The effects of caffeine ingestion on performance time, speed and power during a laboratory-based 1 km cycling time-trial

There is little published data in relation to the effects of caffeine upon cycling performance, speed and power in trained cyclists, especially during cycling of similar to 60s duration. To address this, eight trained cyclists performed a 1 km time-trial on an electronically braked cycle ergometer under three conditions: after ingestion of 5mg center dot kg(-1) caffeine, after ingestion of a placebo, or a control condition. The three time-trials were performed in a randomized order and performance time, mean speed, mean power and peak power were determined. Caffeine ingestion resulted in improved performance time (caffeine vs. placebo vs. control: 71.1 +/- 2.0 vs. 73.4 +/- 2.3 vs. 73.3 +/- 2.7 s; P = 0.02; mean +/- s). This change represented a 3.1% (95% confidence interval: 0.7-5.6) improvement compared with the placebo condition. Mean speed was also higher in the caffeine than placebo and control conditions (caffeine vs. placebo vs. control: 50.7 +/- 1.4 vs. 49.1 +/- 1.5 vs. 49.2 +/- 1.7 km center dot h(-1); P = 0.0005). Mean power increased after caffeine ingestion (caffeine vs. placebo vs. control: 523 +/- 43 vs. 505 +/- 46 vs. 504 +/- 38W; P = 0.007). Peak power also increased from 864 +/- 107W(placebo) and 830 +/- 87W(control) to 940 +/- 83W after caffeine ingestion (P = 0.027). These results provide support for previous research that found improved performance after caffeine ingestion during short-duration high-intensity exercise. The magnitude of the improvements observed in our study could be due to our use of sport-specific ergometry, a tablet form and trained participants.