Caffeine increases whole-body fat oxidation during 1 h of cycling at Fatmax



The ergogenic effect of caffeine on exercise of maximum intensity has been well established. However, there is controversy regarding the effect of caffeine on shifting substrate oxidation at submaximal exercise. The aim of this study was to investigate the effect of acute caffeine ingestion on whole-body substrate oxidation during 1 h of cycling at the intensity that elicits maximal fat oxidation (Fatmax).


In a double-blind, randomized, and counterbalanced experiment, 12 healthy participants (VO2max = 50.7 ± 12.1 mL/kg/min) performed two acute experimental trials after ingesting either caffeine (3 mg/kg) or a placebo (cellulose). The trials consisted of 1 h of continuous cycling at Fatmax. Energy expenditure, fat oxidation rate, and carbohydrate oxidation rate were continuously measured by indirect calorimetry.


In comparison to the placebo, caffeine increased the amount of fat oxidized during the trial (19.4 ± 7.7 vs 24.7 ± 9.6 g, respectively; P = 0.04) and decreased the amount of carbohydrate oxidized (94.6 ± 30.9 vs 73.8 ± 32.4 g; P = 0.01) and the mean self-perception of fatigue (Borg scale = 11 ± 2 vs 10 ± 2 arbitrary units; P = 0.05). In contrast, caffeine did not modify total energy expenditure (placebo = 543 ± 175; caffeine = 559 ± 170 kcal; P = 0.60) or mean heart rate (125 ± 13 and 127 ± 9 beats/min; P = 0.30) during exercise. Before exercise, caffeine increased systolic and diastolic blood pressure whilst it increased the feelings of nervousness and vigour after exercise (P < 0.05).


These results suggest that a moderate dose of caffeine (3 mg/kg) increases the amount of fat oxidized during 1 h of cycling at Fatmax. Thus, caffeine might be used as an effective strategy to enhance body fat utilization during submaximal exercise. The occurrence of several side effects should be taken into account when using caffeine to reduce body fat in populations with hypertension or high sensitivity to caffeine.

This is a preview of subscription content, access via your institution.

Fig. 1
Fig. 2


  1. 1.

    Goldstein ER, Ziegenfuss T, Kalman D et al (2010) International society of sports nutrition position stand: Caffeine and performance. J Int Soc Sports Nutr 7:5

    Article  Google Scholar 

  2. 2.

    Salinero J, Lara B, Del Coso J (2019) Effects of acute ingestion of caffeine on team sports performance: a systematic review and meta-analysis. Res Sport Med 27:238–256.

    Article  Google Scholar 

  3. 3.

    Grgic J, Grgic I, Pickering C et al (2019) Wake up and smell the coffee: Caffeine supplementation and exercise performance - An umbrella review of 21 published meta-analyses. Br J Sports Med 54:681–688.

    Article  PubMed  Google Scholar 

  4. 4.

    Maughan RJ, Burke LM, Dvorak J et al (2018) IOC consensus statement: dietary supplements and the high-performance athlete. Br J Sports Med 52:439–455.

    Article  PubMed  PubMed Central  Google Scholar 

  5. 5.

    Fredholm BB, Yang J, Wang Y (2017) Low, but not high, dose caffeine is a readily available probe for adenosine actions. Mol Aspects Med 55:20–25

    CAS  Article  Google Scholar 

  6. 6.

    Graham TE (2001) Caffeine and exercise metabolism, endurance and performance. Sport Med 31:785–807

    CAS  Article  Google Scholar 

  7. 7.

    Davis JK, Green JM (2009) Caffeine and anaerobic performance: Ergogenic value and mechanisms of action. Sport Med 39:813–832

    CAS  Article  Google Scholar 

  8. 8.

    Ruíz-Moreno C, Lara B, Brito de Souza D et al (2020) Acute caffeine intake increases muscle oxygen saturation during a maximal incremental exercise test. Br J Clin Pharmacol 86:861–867.

    CAS  Article  PubMed  PubMed Central  Google Scholar 

  9. 9.

    Gutiérrez-Hellín J, Del Coso J (2018) Effects of p-Synephrine and caffeine ingestion on substrate oxidation during exercise. Med Sci Sport Exerc 50:1899–1906.

    CAS  Article  Google Scholar 

  10. 10.

    Costill DL, Dalsky GP, Fink WJ (1978) Effects of caffeine ingestion on metabolism and exercise performance. Med Sci Sports 10:155–158

    CAS  PubMed  Google Scholar 

  11. 11.

    Venables MC, Achten J, Jeukendrup AE (2005) Determinants of fat oxidation during exercise in healthy men and women: A cross-sectional study. J Appl Physiol.

    Article  PubMed  Google Scholar 

  12. 12.

    Graham TE, Helge JW, MacLean DA et al (2000) Caffeine ingestion does not alter carbohydrate or fat metabolism in human skeletal muscle during exercise. J Physiol 529:837–847.

    CAS  Article  PubMed  PubMed Central  Google Scholar 

  13. 13.

    Graham TE, Battram DS, Dela F et al (2008) Does caffeine alter muscle carbohydrate and fat metabolism during exercise? Appl Physiol Nutr Metab Physiol Appl Nutr Metab 33:1311–1318.

    CAS  Article  Google Scholar 

  14. 14.

    Graham TE, Spriet LL (1995) Metabolic, catecholamine, and exercise performance responses to various doses of caffeine. J Appl Physiol 78:867–874.

    CAS  Article  PubMed  Google Scholar 

  15. 15.

    Beaumont RE, James LJ (2017) Effect of a moderate caffeine dose on endurance cycle performance and thermoregulation during prolonged exercise in the heat. J Sci Med Sport 20:1024–1028.

    Article  PubMed  Google Scholar 

  16. 16.

    Hodgson AB, Randell RK, Jeukendrup AE (2013) The metabolic and performance effects of caffeine compared to coffee during endurance exercise. PLoS ONE 8:e59561.

    CAS  Article  PubMed  PubMed Central  Google Scholar 

  17. 17.

    Anderson DE, Hickey MS (1994) Effects of caffeine on the metabolic and catecholamine responses to exercise in 5 and 28 degrees C. Med Sci Sports Exerc 26:453–458

    CAS  Article  Google Scholar 

  18. 18.

    Ryu S, Choi SK, Joung SS et al (2001) Caffeine as a lipolytic food component increases endurance performance in rats and athletes. J Nutr Sci Vitaminol (Tokyo) 47:139–146.

    CAS  Article  Google Scholar 

  19. 19.

    Donelly K, McNaughton L (1992) The effects of two levels of caffeine ingestion on excess postexercise oxygen consumption in untrained women. Eur J Appl Physiol Occup Physiol 65:459–463.

    CAS  Article  PubMed  Google Scholar 

  20. 20.

    Schubert MM, Sabapathy S, Leveritt M, Desbrow B (2014) Acute exercise and hormones related to appetite regulation: a meta-analysis. Sports Med 44:387–403.

    Article  PubMed  Google Scholar 

  21. 21.

    Alkhatib A, Seijo M, Larumbe E, Naclerio F (2015) Acute effectiveness of a “fat-loss” product on substrate utilization, perception of hunger, mood state and rate of perceived exertion at rest and during exercise. J Int Soc Sports Nutr 12:44.

    CAS  Article  PubMed  PubMed Central  Google Scholar 

  22. 22.

    Cruz R, de Aguiar R, Turnes T et al (2015) Caffeine affects time to exhaustion and substrate oxidation during cycling at maximal lactate steady state. Nutrients 7:5254–5264.

    CAS  Article  PubMed  Google Scholar 

  23. 23.

    Maunder E, Plews DJ, Kilding AE (2018) Contextualising maximal fat oxidation during exercise: Determinants and normative values. Front Physiol 23:599.

    Article  Google Scholar 

  24. 24.

    Gutiérrez-Hellín J, Ruiz-Moreno C, Del Coso J (2019) Acute p-synephrine ingestion increases whole-body fat oxidation during 1-h of cycling at Fatmax. Eur J Nutr.

    Article  PubMed  Google Scholar 

  25. 25.

    Filip A, Wilk M, Krzysztofik M, Del Coso J (2020) Inconsistency in the ergogenic effect of caffeine in athletes who regularly consume caffeine: Is it due to the disparity in the criteria that defines habitual caffeine intake? Nutrients.

    Article  PubMed  PubMed Central  Google Scholar 

  26. 26.

    Frandsen J, Pistoljevic N, Quesada JP et al (2020) Menstrual cycle phase does not affect whole body peak fat oxidation rate during a graded exercise test. J Appl Physiol 128:681–687.

    CAS  Article  PubMed  Google Scholar 

  27. 27.

    Horton TJ, Miller EK, Glueck D, Tench K (2002) No effect of menstrual cycle phase on glucose kinetics and fuel oxidation during moderate-intensity exercise. Am J Physiol - Endocrinol Metab.

    Article  PubMed  PubMed Central  Google Scholar 

  28. 28.

    Lara B, Gutiérrez-Hellín J, García-Bataller A et al (2019) Ergogenic effects of caffeine on peak aerobic cycling power during the menstrual cycle. Eur J Nutr.

    Article  PubMed  Google Scholar 

  29. 29.

    Lara B, Gutiérrez Hellín J, Ruíz-Moreno C et al (2019) Acute caffeine intake increases performance in the 15-s Wingate test during the menstrual cycle. Br J Clin Pharmacol.

    Article  Google Scholar 

  30. 30.

    Burke LM, Hawley JA, Wong SHS, Jeukendrup AE (2011) Carbohydrates for training and competition. J Sports Sci 29:S17–S27.

    Article  PubMed  Google Scholar 

  31. 31.

    Sawka MN, Burke LM, Eichner ER et al (2007) Exercise and fluid replacement. Med Sci Sports Exerc 39:377–390

    Article  Google Scholar 

  32. 32.

    Brouwer E (1957) On simple formulae for calculating the heat expenditure and the quantities of carbohydrate and fat oxidized in metabolism of men and animals, from gaseous exchange (Oxygen intake and carbonic acid output) and urine-N. Acta Physiol Pharmacol Neerl 6:795–802

    CAS  PubMed  Google Scholar 

  33. 33.

    Borg GAV (1954) Psychophysical bases of perceived exertion. Plast Reconstr Surg 14:377–381.

    Article  Google Scholar 

  34. 34.

    Salinero JJ, Lara B, Abian-Vicen J et al (2014) The use of energy drinks in sport: Perceived ergogenicity and side effects in male and female athletes. Br J Nutr 112:1494–1502.

    CAS  Article  PubMed  Google Scholar 

  35. 35.

    Lara B, Ruiz-Vicente D, Areces F et al (2015) Acute consumption of a caffeinated energy drink enhances aspects of performance in sprint swimmers. Br J Nutr 114:908–914.

    CAS  Article  PubMed  Google Scholar 

  36. 36.

    Hopkins WG, Marshall SW, Batterham AM, Hanin J (2009) Progressive statistics for studies in sports medicine and exercise science. Med Sci Sports Exerc 41:3–13.

    Article  PubMed  Google Scholar 

  37. 37.

    Hopkins WG (2020) A Spreadsheet for deriving a confidence interval, mechanistic inference and clinical inference from a p value. Accessed 20 Jun 2020

  38. 38.

    McCall AL, Millington WR, Wurtman RJ (1982) Blood-brain barrier transport of caffeine: Dose-related restriction of adenine transport. Life Sci 31:2709–2715.

    CAS  Article  PubMed  Google Scholar 

  39. 39.

    Purdom T, Kravitz L, Dokladny K, Mermier C (2018) Understanding the factors that effect maximal fat oxidation. J Int Soc Sports Nutr 15:3.

    CAS  Article  PubMed  PubMed Central  Google Scholar 

  40. 40.

    Randell RK, Rollo I, Roberts TJ et al (2017) Maximal fat oxidation rates in an athletic population. Med Sci Sports Exerc 49:133–140.

    CAS  Article  PubMed  Google Scholar 

  41. 41.

    Daly J, Shi D (1994) The role of adenosine receptors in the central action of caffeine. Pharmacopsychoecologia 7:201–213.

    Article  PubMed  PubMed Central  Google Scholar 

  42. 42.

    Killen LG, Green JM, O’Neal EK et al (2013) Effects of caffeine on session ratings of perceived exertion. Eur J Appl Physiol 113:721–727.

    CAS  Article  PubMed  Google Scholar 

  43. 43.

    Doherty M, Smith PM (2005) Effects of caffeine ingestion on rating of perceived exertion during and after exercise: a meta-analysis. Scand J Med Sci Sports 15:69–78.

    CAS  Article  PubMed  Google Scholar 

  44. 44.

    Ruiz-Moreno C, Lara B, Salinero JJ et al (2020) Time course of tolerance to adverse effects associated with the ingestion of a moderate dose of caffeine. Eur J Nutr.

    Article  PubMed  Google Scholar 

  45. 45.

    Lara B, Gonzalez-Millán C, Salinero JJ et al (2014) Caffeine-containing energy drink improves physical performance in female soccer players. Amino Acids 46:1385–1392.

    CAS  Article  PubMed  Google Scholar 

  46. 46.

    Lara B, Ruiz-Moreno C, Salinero JJ, Del Coso J (2019) Time course of tolerance to the performance benefits of caffeine. PLoS ONE 14:e0210275.

    CAS  Article  PubMed  PubMed Central  Google Scholar 

Download references


The authors wish to thank the subjects for their invaluable contribution to the study.


This investigation did not receive any funding.

Author information



Corresponding author

Correspondence to Juan Del Coso.

Ethics declarations

Conflict of interest

The authors declare no support from any organization for the submitted work; no financial relationships with any organizations that might have an interest in the submitted work in the previous 3 years; and no other relationships or activities that could appear to have influenced the submitted work.

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Ruiz-Moreno, C., Gutiérrez-Hellín, J., Amaro-Gahete, F.J. et al. Caffeine increases whole-body fat oxidation during 1 h of cycling at Fatmax. Eur J Nutr 60, 2077–2085 (2021).

Download citation


  • Endurance exercise
  • Substrate oxidation
  • Adverse effects
  • Stimulant
  • Performance