Does regular caffeine use reduce the benefit of caffeine on exercise performance?

Some studies show that sustained daily use of caffeine can blunt some of the physiological responses following caffeine intake,^{[1][2][3][4][5][6]} and may reduce its exercise performance-enhancing effects.^[7][8][9] Therefore, habitual caffeine users may experience a lower performance-enhancing effect than nonhabitual users. However, not all studies find this “tolerance effect”,^[10][11] and a recent meta-analysis concludes that caffeine improves exercise performance even in habitual caffeine users.^[12]

It has been suggested that athletes who regularly use caffeine and are seeking performance benefits could take a slightly higher dose before exercise.^[13] Another solution would be for athletes to abstain from caffeine intake in the days before a competition to remove tolerance and thereby exploit the performance-enhancing effects of pre-exercise caffeine intake. However, this approach is not recommended because withdrawing from caffeine can increase a person's susceptibility to the unwanted side effects of caffeine.^[13] Given the between-person variability in the response to caffeine (both benefits and side effects), the preferred solution is for athletes to experiment with caffeine doses and timing before competition day.^[13]