Carbohydrate Ingestion During Prolonged Exercise Blunts the Reduction in Power Output at the Moderate-to-Heavy Intensity Transition

Dudley-Rode, HZinn, CPlews, DJCharoensap, TMaunder, E2026-05-182026-05-182024-12-24European Journal of Applied Physiology, ISSN: 1439-6319 (Print); 1439-6327 (Online), Springer Science and Business Media LLC, 125(5), 1349-1359. doi: 10.1007/s00421-024-05687-w1439-63191439-6327http://hdl.handle.net/10292/21104Purpose: To determine the effect of carbohydrate ingestion during prolonged exercise on durability of the moderate-to-heavy-intensity transition and severe-intensity performance. Methods: Twelve trained cyclists and triathletes (10 males, 2 females; V˙O2peak, 59 ± 5 mL kg−1 min−1; training volume, 14 ± 5 h week−1) performed an incremental test and 5-min time trial (TT) without prior exercise (PRE), and after 150 min of moderate-intensity cycling, with (POSTCHO) and without (POSTCON) carbohydrate ingestion. Results: Power output at the first ventilatory threshold (VT1) was lower in POSTCHO (225 ± 36 W, ∆ -3 ± 2%, P = 0.027, n = 11) and POSTCON (216 ± 35 W, ∆ -6 ± 4%, P = 0.001, n = 12) than PRE (229 ± 37 W, n = 12), and lower in POSTCON than POSTCHO (∆ -7 ± 9 W, ∆ -3 ± 4%, P = 0.019). Mean power output in the 5-min TT was lower in POSTCHO (351 ± 53 W, ∆ -4 ± 3%, P = 0.025) and POSTCON (328 ± 63 W, ∆ -10 ± 10%, P = 0.027) than PRE (363 ± 55 W), but POSTCHO and POSTCON were not significantly different (∆ 25 ± 37 W, ∆ 9 ± 13%, P = 0.186). Blood glucose concentration was maintained in POSTCHO, and was significantly lower at the 120 and 150-min timepoint in POSTCON (P < 0.05). Conclusion: These data suggest that durability of the moderate-to-heavy-intensity transition is improved with carbohydrate ingestion. This has implications for training programming and load monitoring.Free access courtesy of Springer. Some rights reserved (see Journal article file for details).CarbohydrateDurabilityExerciseNutrition42 Health Sciences4207 Sports Science and Exercise1106 Human Movement and Sports SciencesSport Sciences3202 Clinical sciences3208 Medical physiology4207 Sports science and exerciseHumansMaleDietary CarbohydratesFemaleAdultExerciseOxygen ConsumptionBicyclingPhysical EnduranceAthletic PerformanceHumansDietary CarbohydratesExerciseOxygen ConsumptionPhysical EnduranceBicyclingAdultFemaleMaleAthletic PerformanceHumansMaleDietary CarbohydratesFemaleAdultExerciseOxygen ConsumptionBicyclingPhysical EnduranceAthletic PerformanceCarbohydrate Ingestion During Prolonged Exercise Blunts the Reduction in Power Output at the Moderate-to-Heavy Intensity TransitionJournal ArticleOpenAccess10.1007/s00421-024-05687-w