Effect of caffeinated drinks on substrate metabolism, caffeine excretion, and performance.

  title={Effect of caffeinated drinks on substrate metabolism, caffeine excretion, and performance.},
  author={Eva M. R. Kovacs and Stegen JHCH and Fred Brouns},
  journal={Journal of applied physiology},
  volume={85 2},
The effect of addition of different dosages of caffeine (Caf) to a carbohydrate-electrolyte solution (CES) on metabolism, Caf excretion, and performance was examined. Subjects (n = 15) ingested 8 ml/kg of water placebo (Pla-W), 7% CES (Pla-CES), or 7% CES with 150, 225, and 320 mg/l Caf (CES-150, CES-225, and CES-320, respectively) during a warm-up protocol (20 min) and 3 ml/kg at one-third and two-thirds of a 1-h time trial. Performance was improved with Caf supplementation: 62.5 +/- 1.3, 61.5… 

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