Dispelling the myth that habitual caffeine consumption influences the performance response to acute caffeine supplementation

Objective: To investigate the influence of habitual caffeine intake on aerobic exercise performance responses to acute caffeine supplementation. Methods: A double-blind, crossover, counterbalanced study was performed. Forty male endurance-trained cyclists were allocated into tertiles according to their daily caffeine intake: low (58 ± 29 mg.d-1), moderate (143 ± 25 mg.d-1), and high consumers (351 ± 139 mg.d-1). Participants completed three trials in which they performed simulated cycling time-trials in the fastest time possible following ingestion of: caffeine (CAF: 6 mg.kg-1 BM), placebo (PLA), and no supplement (CON). Results: Mixed-model analysis revealed time-trial performance was significantly improved in CAF compared to PLA and CON (29.92±2.18 min vs 30.81±2.67 and 31.14±2.71 min; P = 0.05). Blood lactate and ratings of perceived exertion were not different between trials and tertiles (P>0.05). Conclusion: Performance effects of acute caffeine supplementation during a ~30 min cycling TT performance were not influenced by the level of habitual caffeine consumption