Skip to main content

Table 2 Respiratory and metabolic values during submaximal and maximal exercise

From: Low doses of caffeine reduce heart rate during submaximal cycle ergometry

% of VO2max 30 45 63 Peak VO2
VE (L·min-1)     
   PLA 28.0 ± 2.3 41.5 ± 2.4 56.6 ± 3.4 129.0 ± 15.8
   1.5 28.6 ± 3.0 42.7 ± 3.8 59.3 ± 5.3 129.1 ± 13.4
   3.0 28.5 ± 2.4 42.0 ± 3.2 59.5 ± 6.0 127.1 ± 12.3
Bf (breaths·min-1)     
   PLA 19.3 ± 2.8 21.3 ± 2.8 23.5 ± 4.1 41.0 ± 8.3
   1.5 18.7 ± 3.1 20.8 ± 3.2 23.2 ± 4.4 38.8 ± 6.0
   3.0 18.0 ± 2.6 20.0 ± 3.3* 23.3 ± 4.1 38.9 ± 6.7
VT (L·breath-1)     
   PLA 1.55 ± 0.23 2.02 ± 0.27 2.50 ± 0.41 3.21 ± 0.36
   1.5 1.63 ± 0.27 2.13 ± 0.28 2.64 ± 0.36 3.38 ± 0.31
   3.0 1.67 ± 0.19 2.22 ± 0.42 2.63 ± 0.41 3.32 ± 0.36
VO2(ml·kg-1·min-1)     
   PLA 14.9 ± 1.6 22.6 ± 2.4 31.0 ± 3.3 49.7 ± 4.4
   1.5 14.8 ± 0.9 22.7 ± 1.7 31.4 ± 2.7 50.7 ± 5.6
   3.0 15.2 ± 1.0 23.0 ± 2.1 31.9 ± 3.2 50.3 ± 4.1
RER     
   PLA 0.85 ± 0.04 0.90 ± 0.02 0.94 ± 0.03 1.21 ± 0.05
   1.5 0.86 ± 0.05 0.92 ± 0.03 0.96 ± 0.04 1.18 ± 0.06
   3.0 0.82 ± 0.06 0.88 ± 0.05*† 0.93 ± 0.03 1.16 ± 0.06*†
RPE     
   PLA 8.4 ± 1.3 11.7 ± 1.5 13.8 ± 0.9 19.0 ± 0.6
   1.5 8.2 ± 1.3 11.0 ± 0.7 13.4 ± 1.0 19.1 ± 0.6
   3.0 7.9 ± 1.1 11.3 ± 1.2 13.4 ± 1.0 19.3 ± 0.6
  1. Values listed as mean ± SD. VE, ventilation; Bf, breathing frequency; VT, tidal volume; VO2, oxygen consumption; RER, respiratory exchange ratio; RPE, rating of perceived exertion. PLA, placebo; 1.5 and 3.0 represent dose of caffeine in mg·kg body weight-1.
  2. * Significantly different from placebo (p < 0.05).
  3. Significantly different from 1.5 caffeine in mg·kg body weight-1. (p < 0.05).