Physiol-Cell Physiol"},{"key":"2462_CR6","doi-asserted-by":"publisher","first-page":"2393","DOI":"10.1007\/s00421-022-05019-w","volume":"122","author":"T Podlogar","year":"2022","unstructured":"Podlogar T, Bokal \u0160, Cirnski S, Wallis GA. Increased exogenous but unaltered endogenous carbohydrate oxidation with combined fructose-maltodextrin ingested at 120 g h\u22121 versus 90 g h\u22121 at different ratios. Eur J Appl Physiol. 2022;122:2393\u2013401. https:\/\/doi.org\/10.1007\/s00421-022-05019-w.","journal-title":"Eur J Appl Physiol"},{"key":"2462_CR7","doi-asserted-by":"publisher","DOI":"10.1152\/japplphysiol.00861.2025","author":"JA Rothschild","year":"2025","unstructured":"Rothschild JA, Dudley-Rode H, Carpenter H, Smith A, Plews DJ, Maunder E. Carbohydrate ingestion during prolonged exercise and net skeletal muscle glycogen utilization: a meta-analysis. J Appl Physiol. 2025. https:\/\/doi.org\/10.1152\/japplphysiol.00861.2025.","journal-title":"J Appl Physiol"},{"key":"2462_CR8","doi-asserted-by":"publisher","first-page":"1349","DOI":"10.1007\/s00421-024-05687-w","volume":"125","author":"H Dudley-Rode","year":"2025","unstructured":"Dudley-Rode H, Zinn C, Plews DJ, Charoensap T, Maunder E. Carbohydrate ingestion during prolonged exercise blunts the reduction in power output at the moderate-to-heavy intensity transition. Eur J Appl Physiol. 2025;125:1349\u201359. https:\/\/doi.org\/10.1007\/s00421-024-05687-w.","journal-title":"Eur J Appl Physiol"},{"key":"2462_CR9","doi-asserted-by":"publisher","first-page":"E672","DOI":"10.1152\/ajpendo.1999.276.4.E672","volume":"276","author":"AE Jeukendrup","year":"1999","unstructured":"Jeukendrup AE, Wagenmakers AJM, Stegen JHCH, Gijsen AP, Brouns F, Saris WHM. Carbohydrate ingestion can completely suppress endogenous glucose production during exercise. Am J Physiol Endocrinol Metab. 1999;276:E672\u201383. https:\/\/doi.org\/10.1152\/ajpendo.1999.276.4.E672.","journal-title":"Am J Physiol Endocrinol Metab"},{"key":"2462_CR10","doi-asserted-by":"publisher","first-page":"E1032","DOI":"10.1152\/ajpendo.00376.2015","volume":"309","author":"JT Gonzalez","year":"2015","unstructured":"Gonzalez JT, Fuchs CJ, Smith FE, Thelwall PE, Taylor R, Stevenson EJ, et al. Ingestion of glucose or sucrose prevents liver but not muscle glycogen depletion during prolonged endurance-type exercise in trained cyclists. Am J Physiol-Endocrinol Metab. 2015;309:E1032\u20139. https:\/\/doi.org\/10.1152\/ajpendo.00376.2015.","journal-title":"Am J Physiol-Endocrinol Metab"},{"key":"2462_CR11","doi-asserted-by":"publisher","first-page":"191","DOI":"10.1210\/endrev\/bnaf038","volume":"47","author":"TD Noakes","year":"2026","unstructured":"Noakes TD, Prins PJ, Buga A, D\u2019Agostino DP, Volek JS, Koutnik AP. Carbohydrate ingestion on exercise metabolism and physical performance. Endocr Rev. 2026;47:191\u2013243. https:\/\/doi.org\/10.1210\/endrev\/bnaf038.","journal-title":"Endocr Rev"},{"key":"2462_CR12","doi-asserted-by":"publisher","first-page":"344","DOI":"10.1249\/MSS.0b013e31822dc809","volume":"44","author":"B Pfeiffer","year":"2012","unstructured":"Pfeiffer B, Stellingwerff T, Hodgson AB, Randell R, P\u00f6ttgen K, Res P, et al. Nutritional intake and gastrointestinal problems during competitive endurance events. Med Sci Sports Exerc. 2012;44:344\u201351. https:\/\/doi.org\/10.1249\/MSS.0b013e31822dc809.","journal-title":"Med Sci Sports Exerc"},{"key":"2462_CR13","doi-asserted-by":"publisher","DOI":"10.3390\/nu12051367","author":"A Viribay","year":"2020","unstructured":"Viribay A, Arribalzaga S, Mielgo-Ayuso J, Casta\u00f1eda-Babarro A, Seco-Calvo J, Urdampilleta A. Effects of 120 g\/h of carbohydrates intake during a mountain marathon on exercise-induced muscle damage in elite runners. Nutrients. 2020. https:\/\/doi.org\/10.3390\/nu12051367.","journal-title":"Nutrients"},{"key":"2462_CR14","doi-asserted-by":"publisher","first-page":"452","DOI":"10.1097\/MCO.0b013e328339de9f","volume":"13","author":"AE Jeukendrup","year":"2010","unstructured":"Jeukendrup AE. Carbohydrate and exercise performance: the role of multiple transportable carbohydrates. Curr Opin Clin Nutr Metab Care. 2010;13:452\u20137. https:\/\/doi.org\/10.1097\/MCO.0b013e328339de9f.","journal-title":"Curr Opin Clin Nutr Metab Care"},{"key":"2462_CR15","doi-asserted-by":"publisher","first-page":"501","DOI":"10.1016\/j.jand.2015.12.006","volume":"116","author":"DT Thomas","year":"2016","unstructured":"Thomas DT, Erdman KA, Burke LM. Position of the Academy of Nutrition and Dietetics, Dietitians of Canada, and the American College of Sports Medicine: nutrition and athletic performance. J Acad Nutr Diet. 2016;116:501\u201328. https:\/\/doi.org\/10.1016\/j.jand.2015.12.006.","journal-title":"J Acad Nutr Diet"},{"key":"2462_CR16","doi-asserted-by":"publisher","first-page":"S17","DOI":"10.1080\/02640414.2011.585473","volume":"29","author":"LM Burke","year":"2011","unstructured":"Burke LM, Hawley JA, Wong SHS, Jeukendrup AE. Carbohydrates for training and competition. J Sports Sci. 2011;29:S17-27. https:\/\/doi.org\/10.1080\/02640414.2011.585473.","journal-title":"J Sports Sci"},{"key":"2462_CR17","doi-asserted-by":"publisher","unstructured":"American College of Sports Medicine, American Dietetic Association, Dietitians of Canada. Nutrition and athletic performance. Med Sci Sports Exerc. 2016;48:543\u201368. https:\/\/doi.org\/10.1249\/MSS.0000000000000852.","DOI":"10.1249\/MSS.0000000000000852"},{"key":"2462_CR18","doi-asserted-by":"publisher","first-page":"140","DOI":"10.1111\/j.1748-1716.1967.tb03720.x","volume":"71","author":"J Bergstr\u00f6m","year":"1967","unstructured":"Bergstr\u00f6m J, Hermansen L, Hultman E, Saltin B. Diet, muscle glycogen and physical performance. Acta Physiol Scand. 1967;71:140\u201350. https:\/\/doi.org\/10.1111\/j.1748-1716.1967.tb03720.x.","journal-title":"Acta Physiol Scand"},{"key":"2462_CR19","doi-asserted-by":"publisher","first-page":"129","DOI":"10.1111\/j.1748-1716.1967.tb03608.x","volume":"70","author":"B Ahlborg","year":"1967","unstructured":"Ahlborg B, Bergstr\u00f6m J, Ekelund L, Hultman E. Muscle glycogen and muscle electrolytes during prolonged physical exercise1. Acta Physiol Scand. 1967;70:129\u201342. https:\/\/doi.org\/10.1111\/j.1748-1716.1967.tb03608.x.","journal-title":"Acta Physiol Scand"},{"key":"2462_CR20","doi-asserted-by":"publisher","first-page":"218","DOI":"10.3109\/00365516709090629","volume":"19","author":"J Bergstr\u00f6m","year":"1967","unstructured":"Bergstr\u00f6m J, Hultman E. A study of the glycogen metabolism during exercise in man. Scand J Clin Lab Invest. 1967;19:218\u201328. https:\/\/doi.org\/10.3109\/00365516709090629.","journal-title":"Scand J Clin Lab Invest"},{"key":"2462_CR21","doi-asserted-by":"publisher","first-page":"1285","DOI":"10.1152\/japplphysiol.01023.2003","volume":"96","author":"RLPG Jentjens","year":"2004","unstructured":"Jentjens RLPG, Venables MC, Jeukendrup AE. Oxidation of exogenous glucose, sucrose, and maltose during prolonged cycling exercise. J Appl Physiol. 2004;96:1285\u201391. https:\/\/doi.org\/10.1152\/japplphysiol.01023.2003.","journal-title":"J Appl Physiol"},{"key":"2462_CR22","doi-asserted-by":"publisher","first-page":"275","DOI":"10.1249\/mss.0b013e31815adf19","volume":"40","author":"K Currell","year":"2008","unstructured":"Currell K, Jeukendrup AE. Superior endurance performance with ingestion of multiple transportable carbohydrates. Med Sci Sports Exerc. 2008;40:275\u201381. https:\/\/doi.org\/10.1249\/mss.0b013e31815adf19.","journal-title":"Med Sci Sports Exerc"},{"key":"2462_CR23","doi-asserted-by":"publisher","DOI":"10.14814\/phy2.13555","volume":"6","author":"AJ King","year":"2018","unstructured":"King AJ, O\u2019Hara JP, Morrison DJ, Preston T, King RFGJ. Carbohydrate dose influences liver and muscle glycogen oxidation and performance during prolonged exercise. Physiol Rep. 2018;6:e13555. https:\/\/doi.org\/10.14814\/phy2.13555.","journal-title":"Physiol Rep"},{"key":"2462_CR24","doi-asserted-by":"publisher","DOI":"10.3389\/fnut.2024.1507572","volume":"11","author":"TD Noakes","year":"2025","unstructured":"Noakes TD, Prins PJ. Are very high rates of exogenous carbohydrate ingestion (>90 g\/hr) sufficient or indeed necessary to run a sub-2hr marathon? An analysis of the model predictions of Lukasiewicz and colleagues. Front Nutr. 2025;11:1507572. https:\/\/doi.org\/10.3389\/fnut.2024.1507572.","journal-title":"Front Nutr"},{"key":"2462_CR25","doi-asserted-by":"publisher","first-page":"1394","DOI":"10.1152\/japplphysiol.00091.2022","volume":"132","author":"MA Hearris","year":"2022","unstructured":"Hearris MA, Pugh JN, Langan-Evans C, Mann SJ, Burke L, Stellingwerff T, et al. 13 C-glucose-fructose labeling reveals comparable exogenous CHO oxidation during exercise when consuming 120 g\/h in fluid, gel, jelly chew, or coingestion. J Appl Physiol. 2022;132:1394\u2013406. https:\/\/doi.org\/10.1152\/japplphysiol.00091.2022.","journal-title":"J Appl Physiol"},{"key":"2462_CR26","doi-asserted-by":"publisher","first-page":"468","DOI":"10.1152\/jappl.1992.72.2.468","volume":"72","author":"NJ Rehrer","year":"1992","unstructured":"Rehrer NJ, Wagenmakers AJ, Beckers EJ, Halliday D, Leiper JB, Brouns F, et al. Gastric emptying, absorption, and carbohydrate oxidation during prolonged exercise. J Appl Physiol. 1992;72:468\u201375. https:\/\/doi.org\/10.1152\/jappl.1992.72.2.468.","journal-title":"J Appl Physiol"},{"key":"2462_CR27","doi-asserted-by":"publisher","first-page":"238","DOI":"10.1055\/s-2007-1024799","volume":"11","author":"N Rehrer","year":"1990","unstructured":"Rehrer N, Brouns F, Beckers E, Ten Hoor F, Saris WH. Gastric emptying with repeated drinking during running and bicycling. Int J Sports Med. 1990;11:238\u201343. https:\/\/doi.org\/10.1055\/s-2007-1024799.","journal-title":"Int J Sports Med"},{"key":"2462_CR28","doi-asserted-by":"publisher","DOI":"10.3390\/nu12072094","volume":"12","author":"A Urdampilleta","year":"2020","unstructured":"Urdampilleta A, Arribalzaga S, Viribay A, Casta\u00f1eda-Babarro A, Seco-Calvo J, Mielgo-Ayuso J. Effects of 120 vs. 60 and 90 g\/h carbohydrate intake during a trail marathon on neuromuscular function and high intensity run capacity recovery. Nutrients. 2020;12:2094. https:\/\/doi.org\/10.3390\/nu12072094.","journal-title":"Nutrients"},{"key":"2462_CR29","doi-asserted-by":"publisher","first-page":"1814","DOI":"10.1080\/02640414.2015.1012104","volume":"33","author":"KJ Stuempfle","year":"2015","unstructured":"Stuempfle KJ, Hoffman MD. Gastrointestinal distress is common during a 161-km ultramarathon. J Sports Sci. 2015;33:1814\u201321. https:\/\/doi.org\/10.1080\/02640414.2015.1012104.","journal-title":"J Sports Sci"},{"key":"2462_CR30","doi-asserted-by":"publisher","first-page":"683","DOI":"10.1152\/jappl.1976.41.5.683","volume":"41","author":"G Ahlborg","year":"1976","unstructured":"Ahlborg G, Felig P. Influence of glucose ingestion on fuel-hormone response during prolonged exercise. J Appl Physiol. 1976;41:683\u20138. https:\/\/doi.org\/10.1152\/jappl.1976.41.5.683.","journal-title":"J Appl Physiol"},{"key":"2462_CR31","doi-asserted-by":"publisher","first-page":"419","DOI":"10.1123\/ijsnem.2017-0337","volume":"28","author":"MK Torstveit","year":"2018","unstructured":"Torstveit MK, Fahrenholtz I, Stenqvist TB, Sylta \u00d8, Melin A. Within-day energy deficiency and metabolic perturbation in male endurance athletes. Int J Sport Nutr Exerc Metab. 2018;28:419\u201327. https:\/\/doi.org\/10.1123\/ijsnem.2017-0337.","journal-title":"Int J Sport Nutr Exerc Metab"},{"key":"2462_CR32","doi-asserted-by":"publisher","first-page":"336","DOI":"10.1249\/MSS.0b013e31827205d1","volume":"45","author":"JW Smith","year":"2013","unstructured":"Smith JW, Pascoe DD, Passe DH, Ruby BC, Stewart LK, Baker LB, et al. Curvilinear dose\u2013response relationship of carbohydrate (0\u2013120 g\u00b7h\u22121) and performance. Med Sci Sports Exerc. 2013;45:336\u201341. https:\/\/doi.org\/10.1249\/MSS.0b013e31827205d1.","journal-title":"Med Sci Sports Exerc"},{"key":"2462_CR33","doi-asserted-by":"publisher","first-page":"2823","DOI":"10.1113\/JP281127","volume":"599","author":"JM Fell","year":"2021","unstructured":"Fell JM, Hearris MA, Ellis DG, Moran JEP, Jevons EFP, Owens DJ, et al. Carbohydrate improves exercise capacity but does not affect subcellular lipid droplet morphology, AMPK and p53 signalling in human skeletal muscle. J Physiol. 2021;599:2823\u201349. https:\/\/doi.org\/10.1113\/JP281127.","journal-title":"J Physiol"},{"key":"2462_CR34","doi-asserted-by":"publisher","first-page":"1157","DOI":"10.1007\/s00421-019-04106-9","volume":"119","author":"AJ King","year":"2019","unstructured":"King AJ, O\u2019Hara JP, Arjomandkhah NC, Rowe J, Morrison DJ, Preston T, et al. Liver and muscle glycogen oxidation and performance with dose variation of glucose\u2013fructose ingestion during prolonged (3 h) exercise. Eur J Appl Physiol. 2019;119:1157\u201369. https:\/\/doi.org\/10.1007\/s00421-019-04106-9.","journal-title":"Eur J Appl Physiol"},{"key":"2462_CR35","doi-asserted-by":"publisher","first-page":"1344","DOI":"10.1016\/j.nut.2014.03.023","volume":"30","author":"AMW Yau","year":"2014","unstructured":"Yau AMW, McLaughlin J, Maughan RJ, Gilmore W, Evans GH. Short-term dietary supplementation with fructose accelerates gastric emptying of a fructose but not a glucose solution. Nutrition. 2014;30:1344\u20138. https:\/\/doi.org\/10.1016\/j.nut.2014.03.023.","journal-title":"Nutrition"},{"key":"2462_CR36","doi-asserted-by":"publisher","first-page":"258","DOI":"10.3390\/nu9030258","volume":"9","author":"A Yau","year":"2017","unstructured":"Yau A, McLaughlin J, Maughan R, Gilmore W, Evans G. The effect of short-term dietary fructose supplementation on gastric emptying rate and gastrointestinal hormone responses in healthy men. Nutrients. 2017;9:258. https:\/\/doi.org\/10.3390\/nu9030258.","journal-title":"Nutrients"},{"key":"2462_CR37","doi-asserted-by":"publisher","first-page":"547","DOI":"10.1139\/apnm-2016-0453","volume":"42","author":"RJS Costa","year":"2017","unstructured":"Costa RJS, Miall A, Khoo A, Rauch C, Snipe R, Cam\u00f5es-Costa V, et al. Gut-training: the impact of two weeks repetitive gut-challenge during exercise on gastrointestinal status, glucose availability, fuel kinetics, and running performance. Appl Physiol Nutr Metab. 2017;42:547\u201357. https:\/\/doi.org\/10.1139\/apnm-2016-0453.","journal-title":"Appl Physiol Nutr Metab"},{"key":"2462_CR38","doi-asserted-by":"publisher","first-page":"630","DOI":"10.1111\/sms.12912","volume":"28","author":"A Miall","year":"2018","unstructured":"Miall A, Khoo A, Rauch C, Snipe RMJ, Cam\u00f5es-Costa VL, Gibson PR, et al. Two weeks of repetitive gut-challenge reduce exercise-associated gastrointestinal symptoms and malabsorption. Scand J Med Sci Sports. 2018;28:630\u201340. https:\/\/doi.org\/10.1111\/sms.12912.","journal-title":"Scand J Med Sci Sports"},{"key":"2462_CR39","doi-asserted-by":"publisher","first-page":"126","DOI":"10.1152\/japplphysiol.00950.2009","volume":"109","author":"GR Cox","year":"2010","unstructured":"Cox GR, Clark SA, Cox AJ, Halson SL, Hargreaves M, Hawley JA, et al. Daily training with high carbohydrate availability increases exogenous carbohydrate oxidation during endurance cycling. J Appl Physiol. 2010;109:126\u201334. https:\/\/doi.org\/10.1152\/japplphysiol.00950.2009.","journal-title":"J Appl Physiol"},{"key":"2462_CR40","unstructured":"Hutchinson A. Why endurance athletes are scarfing down more carbs. Outs Mag. 2023. https:\/\/www.outsideonline.com\/health\/nutrition\/carb-loading-endurance-athletes\/. Accessed 24 Sept 2025"},{"key":"2462_CR41","doi-asserted-by":"publisher","first-page":"2253","DOI":"10.1152\/jappl.1994.76.6.2253","volume":"76","author":"GA Brooks","year":"1994","unstructured":"Brooks GA, Mercier J. Balance of carbohydrate and lipid utilization during exercise: the \u201ccrossover\u201d concept. J Appl Physiol. 1994;76:2253\u201361. https:\/\/doi.org\/10.1152\/jappl.1994.76.6.2253.","journal-title":"J Appl Physiol"},{"key":"2462_CR42","doi-asserted-by":"publisher","first-page":"158","DOI":"10.1152\/japplphysiol.00521.2023","volume":"136","author":"CJ Lukasiewicz","year":"2024","unstructured":"Lukasiewicz CJ, Vandiver KJ, Albert ED, Kirby BS, Jacobs RA. Assessing exogenous carbohydrate intake needed to optimize human endurance performance across sex: insights from modeling runners pursuing a sub-2-h marathon. J Appl Physiol. 2024;136:158\u201376. https:\/\/doi.org\/10.1152\/japplphysiol.00521.2023.","journal-title":"J Appl Physiol"},{"key":"2462_CR43","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pone.0234027","volume":"15","author":"LM Burke","year":"2020","unstructured":"Burke LM, Sharma AP, Heikura IA, Forbes SF, Holloway M, McKay AKA, et al. Crisis of confidence averted: impairment of exercise economy and performance in elite race walkers by ketogenic low carbohydrate, high fat (LCHF) diet is reproducible. PLoS ONE. 2020;15:e0234027. https:\/\/doi.org\/10.1371\/journal.pone.0234027.","journal-title":"PLoS ONE"},{"key":"2462_CR44","doi-asserted-by":"publisher","first-page":"171","DOI":"10.2147\/OAJSM.S180409","volume":"10","author":"FT McSwiney","year":"2019","unstructured":"McSwiney FT, Doyle L, Plews DJ, Zinn C. Impact of ketogenic diet on athletes: current insights. Open Access J Sports Med. 2019;10:171\u201383. https:\/\/doi.org\/10.2147\/OAJSM.S180409.","journal-title":"Open Access J Sports Med"},{"key":"2462_CR45","doi-asserted-by":"publisher","first-page":"2785","DOI":"10.1113\/JP273230","volume":"595","author":"LM Burke","year":"2017","unstructured":"Burke LM, Ross ML, Garvican-Lewis LA, Welvaert M, Heikura IA, Forbes SG, et al. Low carbohydrate, high fat diet impairs exercise economy and negates the performance benefit from intensified training in elite race walkers. J Physiol. 2017;595:2785\u2013807. https:\/\/doi.org\/10.1113\/JP273230.","journal-title":"J Physiol"},{"key":"2462_CR46","doi-asserted-by":"publisher","first-page":"194","DOI":"10.1152\/japplphysiol.00813.2005","volume":"100","author":"L Havemann","year":"2006","unstructured":"Havemann L, West SJ, Goedecke JH, Macdonald IA, St Clair Gibson A, Noakes TD, et al. Fat adaptation followed by carbohydrate loading compromises high-intensity sprint performance. J Appl Physiol. 2006;100:194\u2013202. https:\/\/doi.org\/10.1152\/japplphysiol.00813.2005.","journal-title":"J Appl Physiol"},{"key":"2462_CR47","doi-asserted-by":"publisher","first-page":"2896","DOI":"10.3390\/nu13082896","volume":"13","author":"J Cao","year":"2021","unstructured":"Cao J, Lei S, Wang X, Cheng S. The effect of a ketogenic low-carbohydrate, high-fat diet on aerobic capacity and exercise performance in endurance athletes: a systematic review and meta-analysis. Nutrients. 2021;13:2896. https:\/\/doi.org\/10.3390\/nu13082896.","journal-title":"Nutrients"},{"key":"2462_CR48","doi-asserted-by":"publisher","first-page":"1627404","DOI":"10.3389\/fnut.2025.1627404","volume":"12","author":"T Noakes","year":"2025","unstructured":"Noakes T, Buga A, Volek J, Prins P. Identification of a reverse crossover point during moderate-intensity exercise (>6 h; 69% VO2max) in a world-class triathlete\u2014a secondary analysis. Front Nutr. 2025;12:1627404. https:\/\/doi.org\/10.3389\/fnut.2025.1627404.","journal-title":"Front Nutr"},{"key":"2462_CR49","doi-asserted-by":"publisher","unstructured":"Dant B, Cummings P, Noakes T, Prins P. Substrate-corrected VO\u2082 models for improved interpretation of movement economy: technical report. J Exerc Nutr. 2025. https:\/\/doi.org\/10.53520\/jen2025.103212","DOI":"10.53520\/jen2025.103212"},{"key":"2462_CR50","doi-asserted-by":"publisher","first-page":"1071","DOI":"10.3945\/ajcn.2010.29566","volume":"92","author":"V Lecoultre","year":"2010","unstructured":"Lecoultre V, Benoit R, Carrel G, Schutz Y, Millet GP, Tappy L, et al. Fructose and glucose co-ingestion during prolonged exercise increases lactate and glucose fluxes and oxidation compared with an equimolar intake of glucose. Am J Clin Nutr. 2010;92:1071\u20139. https:\/\/doi.org\/10.3945\/ajcn.2010.29566.","journal-title":"Am J Clin Nutr"},{"key":"2462_CR51","doi-asserted-by":"publisher","DOI":"10.1016\/j.redox.2020.101454","volume":"35","author":"GA Brooks","year":"2020","unstructured":"Brooks GA. Lactate as a fulcrum of metabolism. Redox Biol. 2020;35:101454. https:\/\/doi.org\/10.1016\/j.redox.2020.101454.","journal-title":"Redox Biol"},{"key":"2462_CR52","doi-asserted-by":"publisher","first-page":"25","DOI":"10.1007\/s40279-014-0148-z","volume":"44","author":"A Jeukendrup","year":"2014","unstructured":"Jeukendrup A. A step towards personalized sports nutrition: carbohydrate intake during exercise. Sports Med. 2014;44:25\u201333. https:\/\/doi.org\/10.1007\/s40279-014-0148-z.","journal-title":"Sports Med"},{"key":"2462_CR53","doi-asserted-by":"publisher","first-page":"E571","DOI":"10.1152\/ajpendo.2000.278.4.E571","volume":"278","author":"H Dubouchaud","year":"2000","unstructured":"Dubouchaud H, Butterfield GE, Wolfel EE, Bergman BC, Brooks GA. Endurance training, expression, and physiology of LDH, MCT1, and MCT4 in human skeletal muscle. Am J Physiol Endocrinol Metab. 2000;278:E571\u20139. https:\/\/doi.org\/10.1152\/ajpendo.2000.278.4.E571.","journal-title":"Am J Physiol Endocrinol Metab"},{"key":"2462_CR54","doi-asserted-by":"publisher","first-page":"57","DOI":"10.1007\/s40279-018-1029-7","volume":"49","author":"C Brietzke","year":"2019","unstructured":"Brietzke C, Franco-Alvarenga PE, Coelho-J\u00fanior HJ, Silveira R, Asano RY, Pires FO. Effects of carbohydrate mouth rinse on cycling time trial performance: a systematic review and meta-analysis. Sports Med. 2019;49:57\u201366. https:\/\/doi.org\/10.1007\/s40279-018-1029-7.","journal-title":"Sports Med"},{"key":"2462_CR55","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1155\/2011\/385962","volume":"2011","author":"E-JM Fares","year":"2011","unstructured":"Fares E-JM, Kayser B. Carbohydrate mouth rinse effects on exercise capacity in pre- and postprandial states. J Nutr Metab. 2011;2011:1\u20136. https:\/\/doi.org\/10.1155\/2011\/385962.","journal-title":"J Nutr Metab"},{"key":"2462_CR56","doi-asserted-by":"publisher","first-page":"651","DOI":"10.1111\/sms.13393","volume":"29","author":"SK Learsi","year":"2019","unstructured":"Learsi SK, Ghiarone T, Silva\u2010Cavalcante MD, Andrade\u2010Souza VA, Ataide\u2010Silva T, Bertuzzi R, et al. Cycling time trial performance is improved by carbohydrate ingestion during exercise regardless of a fed or fasted state. Scand J Med Sci Sports. 2019;29:651\u201362. https:\/\/doi.org\/10.1111\/sms.13393.","journal-title":"Scand J Med Sci Sports"},{"key":"2462_CR57","doi-asserted-by":"publisher","first-page":"1326","DOI":"10.1249\/MSS.0b013e3181967637","volume":"41","author":"JL Steiner","year":"2009","unstructured":"Steiner JL, Curmaci AA, Patrie JT, Gaesser GA, Weltman A. Effects of carbohydrate supplementation on the RPE-blood lactate relationship. Med Sci Sports Exerc. 2009;41:1326\u201333. https:\/\/doi.org\/10.1249\/MSS.0b013e3181967637.","journal-title":"Med Sci Sports Exerc"},{"key":"2462_CR58","doi-asserted-by":"publisher","first-page":"12","DOI":"10.1123\/ijsnem.2024-0097","volume":"35","author":"A Ijaz","year":"2025","unstructured":"Ijaz A, Collins AJ, Moreno-Caba\u00f1as A, Bradshaw L, Hutchins K, Betts JA, et al. Exogenous glucose oxidation during exercise is positively related to body size. Int J Sport Nutr Exerc Metab. 2025;35:12\u201323. https:\/\/doi.org\/10.1123\/ijsnem.2024-0097.","journal-title":"Int J Sport Nutr Exerc Metab"},{"key":"2462_CR59","doi-asserted-by":"publisher","DOI":"10.1186\/s44410-025-00003-9","volume":"1","author":"T Podlogar","year":"2025","unstructured":"Podlogar T, Cooper-Smith N, Gonzalez JT, Wallis GA. Personalised carbohydrate feeding during exercise based on exogenous glucose oxidation: a proof-of-concept study. Perform Nutr. 2025;1:2. https:\/\/doi.org\/10.1186\/s44410-025-00003-9.","journal-title":"Perform Nutr"},{"key":"2462_CR60","doi-asserted-by":"publisher","DOI":"10.3389\/fnut.2023.1084021","volume":"10","author":"PJ Prins","year":"2023","unstructured":"Prins PJ, Noakes TD, Buga A, D\u2019Agostino DP, Volek JS, Buxton JD, et al. Low and high carbohydrate isocaloric diets on performance, fat oxidation, glucose and cardiometabolic health in middle age males. Front Nutr. 2023;10:1084021. https:\/\/doi.org\/10.3389\/fnut.2023.1084021.","journal-title":"Front Nutr"},{"key":"2462_CR61","doi-asserted-by":"publisher","first-page":"1376","DOI":"10.1249\/MSS.0000000000002262","volume":"52","author":"JFP Barber","year":"2020","unstructured":"Barber JFP, Thomas J, Narang B, Hengist A, Betts JA, Wallis GA, et al. Pectin-alginate does not further enhance exogenous carbohydrate oxidation in running. Med Sci Sports Exerc. 2020;52:1376\u201384. https:\/\/doi.org\/10.1249\/MSS.0000000000002262.","journal-title":"Med Sci Sports Exerc"},{"key":"2462_CR62","doi-asserted-by":"publisher","first-page":"1653","DOI":"10.1249\/MSS.0b013e318175716c","volume":"40","author":"MC Venables","year":"2008","unstructured":"Venables MC, Brouns F, Jeukendrup AE. Oxidation of maltose and trehalose during prolonged moderate-intensity exercise. Med Sci Sports Exerc. 2008;40:1653\u20139. https:\/\/doi.org\/10.1249\/MSS.0b013e318175716c.","journal-title":"Med Sci Sports Exerc"},{"key":"2462_CR63","doi-asserted-by":"publisher","first-page":"298","DOI":"10.1139\/h11-006","volume":"36","author":"DavidS Rowlands","year":"2011","unstructured":"Rowlands DavidS, Clarke J. Lower oxidation of a high molecular weight glucose polymer vs. glucose during cycling. Appl Physiol Nutr Metab. 2011;36:298\u2013306. https:\/\/doi.org\/10.1139\/h11-006.","journal-title":"Appl Physiol Nutr Metab"},{"key":"2462_CR64","doi-asserted-by":"publisher","first-page":"1134","DOI":"10.1152\/japplphysiol.00981.2004","volume":"100","author":"AE Jeukendrup","year":"2006","unstructured":"Jeukendrup AE, Moseley L, Mainwaring GI, Samuels S, Perry S, Mann CH. Exogenous carbohydrate oxidation during ultraendurance exercise. J Appl Physiol. 2006;100:1134\u201341. https:\/\/doi.org\/10.1152\/japplphysiol.00981.2004.","journal-title":"J Appl Physiol"},{"key":"2462_CR65","doi-asserted-by":"publisher","first-page":"2030","DOI":"10.1249\/MSS.0b013e3181e0efc9","volume":"42","author":"B Pfeiffer","year":"2010","unstructured":"Pfeiffer B, Stellingwerff T, Zaltas E, Jeukendrup AE. Oxidation of solid versus liquid CHO sources during exercise. Med Sci Sports Exerc. 2010;42:2030\u20137. https:\/\/doi.org\/10.1249\/MSS.0b013e3181e0efc9.","journal-title":"Med Sci Sports Exerc"},{"key":"2462_CR66","doi-asserted-by":"publisher","first-page":"610","DOI":"10.1016\/j.metabol.2004.12.004","volume":"54","author":"RLPG Jentjens","year":"2005","unstructured":"Jentjens RLPG, Shaw C, Birtles T, Waring RH, Harding LK, Jeukendrup AE. Oxidation of combined ingestion of glucose and sucrose during exercise. Metabolism. 2005;54:610\u20138. https:\/\/doi.org\/10.1016\/j.metabol.2004.12.004.","journal-title":"Metabolism"},{"key":"2462_CR67","doi-asserted-by":"publisher","first-page":"485","DOI":"10.1079\/BJN20041368","volume":"93","author":"RLPG Jentjens","year":"2005","unstructured":"Jentjens RLPG, Jeukendrup AE. High rates of exogenous carbohydrate oxidation from a mixture of glucose and fructose ingested during prolonged cycling exercise. Br J Nutr. 2005;93:485\u201392. https:\/\/doi.org\/10.1079\/BJN20041368.","journal-title":"Br J Nutr"},{"key":"2462_CR68","doi-asserted-by":"publisher","first-page":"381","DOI":"10.1007\/BF00843733","volume":"68","author":"JA Hawley","year":"1994","unstructured":"Hawley JA, Bosch AN, Weltan SM, Dennis SC, Noakes TD. Effects of glucose ingestion or glucose infusion on fuel substrate kinetics during prolonged exercise. Eur J Appl Physiol. 1994;68:381\u20139. https:\/\/doi.org\/10.1007\/BF00843733.","journal-title":"Eur J Appl Physiol"},{"key":"2462_CR69","doi-asserted-by":"publisher","first-page":"523","DOI":"10.1007\/BF00843762","volume":"64","author":"JA Hawley","year":"1992","unstructured":"Hawley JA, Dennis SC, Nowitz A, Brouns F, Noakes TD. Exogenous carbohydrate oxidation from maltose and glucose ingested during prolonged exercise. Eur J Appl Physiol. 1992;64:523\u20137. https:\/\/doi.org\/10.1007\/BF00843762.","journal-title":"Eur J Appl Physiol"},{"key":"2462_CR70","doi-asserted-by":"publisher","DOI":"10.3389\/fnut.2020.00088","volume":"7","author":"S Pettersson","year":"2020","unstructured":"Pettersson S, Ahnoff M, Edin F, Lingstr\u00f6m P, Simark Mattsson C, Andersson-Hall U. A hydrogel drink with high fructose content generates higher exogenous carbohydrate oxidation and a reduced drop in dental biofilm pH compared to two other, commercially available, carbohydrate sports drinks. Front Nutr. 2020;7:88. https:\/\/doi.org\/10.3389\/fnut.2020.00088.","journal-title":"Front Nutr"},{"key":"2462_CR71","doi-asserted-by":"publisher","first-page":"327","DOI":"10.1249\/MSS.0b013e3181ebc488","volume":"43","author":"B Pfeiffer","year":"2011","unstructured":"Pfeiffer B, Stellingwerff T, Zaltas E, Hodgson AB, Jeukendrup AE. Carbohydrate oxidation from a drink during running compared with cycling exercise. Med Sci Sports Exerc. 2011;43:327\u201334. https:\/\/doi.org\/10.1249\/MSS.0b013e3181ebc488.","journal-title":"Med Sci Sports Exerc"},{"key":"2462_CR72","doi-asserted-by":"publisher","first-page":"1814","DOI":"10.1249\/MSS.0b013e31828e12d4","volume":"45","author":"WJ O\u2019Brien","year":"2013","unstructured":"O\u2019Brien WJ, Stannard SR, Clarke JA, Rowlands DS. Fructose\u2013maltodextrin ratio governs exogenous and other CHO oxidation and performance. Med Sci Sports Exerc. 2013;45:1814\u201324. https:\/\/doi.org\/10.1249\/MSS.0b013e31828e12d4.","journal-title":"Med Sci Sports Exerc"},{"key":"2462_CR73","doi-asserted-by":"publisher","first-page":"480","DOI":"10.1055\/s-2007-972882","volume":"17","author":"K R\u00f6cker","year":"1996","unstructured":"R\u00f6cker K, Krieg B, Niess A, Dickhuth H-H. Breath-by-breath measurements for the analysis of exogenous glucose oxidation during intense endurance exercise using [13 C]-lsotopes. Int J Sports Med. 1996;17:480\u20136. https:\/\/doi.org\/10.1055\/s-2007-972882.","journal-title":"Int J Sports Med"},{"key":"2462_CR74","doi-asserted-by":"publisher","first-page":"1976","DOI":"10.1249\/MSS.0000000000002334","volume":"52","author":"SA Mears","year":"2020","unstructured":"Mears SA, Boxer B, Sheldon D, Wardley H, Tarnowski CA, James LJ, et al. Sports drink intake pattern affects exogenous carbohydrate oxidation during running. Med Sci Sports Exerc. 2020;52:1976\u201382. https:\/\/doi.org\/10.1249\/MSS.0000000000002334.","journal-title":"Med Sci Sports Exerc"},{"key":"2462_CR75","doi-asserted-by":"publisher","DOI":"10.3390\/nu9020167","volume":"9","author":"J Trommelen","year":"2017","unstructured":"Trommelen J, Fuchs C, Beelen M, Lenaerts K, Jeukendrup A, Cermak N, et al. Fructose and sucrose intake increase exogenous carbohydrate oxidation during exercise. Nutrients. 2017;9:167. https:\/\/doi.org\/10.3390\/nu9020167.","journal-title":"Nutrients"},{"key":"2462_CR76","doi-asserted-by":"publisher","first-page":"2443","DOI":"10.1007\/s00421-011-2225-4","volume":"112","author":"DS Rowlands","year":"2012","unstructured":"Rowlands DS, Clarke J, Green JG, Shi X. l-Arginine but not l-glutamine likely increases exogenous carbohydrate oxidation during endurance exercise. Eur J Appl Physiol. 2012;112:2443\u201353. https:\/\/doi.org\/10.1007\/s00421-011-2225-4.","journal-title":"Eur J Appl Physiol"},{"key":"2462_CR77","doi-asserted-by":"publisher","first-page":"1709","DOI":"10.1152\/japplphysiol.00878.2007","volume":"104","author":"DS Rowlands","year":"2008","unstructured":"Rowlands DS, Thorburn MS, Thorp RM, Broadbent S, Shi X. Effect of graded fructose coingestion with maltodextrin on exogenous14 C-fructose and13 C-glucose oxidation efficiency and high-intensity cycling performance. J Appl Physiol. 2008;104:1709\u201319. https:\/\/doi.org\/10.1152\/japplphysiol.00878.2007.","journal-title":"J Appl Physiol"},{"key":"2462_CR78","doi-asserted-by":"publisher","first-page":"844","DOI":"10.1152\/japplphysiol.00170.2005","volume":"99","author":"SE Yeo","year":"2005","unstructured":"Yeo SE, Jentjens RLPG, Wallis GA, Jeukendrup AE. Caffeine increases exogenous carbohydrate oxidation during exercise. J Appl Physiol. 2005;99:844\u201350. https:\/\/doi.org\/10.1152\/japplphysiol.00170.2005.","journal-title":"J Appl Physiol"},{"key":"2462_CR79","doi-asserted-by":"publisher","first-page":"426","DOI":"10.1249\/01.MSS.0000155399.23358.82","volume":"37","author":"GA Wallis","year":"2005","unstructured":"Wallis GA, Rowlands DS, Shaw C, Jentjens RLPG, Jeukendrup AE. Oxidation of combined ingestion of maltodextrins and fructose during exercise. Med Sci Sports Exerc. 2005;37:426\u201332. https:\/\/doi.org\/10.1249\/01.MSS.0000155399.23358.82.","journal-title":"Med Sci Sports Exerc"},{"key":"2462_CR80","doi-asserted-by":"publisher","first-page":"1143","DOI":"10.1093\/jn\/137.5.1143","volume":"137","author":"J Achten","year":"2007","unstructured":"Achten J, Jentjens RL, Brouns F, Jeukendrup AE. Exogenous oxidation of isomaltulose is lower than that of sucrose during exercise in men. J Nutr. 2007;137:1143\u20138. https:\/\/doi.org\/10.1093\/jn\/137.5.1143.","journal-title":"J Nutr"},{"key":"2462_CR81","doi-asserted-by":"publisher","first-page":"1014","DOI":"10.1152\/jappl.1994.76.3.1014","volume":"76","author":"E Adopo","year":"1994","unstructured":"Adopo E, Peronnet F, Massicotte D, Brisson GR, Hillaire-Marcel C. Respective oxidation of exogenous glucose and fructose given in the same drink during exercise. J Appl Physiol. 1994;76:1014\u20139. https:\/\/doi.org\/10.1152\/jappl.1994.76.3.1014.","journal-title":"J Appl Physiol"},{"key":"2462_CR82","doi-asserted-by":"publisher","first-page":"357","DOI":"10.1249\/MSS.0b013e3181857ee6","volume":"41","author":"CJ Hulston","year":"2009","unstructured":"Hulston CJ, Wallis GA, Jeukendrup AE. Exogenous CHO oxidation with glucose plus fructose intake during exercise. Med Sci Sports Exerc. 2009;41:357\u201363. https:\/\/doi.org\/10.1249\/MSS.0b013e3181857ee6.","journal-title":"Med Sci Sports Exerc"},{"key":"2462_CR83","doi-asserted-by":"publisher","first-page":"1551","DOI":"10.1249\/01.MSS.0000139796.07843.1D","volume":"36","author":"RLPG Jentjens","year":"2004","unstructured":"Jentjens RLPG, Achten J, Jeukendrup AE. High oxidation rates from combined carbohydrates ingested during exercise. Med Sci Sports Exerc. 2004;36:1551\u20138. https:\/\/doi.org\/10.1249\/01.MSS.0000139796.07843.1D.","journal-title":"Med Sci Sports Exerc"},{"key":"2462_CR84","doi-asserted-by":"publisher","first-page":"835","DOI":"10.1152\/jappl.1997.82.3.835","volume":"82","author":"AE Jeukendrup","year":"1997","unstructured":"Jeukendrup AE, Mensink M, Saris WHM, Wagenmakers AJM. Exogenous glucose oxidation during exercise in endurance-trained and untrained subjects. J Appl Physiol. 1997;82:835\u201340. https:\/\/doi.org\/10.1152\/jappl.1997.82.3.835.","journal-title":"J Appl Physiol"},{"key":"2462_CR85","doi-asserted-by":"publisher","first-page":"1156","DOI":"10.1080\/17461391.2020.1813336","volume":"21","author":"BJ Narang","year":"2021","unstructured":"Narang BJ, Wallis GA, Gonzalez JT. The effect of calcium co\u2010ingestion on exogenous glucose oxidation during endurance exercise in healthy men: a pilot study. Eur J Sport Sci. 2021;21:1156\u201364. https:\/\/doi.org\/10.1080\/17461391.2020.1813336.","journal-title":"Eur J Sport Sci"},{"key":"2462_CR86","doi-asserted-by":"publisher","first-page":"G181","DOI":"10.1152\/ajpgi.00419.2010","volume":"300","author":"WJ O\u2019Brien","year":"2011","unstructured":"O\u2019Brien WJ, Rowlands DS. Fructose-maltodextrin ratio in a carbohydrate-electrolyte solution differentially affects exogenous carbohydrate oxidation rate, gut comfort, and performance. Am J Physiol Gastrointest Liver Physiol. 2011;300:G181\u20139. https:\/\/doi.org\/10.1152\/ajpgi.00419.2010.","journal-title":"Am J Physiol Gastrointest Liver Physiol"},{"key":"2462_CR87","doi-asserted-by":"publisher","first-page":"2663","DOI":"10.1249\/MSS.0000000000002426","volume":"52","author":"OJ Odell","year":"2020","unstructured":"Odell OJ, Podlogar T, Wallis GA. Comparable exogenous carbohydrate oxidation from lactose or sucrose during exercise. Med Sci Sports Exerc. 2020;52:2663\u201372. https:\/\/doi.org\/10.1249\/MSS.0000000000002426.","journal-title":"Med Sci Sports Exerc"},{"key":"2462_CR88","doi-asserted-by":"publisher","first-page":"1166","DOI":"10.1152\/japplphysiol.00105.2022","volume":"133","author":"OJ Odell","year":"2022","unstructured":"Odell OJ, Impey SG, Shad BJ, Podlogar T, Salgueiro RB, Rowlands DS, et al. Oxidation of independent and combined ingested galactose and glucose during exercise. J Appl Physiol. 2022;133:1166\u201374. https:\/\/doi.org\/10.1152\/japplphysiol.00105.2022.","journal-title":"J Appl Physiol"},{"key":"2462_CR89","doi-asserted-by":"publisher","first-page":"2038","DOI":"10.1249\/MSS.0b013e3181e0efe6","volume":"42","author":"B Pfeiffer","year":"2010","unstructured":"Pfeiffer B, Stellingwerff T, Zaltas E, Jeukendrup AE. CHO oxidation from a CHO gel compared with a drink during exercise. Med Sci Sports Exerc. 2010;42:2038\u201345. https:\/\/doi.org\/10.1249\/MSS.0b013e3181e0efe6.","journal-title":"Med Sci Sports Exerc"},{"key":"2462_CR90","doi-asserted-by":"publisher","DOI":"10.3389\/fnut.2021.810041","volume":"8","author":"S Sutehall","year":"2022","unstructured":"Sutehall S, Muniz-Pardos B, Bosch AN, Galloway SD, Pitsiladis Y. The impact of sodium alginate hydrogel on exogenous glucose oxidation rate and gastrointestinal comfort in well-trained runners. Front Nutr. 2022;8:810041. https:\/\/doi.org\/10.3389\/fnut.2021.810041.","journal-title":"Front Nutr"},{"key":"2462_CR91","doi-asserted-by":"publisher","first-page":"E708","DOI":"10.1152\/ajpendo.00357.2005","volume":"290","author":"GA Wallis","year":"2006","unstructured":"Wallis GA, Dawson R, Achten J, Webber J, Jeukendrup AE. Metabolic response to carbohydrate ingestion during exercise in males and females. Am J Physiol Endocrinol Metab. 2006;290:E708\u201315. https:\/\/doi.org\/10.1152\/ajpendo.00357.2005.","journal-title":"Am J Physiol Endocrinol Metab"}],"container-title":["Sports Medicine"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1007\/s40279-026-02462-z.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/article\/10.1007\/s40279-026-02462-z","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1007\/s40279-026-02462-z.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,9,25]],"date-time":"2026-09-25T13:53:42Z","timestamp":1790344422000},"score":1,"resource":{"primary":{"URL":"https:\/\/link.springer.com\/10.1007\/s40279-026-02462-z"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,6,8]]},"references-count":91,"journal-issue":{"issue":"10","published-print":{"date-parts":[[2026,10]]}},"alternative-id":["2462"],"URL":"https:\/\/doi.org\/10.1007\/s40279-026-02462-z","relation":{},"ISSN":["0112-1642","1179-2035"],"issn-type":[{"value":"0112-1642","type":"print"},{"value":"1179-2035","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,6,8]]},"assertion":[{"value":"4 May 2026","order":1,"name":"accepted","label":"Accepted","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"8 June 2026","order":2,"name":"first_online","label":"First Online","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"Paul Booth, Taj Krieger and Dr Ed Maunder declare no competing interests. Dr Daniel Plews declares a professional affiliation as Head of Research for Pillar Performance, a micronutrition company with no presently commercial interest in carbohydrate fuelling products.","order":1,"name":"Ethics","label":"Competing Interests","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"This research received no specific grant from any funding agency in the public, commercial or not-for-profit sectors.","order":2,"name":"Ethics","label":"Funding","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"Not applicable. This manuscript is a current opinion piece and did not involve the collection of primary data.","order":3,"name":"Ethics","label":"Ethics Approval","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"No new data were generated for this manuscript. All data shown in Figs.\n                      \n                      and\n                      \n                      were extracted from previously published studies, the full details of which are provided in the manuscript references. All other content represents a narrative synthesis of existing literature, and no primary data were collected or analysed.","order":4,"name":"Ethics","label":"Availability of Data and Materials","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"D.P. conceived the primary concepts of the manuscript, led the writing and preparation of the manuscript and takes overall responsibility for the integrity of the work. E.M. contributed to the original conceptualization of the manuscript and aided in critical revisions. P.B. made significant contributions to the literature review, particularly regarding ultra-endurance running and emerging evidence around ultra-high carbohydrate fuelling and performance. T.K. contributed to the data analysis shown in Fig.\u00a0\n                      \n                      , the formulation of Table\u00a0\n                      \n                      , and the collection and organization of the associated data. All authors contributed to the interpretation of the literature, critically revised the manuscript for important intellectual content and approved the final version submitted for publication.","order":5,"name":"Ethics","label":"Authors\u2019 Contributions","group":{"name":"EthicsHeading","label":"Declarations"}}]}}