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The impact of prior coffee consumption on the subsequent ergogenic effect of anhydrous caffeine
1Defence Research and Development Canada, Toronto, Canada.
Abstract:
This study examined whether the prior consumption of coffee (COF) decreased the ergogenic effect of the subsequent ingestion of anhydrous caffeine (CAF). Thirteen subjects performed 6 rides to exhaustion at 80 % VO2max 1.5 h after ingesting combinations of COF, decaffeinated coffee (DECOF), CAF, or placebo. The conditions were DECOF + placebo (A), DECOF + CAF (5 mg/kg) (B), COF (1.1 mg/kg caffeine) + CAF (5 mg/kg) (C), COF + CAF (3 mg/kg) (D), COF + CAF (7 mg/kg) (E), and colored water + CAF (5 mg/kg) (F). Times to exhaustion were significantly greater for all trials with CAF versus placebo (trial A). Exercise times (in minutes) were: 21.7 +/- 8.1, 29.0 +/- 7.4, 27.8 +/- 10.8, 25.1 +/-7.9, 26.4 +/- 8.0 and 26.8 +/- 8.1 for trials A through F, respectively. In conclusion, the prior consumption of COF did not decrease the ergogenic effect of the subsequent ingestion of anhydrous CAF.
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