A range of expert opinions capture the scope of this ongoing debate in an informative roundtable discussion published in Journal of Caffeine Research, a quarterly peer-reviewed journal from Mary Ann Liebert, Inc.
Led by Journal of Caffeine Research Editor-in-Chief Jack E. James, PhD, National University of Ireland, Galway, Ireland, the roundtable "Caffeine and Physical Performance" presents a range of views on the extent to which caffeine may enhance athletic performance.
While the participants appear to agree that caffeine is likely to have performance-enhancing effects and seems to have the broadest effects of known stimulants for enhancing performance and endurance, they emphasize that the study data have been mixed.
Many factors can affect caffeine's impact on performance, including the type of exercise or sport and whether it is aerobic or anaerobic, caffeine dosing, the use of other stimulants (poly-supplementation), and the length of rest intervals.
Additional studies are needed to understand what factors can boost or inhibit the effects of caffeine and why some people may achieve enhanced performance with caffeine while others will not.