Table 7.

Caffeine concentration predrug and before, during, and at the end of exercise at 80% V˙o 2max 1, 3, and 6 h after caffeine or placebo ingestion

1 h3 h6 h
CaffeinePlaceboCaffeinePlaceboCaffeinePlacebo
Nonusers7-150 (n = 8)
 Predrug0.4 ± 0.40.4 ± 0.40.5 ± 0.40.7 ± 0.70.6 ± 0.60.6 ± 0.6
 Before exercise26.2 ± 12.97-151 0.4 ± 0.430.5 ± 5.30.3 ± 0.523.4 ± 7.17-152 0.5 ± 0.3
 During exercise30.1 ± 12.50.4 ± 0.330.1 ± 5.20.3 ± 0.523.2 ± 8.07-152 0.3 ± 0.3
 Postexercise32.3 ± 12.00.5 ± 0.930.7 ± 5.20.3 ± 0.422.1 ± 6.87-152 0.4 ± 0.3
Users (n = 11)
 Predrug3.8 ± 2.83.4 ± 2.73.3 ± 4.23.2 ± 2.54.0 ± 2.74.1 ± 2.8
 Before exercise32.9 ± 10.17-151 2.7 ± 2.333.1 ± 8.62.5 ± 1.926.9 ± 7.57-152 2.4 ± 1.6
 During exercise35.7 ± 8.42.5 ± 2.233.8 ± 6.42.3 ± 1.827.1 ± 5.37-152 2.1 ± 1.5
 Postexercise36.3 ± 7.42.5 ± 2.133.7 ± 6.42.4 ± 1.626.8 ± 7.87-152 2.0 ± 1.4
  • Values are means ± SD (in μmol/l).

  • F7-150 Nonusers < users.

  • F7-151 Caffeine 1 h before exercise < caffeine 1 h postexercise.

  • F7-152 Caffeine 6 h < caffeine 1 and 3 h.