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dc.contributor.authorRamírez Maldonado, Mauricio
dc.contributor.authorJurado Fasoli, Lucas 
dc.contributor.authorDel Coso, Juan
dc.contributor.authorRojas Ruiz, Jonatan
dc.contributor.authorAmaro Gahete, Francisco José
dc.identifier.citationRamírez-Maldonado, M., Jurado-Fasoli, L., del Coso, J. et al. Caffeine increases maximal fat oxidation during a graded exercise test: is there a diurnal variation?. J Int Soc Sports Nutr 18, 5 (2021).
dc.description.abstractBackground: There is evidence that caffeine increases the maximal fat oxidation rate (MFO) and aerobic capacity, which are known to be lower in the morning than in the afternoon. This paper examines the effect of caffeine intake on the diurnal variation of MFO during a graded exercise test in active men. Methods: Using a triple-blind, placebo-controlled, crossover experimental design, 15 active caffeine-naïve men (age: 32 ± 7 years) completed a graded exercise test four times at seven-day intervals. The subjects ingested 3 mg/ kg of caffeine or a placebo at 8 am in the morning and 5 pm in the afternoon (each subject completed tests under all four conditions in a random order). A graded cycling test was performed. MFO and maximum oxygen uptake (VO2max) were measured by indirect calorimetry, and the intensity of exercise that elicited MFO (Fatmax) calculated. Results: MFO, Fatmax and VO2max were significantly higher in the afternoon than in the morning (all P < 0.05). Compared to the placebo, caffeine increased mean MFO by 10.7% (0.28 ± 0.10 vs. 0.31 ± 0.09 g/min respectively, P < 0.001) in the morning, and by a mean 29.0% (0.31 ± 0.09 vs. 0.40 ± 0.10 g/min, P < 0.001) in the afternoon. Caffeine also increased mean Fatmax by 11.1% (36.9 ± 14.4 [placebo] vs. 41.0 ± 13.1%, P = 0.005) in the morning, and by 13.1% (42.0 ± 11.6 vs. 47.5 ± 10.8%, P = 0.008) in the afternoon. Conclusion: These findings confirm the previously reported diurnal variation in the whole-body fat oxidation rate during graded exercise in active caffeine-naïve men, and indicate that the acute ingestion of 3 mg/kg of caffeine increases MFO, Fatmax and VO2max independent of the time of day. Trial registration: NCT04320446. Registered 25 March 2020 - Retrospectively registered.es_ES
dc.description.sponsorshipUniversity of Granada Plan Propio de Investigacion 2016-Excellence actions: Unit of Excellence on Exercise and Health (UCEES)es_ES
dc.description.sponsorshipJunta de Andalucia, Consejeria de Conocimiento, Investigacion y Universidades (ERDF) SOMM17/6107/UGRes_ES
dc.rightsAtribución 3.0 España*
dc.subjectExercise performancees_ES
dc.subjectBody compositiones_ES
dc.subjectNutrition es_ES
dc.subjectBody weightes_ES
dc.subjectDietary supplements es_ES
dc.titleCaffeine increases maximal fat oxidation during a graded exercise test: is there a diurnal variation?es_ES

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Atribución 3.0 España
Except where otherwise noted, this item's license is described as Atribución 3.0 España