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The effects of caffeine ingestion on time trial cycling performance
L R McNaughton1, R J Lovell, J Siegler
1Applied Physiology Laboratory, University of Hull, UK.
Purpose:
The purpose of this work was to determine the effects of caffeine on high intensity time trial (TT) cycling performance in well-trained subjects.
Subjects:
Six male cyclists with the following physical characteristics (mean +/- SD) age 30.7 +/- 12, height 179.3 +/- 7.5 cm, mass 70.0 +/- 7.5 kg, VO2max 65.0 +/- 6.3 mL.kg-1.min-1 undertook three 1-h TT performances, control (C), placebo (P) and caffeine (CAF), on a Velotron cycle ergometer conducted in a double-blind, random fashion. Subjects rested for 60 min and were then given CAF or P in a dose of 6 mg.kg-1 body mass and then commenced exercise after another 60 min of rest. Before ingestion, 60 min postingestion, and at the end of the TT, finger-prick blood samples were analyzed for lactate.
Results:
The cyclists rode significantly further in the CAF trial (28.0 +/- 1.3 km) than they did in the C (26.3 +/- 1.5 km, P < .01) or P (26.4 +/- 1.5 km, P < .02) trials. No differences were seen in heart rate data throughout the TT (P > .05). Blood lactate levels were significantly higher at the end of the trials than either at rest or postingestion (P < .0001), but there were no differences between the three trial groups.
Conclusion:
On the basis of the data, we concluded that performance was improved with the use of a caffeine supplement.
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