The Metabolic and Performance Effects of Caffeine Compared to Coffee during Endurance Exercise. e59561

• Published in: PloS one 2013-04, Vol.8 (4)
• Main Authors: Hodgson, Adrian B, Randell, Rebecca K, Jeukendrup, Asker E
• Format: Article
• Language: English
• ISSN: 1932-6203
• DOI: 10.1371/journal.pone.0059561

There is consistent evidence supporting the ergogenic effects of caffeine for endurance based exercise. However, whether caffeine ingested through coffee has the same effects is still subject to debate. The primary aim of the study was to investigate the performance enhancing effects of caffeine and coffee using a time trial performance test, while also investigating the metabolic effects of caffeine and coffee. In a single-blind, crossover, randomised counter-balanced study design, eight trained male cyclists/triathletes (Mean plus or minus SD: Age 41 plus or minus 7y, Height 1.80 plus or minus 0.04 m, Weight 78.9 plus or minus 4.1 kg, VO2 max 58 plus or minus 3 ml times kg-1 times min-1) completed 30 min of steady-state (SS) cycling at approximately 55% VO2max followed by a 45 min energy based target time trial (TT). One hour prior to exercise each athlete consumed drinks consisting of caffeine (5 mg CAF/kg BW), instant coffee (5 mg CAF/kg BW), instant decaffeinated coffee or placebo. The set workloads produced similar relative exercise intensities during the SS for all drinks, with no observed difference in carbohydrate or fat oxidation. Performance times during the TT were significantly faster (~5.0%) for both caffeine and coffee when compared to placebo and decaf (38.35 plus or minus 1.53, 38.27 plus or minus 1.80, 40.23 plus or minus 1.98, 40.31 plus or minus 1.22 min respectively, p