Table 2.
Effect of caffeine or placebo on heart rate (HR), rating of perceived exertion (RPE), oxygen uptake (VO2) and respiratory exchange ratio (RER) during 15 min of steady state cycling (Phase A). Values are means (±SD, n=10).
| Time | Placebo | Caffeine | Mean change (%) ± 90% confidence limits |
P | |
|---|---|---|---|---|---|
| HR | 5 min | 130 (12) | 129 (10) | -.07 (.57) | |
| 10 min | 134 (10) | 136 (13) | -.37 (.68) | ||
| 15 min | 138 (12) | 140 (12 | .23 (.61) | .81 | |
| RPE | 5 min | 11 (2) | 10 (2) | -.04 (.56) | |
| 10 min | 11 (2) | 11 (2) | - | ||
| 15 min | 11 (2) | 11 (2) | - | .74 | |
| VO2 (mL·kg-1·min-1) | 5 min | 16.05 (3.92) | 16.93 (4.03) | .22 (.24) | |
| 10 min | 16.79 (3.91) | 17.27 (3.33) | .12 (.19) | ||
| 15 min | 15.85 (3.64) | 17.78 (3.93) | .53 (.28) | .08 | |
| RER | 5 min | .95 (.08) | .94 (.08) | -.21 (.52) | |
| 10 min | .89 (.05) | .91 (.07) | .43 (1.18) | ||
| 15 min | .90 (.04) | .88 (.08) | -.35 (.73) | .31 |
P indicates interaction effect of time and trial.