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

Author(s)

Goncalves, Livia de Souza ; Painelli, Vitor de Salles ; Yamaguchi, Guilherme ; de Oliveira, Luana Farias ; Saunders, Bryan ; da Silva, Rafael Pires ; Maciel, Erika ; Artioli, Guilherme Giannini ; Roschel, Hamilton ; Gualano, Bruno

• Document type: Journal article
• Source: Journal of Applied Physiology; v. 123, n. 1, p. 213-220, JUL 2017.
• Web of Science Citations: 44

Abstract

This study investigates the influence of habitual caffeine intake on aerobic exercise-performance responses to acute caffeine supplementation. A double-blind, crossover, counterbalanced study was performed. Forty male endurancetrained cyclists were allocated into tertiles, according to their daily caffeine intake: low (58 +/- 29 mg/d), moderate (143 +/- 25 mg/d), and high (351 +/- 139 mg/d) consumers. Participants completed three trials in which they performed simulated cycling time trials (TTs) in the fastest time possible following ingestion of the following: caffeine (CAF: 6 mg/kg body mass), placebo (PLA), and no supplement (CON). A mixed-model analysis revealed that TT performance was significantly improved in CAF compared with PLA and CON (29.92 +/- 2.18 vs. 30.81 +/- 2.67 and 31.14 +/- 2.71 min, respectively; P = 0.0002). Analysis of covariance revealed no influence of habitual caffeine intake as a covariate on exercise performance (P = 0.47). TT performance was not significantly different among tertiles (P = 0.75). No correlation was observed between habitual caffeine intake and absolute changes (CAF = CON) in TT performance with caffeine (P = 0.524). Individual analysis showed that eight, seven, and five individuals improved above the variation of the test in CAF in the low, moderate, and high tertiles, respectively. A Fisher's exact test did not show any significant differences in the number of individuals who improved in CAF among the tertiles (P > 0.05). Blood lactate and ratings of perceived exertion were not different between trials and tertiles (P > 0.05). Performance effects of acute caffeine supplementation during an similar to 30-min cycling TT performance were not influenced by the level of habitual caffeine consumption. (AU)

• FAPESP's process: 11/19513-2 - Effects of Chronic Beta-Alanine Supplementation with and without Acute Sodium Bicarbonate Ingestion on Peak Muscle Carnosine Concentration, Washout and High-Intensity Exercise Performance
• Grantee: Bryan Saunders
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 13/14746-4 - Carnosine metabolism in skeletal muscle: a multi-approach study
• Grantee: Bruno Gualano
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 12/13026-5 - SUPPLEMENTATION OF B’ETA-ALANINE AND SODIUM BICARBONATE: EFFECTS ON ENERGETIC SYSTEM CONTRIBUTION DURING INTERMITTENT ANAEROBIC EXERCISE
• Grantee: Rafael Pires da Silva
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 13/04806-0 - Effects of 12 weeks of high-intensity intermittent training on intramuscular carnosine concentrations
• Grantee: Vitor de Salles Painelli
• Support Opportunities: Scholarships in Brazil - Doctorate