Tehran University of Medical Sciences Iranian Journal of Public Health 2251-6085 54 4 2025 04 01 723 738 Zahra Gohari Dezfuli 1. Sports Medicine Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran 2. Department of Clinical Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences, Tehran, Iran Minoo Hasan Rashedi 1. Sports Medicine Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran 2. Department of Nutrition, School of Public Health, Iran University of Medical Sciences, Tehran, Iran Fatemeh Naeini Department of Clinical Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences, Tehran, Iran Sakineh Shab-Bidar Department of Community Nutrition, School of Nutritional Science and Dietetics, Tehran University of Medical Sciences, Tehran, Iran Mohammadhossein Pourgharib-Shahi Sports Medicine Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran Xueying Zhang Shenzhen Key Laboratory of Metabolic Health, Center for Energy Metabolism and Reproduction, Shenzhen Institutes of Ad-vanced Technology, Chinese Academy of Sciences, Shenzhen, China Elaheh Dehghani 1. Sports Medicine Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran 2. Department of Clinical Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences, Tehran, Iran Kurosh Djafarian 1. Sports Medicine Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran 2. Department of Clinical Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences, Tehran, Iran 2024 08 27 2024 11 11 Background: Numerous studies have aimed to compare the effects of glucose (Glu) consumption with those of glucose-fructose (Glu-Fru) consumption on oxidation rates during exercise. However, divergent outcomes have surfaced due to variations in exercise protocols and concurrent substance ingestion, leading to a lack of consensus. This systematic review and meta-analysis investigated the comparative effects of Glu and Glu-Fru on total carbohydrate oxidation, endogenous carbohydrate oxidation, exogenous carbohydrate oxidation, and total fat oxidation rates during exercise. Methods: A systematic search of PubMed, Scopus, and Web of Science databases up to February 2023.  The search yielded 14 randomized controlled trials involving 125 endurance athletes. Results: The meta-analyses revealed that Glu supplementation significantly increased total carbohydrate oxidation (WMD: 0.21 g/min) compared to Glu-Fru. Endogenous carbohydrate oxidation significantly increased with Glu (WMD: -0.12), while Glu-Fru led to increased exogenous carbohydrate oxidation (WMD: 0.27 g/min). Total fat oxidation decr eased with Glu-Fru (WMD: -0.06 g/min). Conclusion: By investigating athletic nutrition complexities, our findings shed light on metabolic responses to Glu-Fru versus Glu supplementation. Tailoring hydration strategies, athletes should select an optimal Glu-Fru to Glu ratio for maximal oxidation and enhanced performance. Future research could explore dose-response relationships for optimal metabolic benefits during exercise. https://ijph.tums.ac.ir/index.php/ijph/article/view/36484 https://ijph.tums.ac.ir/index.php/ijph/article/download/36484/8514