CAFFEINE INCREASES MAXIMAL ANAEROBIC POWER AND BLOOD LACTATE CONCENTRATION

The aim of this study was to specify the effects of caffeine on maximal anaerobic power (W(max)). A group of 14 subjects ingested caffeine (250 mg) or placebo in random double-blind order. The W(max) was determined using a force-velocity exercise test. In addition, we measured blood lactate concentration for each load at the end of pedalling and after 5 min of recovery. We observed that caffeine increased W(max) [964 (SEM 65.77) W with caffeine vs 903.7 (SEM 52.62) W with placebo; P < 0.02] and blood lactate concentration both at the end of pedalling [8.36 (SEM 0.95) mmol.l-1 with caffeine vs 7.17 (SEM 0.53) mmol.l-1 with placebo; P < 0.01] and after 5 min of recovery [10.23 (SEM 0.97) mmol.l-1 with caffeine vs 8.35 (SEM 0.66) mmol.l-1 with placebo; P < 0.04]. The quotient lactate concentration power (mmol.l-1.W-1) also increased with caffeine at the end of pedalling [7.6.10(-3) (SEM 3.82.10(-5)) vs 6.85.10(-3) (SEM 3.01.10(-5)); P < 0.01] and after 5 min of recovery [9.82 . 10(-3) (SEM 4.28 . 10(-5)) vs 8.84 . 10(-3) (SEM 3.58 . 10(-5)); P < 0.02]. We concluded that caffeine increased both W(max) and blood lactate concentration.