Oral fructose intake does not improve exercise, visual, or cognitive performance during acute normobaric hypoxia in healthy humans

Frontiers in Nutrition, vol. 10, pp. 1170873

Abstract

Introduction The ability to metabolize fructose to bypass the glucose pathway in near-anaerobic conditions appears to contribute to the extreme hypoxia tolerance of the naked-mole rats. Therefore, we hypothesized that exogenous fructose could improve endurance capacity and cognitive performance in humans exposed to hypoxia. Methods In a randomized, double-blind, crossover study, 26 healthy adults (9 women, 17 men; 28.8 ± 8.1 (SD) years) ingested 75 g fructose, 82.5 g glucose, or placebo during acute hypoxia exposure (13% oxygen in a normobaric hypoxia chamber, corresponding to oxygen partial pressure at altitude of ~3,800 m) on separate days. We measured exercise duration, heart rate, SpO2, blood gasses, and perceived exertion during a 30-min incremental load test followed by Farnsworth-Munsell 100 Hue (FM-100) color vision testing and the unstable tracking task (UTT) to probe eye-hand coordination performance. Results Exercise duration in hypoxia was 21.13 ± 0.29 (SEM) min on fructose, 21.35 ± 0.29 min on glucose, and 21.35 ± 0.29 min on placebo (p = 0.86). Heart rate responses and perceived exertion did not differ between treatments. Total error score (TES) during the FM-100 was 47.1 ± 8.0 on fructose, 45.6 ± 7.6 on glucose and 53.3 ± 9.6 on placebo (p = 0.35) and root mean square error (RMSE) during the UTT was 15.1 ± 1.0, 15.1 ± 1.0 and 15.3 ± 0.9 (p = 0.87). Discussion We conclude that oral fructose intake in non-acclimatized healthy humans does not acutely improve exercise performance and cognitive performance during moderate hypoxia. Thus, hypoxia tolerance in naked mole-rats resulting from oxygen-conserving fructose utilization, cannot be easily reproduced in humans.

Authors 14

1. Titiaan E. Post Aachen Centre for Human Drug Research (CHDR)

   Deutsches Zentrum für Luft- und Raumfahrt e. V. (DLR) · Centre for Human Drug Research

   Affiliation as printed

   Centre for Human Drug Research (CHDR), Leiden, Netherlands

   Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany

2. Jan Schmitz

   University of Cologne · Deutsches Zentrum für Luft- und Raumfahrt e. V. (DLR) · University Hospital Cologne

   Affiliation as printed

   Department of Anesthesiology and Intensive Care Medicine, Faculty of Medicine and University Hospital of Cologne, University of Cologne, Cologne, Germany

   Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany

3. Cayla Denney

   Deutsches Zentrum für Luft- und Raumfahrt e. V. (DLR)

   Affiliation as printed

   Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany

4. Riccardo De Gioannis

   University of Cologne · Deutsches Zentrum für Luft- und Raumfahrt e. V. (DLR) · University Hospital Cologne

   Affiliation as printed

   Department III for Internal Medicine, Faculty of Medicine, Heart Center, University Hospital of Cologne, Cologne, Germany

   Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany

5. Henning Weis

   University of Cologne · Deutsches Zentrum für Luft- und Raumfahrt e. V. (DLR) · University Hospital Cologne

   Affiliation as printed

   Department of Nuclear Medicine, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany

   Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany

6. Dominik Hans Pesta

   University of Cologne · Deutsches Zentrum für Luft- und Raumfahrt e. V. (DLR) · Cologne Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases · University Hospital Cologne

   Affiliation as printed

   Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany

   Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany

   Center for Endocrinology, Diabetes and Preventive Medicine (CEDP), University Hospital Cologne, Cologne, Germany

7. Andreas Peter

   Universitätsklinikum Tübingen · German Center for Diabetes Research · University of Tübingen

   Affiliation as printed

   Department for Diagnostic Laboratory Medicine, Institute for Clinical Chemistry and Pathobiochemistry, University Hospital Tübingen, Tübingen, Germany

   German Center for Diabetes Research (DZD), Neuherberg, Germany

   Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tübingen, Tübingen, Germany

8. Andreas L. Birkenfeld

   German Center for Diabetes Research · University of Tübingen

   Affiliation as printed

   Division of Diabetology, Endocrinology, and Nephrology, Department of Internal Medicine, Eberhard Karls University Tübingen, Tübingen, Germany

   German Center for Diabetes Research (DZD), Neuherberg, Germany

   Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tübingen, Tübingen, Germany

9. Sven Haufe

   Medizinische Hochschule Hannover

   Affiliation as printed

   Clinic for Rehabilitation and Sports Medicine, Hannover Medical School, Hannover, Germany

10. Uwe Tegtbur

    Medizinische Hochschule Hannover

    Affiliation as printed

    Clinic for Rehabilitation and Sports Medicine, Hannover Medical School, Hannover, Germany

11. Petra Frings‐Meuthen

    Deutsches Zentrum für Luft- und Raumfahrt e. V. (DLR)

    Affiliation as printed

    Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany

12. Ann C. Ewald

    Deutsches Zentrum für Luft- und Raumfahrt e. V. (DLR)

    Affiliation as printed

    Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany

13. Daniel Aeschbach

    University of Bonn · Deutsches Zentrum für Luft- und Raumfahrt e. V. (DLR)

    Affiliation as printed

    Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany

    Institute of Experimental Epileptology and Cognition Research, University of Bonn Medical Center, Bonn, Germany

14. Jens Jordan corresponding

    University of Cologne · Deutsches Zentrum für Luft- und Raumfahrt e. V. (DLR)

    Affiliation as printed

    Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany

    Medical Faculty, University of Cologne, Cologne, Germany