Respiratory Exchange Ratio

    Last Updated: October 13, 2024

    Respiratory exchange ratio (RER) is the ratio between carbon dioxide production and oxygen uptake used to determine whether fat or carbohydrate is predominantly used for energy (e.g., RER of 0.7 indicates that fat is the primary fuel source, while 1.0 indicates carbohydrate).

    1,380 participants in 17 trials

    Examine Database: Respiratory Exchange Ratio

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    Examine Database References

    1. L-Carnitine - A C Gimenes, D M Bravo, L M Nápolis, M T Mello, A S B Oliveira, J A Neder, L E NeryEffect of L-carnitine on exercise performance in patients with mitochondrial myopathyBraz J Med Biol Res.(2015 Apr)
    2. L-Carnitine - E P Brass, C L Hoppel, W R HiattEffect of intravenous L-carnitine on carnitine homeostasis and fuel metabolism during exercise in humansClin Pharmacol Ther.(1994 Jun)
    3. Ketogenic Diet - Parker N Hyde, Teryn N Sapper, Christopher D Crabtree, Richard A LaFountain, Madison L Bowling, Alex Buga, Brandon Fell, Fionn T McSwiney, Ryan M Dickerson, Vincent J Miller, Debbie Scandling, Orlando P Simonetti, Stephen D Phinney, William J Kraemer, Sarah A King, Ronald M Krauss, Jeff S VolekDietary carbohydrate restriction improves metabolic syndrome independent of weight lossJCI Insight.(2019 Jun 20)
    4. L-Carnitine - C Greig, K M Finch, D A Jones, M Cooper, A J Sargeant, C A ForteThe effect of oral supplementation with L-carnitine on maximum and submaximum exercise capacityEur J Appl Physiol Occup Physiol.(1987)
    5. Astaxanthin - Res PT, Cermak NM, Stinkens R, Tollakson TJ, Haenen GR, Bast A, Van Loon LJAstaxanthin supplementation does not augment fat use or improve endurance performanceMed Sci Sports Exerc.(2013 Jun)
    6. Panax Ginseng (Korean Ginseng) - H J Engels, J C WirthNo ergogenic effects of ginseng (Panax ginseng C.A. Meyer) during graded maximal aerobic exerciseJ Am Diet Assoc.(1997 Oct)
    7. Spirulina - Tom Gurney, Owen SpendiffSpirulina supplementation improves oxygen uptake in arm cycling exerciseEur J Appl Physiol.(2020 Dec)
    8. Iron - Brownlie T 4th, Utermohlen V, Hinton PS, Giordano C, Haas JDMarginal iron deficiency without anemia impairs aerobic adaptation among previously untrained womenAm J Clin Nutr.(2002 Apr)
    9. L-Carnitine - Yvonne M H Bruls, Yvo J M Op den Kamp, Esther Phielix, Lucas Lindeboom, Bas Havekes, Gert Schaart, Esther Moonen-Kornips, Joachim E Wildberger, Matthijs K C Hesselink, Patrick Schrauwen, Vera B Schrauwen-HinderlingL-carnitine infusion does not alleviate lipid-induced insulin resistance and metabolic inflexibilityPLoS One.(2020 Sep 25)
    10. L-Carnitine - Weronika N Abramowicz, Stuart D R GallowayEffects of acute versus chronic L-carnitine L-tartrate supplementation on metabolic responses to steady state exercise in males and femalesInt J Sport Nutr Exerc Metab.(2005 Aug)
    11. Tart Cherry Juice - Desai T, Roberts M, Bottoms LEffects of short-term continuous Montmorency tart cherry juice supplementation in participants with metabolic syndrome.Eur J Nutr.(2021-Apr)
    12. Tart Cherry Juice - Desai T, Bottoms L, Roberts MThe effects of Montmorency tart cherry juice supplementation and FATMAX exercise on fat oxidation rates and cardio-metabolic markers in healthy humans.Eur J Appl Physiol.(2018-Dec)
    13. Tart Cherry Juice - Lear R, O'Leary M, O'Brien Andersen L, Holt CC, Stensvold CR, van der Giezen M, Bowtell JLTart Cherry Concentrate Does Not Alter the Gut Microbiome, Glycaemic Control or Systemic Inflammation in a Middle-Aged Population.Nutrients.(2019-May-13)
    14. Whey Protein - Lam FC, Bukhsh A, Rehman H, Waqas MK, Shahid N, Khaliel AM, Elhanish A, Karoud M, Telb A, Khan TMEfficacy and Safety of Whey Protein Supplements on Vital Sign and Physical Performance Among Athletes: A Network Meta-Analysis.Front Pharmacol.(2019 Apr 24)
    15. Caffeine - Glaister M, Gissane CCaffeine and Physiological Responses to Submaximal Exercise: A Meta-AnalysisInt J Sports Physiol Perform.(2017 Sep 5)
    16. Medium-chain Triglycerides - Effect of Continuous Ingestion of 2 g of Medium-Chain Triglycerides on Substrate Metabolism during Low-Intensity Physical Activity .()
    17. Aerobic Exercise - Kazeminasab F, Rafiee P, Miraghajani M, Santos HO, Symonds ME, Rosenkranz SKThe effects of acute bouts of exercise in fasted vs. fed states on glucose and lipid metabolism in healthy adults: A systematic review and meta-analysis of randomized clinical trials.Clin Nutr ESPEN.(2025 Feb 5)