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Sports Medicine

, Volume 48, Issue 8, pp 1913–1928 | Cite as

The Effect of Acute Caffeine Ingestion on Endurance Performance: A Systematic Review and Meta–Analysis

  • Kyle Southward
  • Kay J. Rutherfurd-Markwick
  • Ajmol Ali
Systematic Review

Abstract

Background

Caffeine is a widely used ergogenic aid with most research suggesting it confers the greatest effects during endurance activities. Despite the growing body of literature around the use of caffeine as an ergogenic aid, there are few recent meta-analyses that quantitatively assess the effect of caffeine on endurance exercise.

Objectives

To summarise studies that have investigated the ergogenic effects of caffeine on endurance time-trial performance and to quantitatively analyse the results of these studies to gain a better understanding of the magnitude of the ergogenic effect of caffeine on endurance time-trial performance.

Methods

A systematic review was carried out on randomised placebo-controlled studies investigating the effects of caffeine on endurance performance and a meta-analysis was conducted to determine the ergogenic effect of caffeine on endurance time-trial performance.

Results

Forty-six studies met the inclusion criteria and were included in the meta-analysis. Caffeine has a small but evident effect on endurance performance when taken in moderate doses (3–6 mg/kg) as well as an overall improvement following caffeine compared to placebo in mean power output (3.03 ± 3.07%; effect size = 0.23 ± 0.15) and time-trial completion time (2.22 ± 2.59%; effect size = 0.41 ± 0.2). However, differences in responses to caffeine ingestion have been shown, with two studies reporting slower time-trial performance, while five studies reported lower mean power output during the time–trial.

Conclusion

Caffeine can be used effectively as an ergogenic aid when taken in moderate doses, such as during sports when a small increase in endurance performance can lead to significant differences in placements as athletes are often separated by small margins.

Notes

Acknowledgements

The present article presents material that has not been submitted for publication elsewhere. The authors declare no conflict of interest.

Compliance with Ethical Standards

Funding

No funding was received for this work.

Conflict of interests

The authors Kyle Southward, Ajmol Ali, and Kay Rutherfurd-Markwick declare that they have no competing interests to declare in relation to this manuscript.

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Copyright information

© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  1. 1.School of Sport, Exercise and NutritionMassey UniversityAucklandNew Zealand
  2. 2.School of Health SciencesMassey UniversityAucklandNew Zealand
  3. 3.Centre for Metabolic Health Research, Massey UniversityAucklandNew Zealand

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