Caffeine ingestion attenuates the Vo2 slow component during intense exercise

Abstract

The purpose of this study was to analyze the effects of caffeine ingestion on the slow component of oxygen uptake (ΔVO2) during high-intensity endurance exercise. Nine subjects (8 male and 1 female; age: 21±1 years; VO2max: 57.9±l.5ml kg-1min-1) performed two 9-min tests on a treadmill at a running velocity eliciting 90% of their VO2max, 60 min after ingesting either a placebo capsule (PLAC) or a capsule containing a caffeine dose of 5 mg (kg body mass)-1 [CAFF]. The mean values of ΔVO2 were significantly lower in CAFF than in PLAC (83±31 ml min-1 vs. 167±26 ml min-1, respectively; p<0.05). These findings suggest that the ergogenic effect of caffeine in a high-intensity endurance exercise shown in previous research may be partly mediated by a possible attenuation of the VO2 slow component.