Table 2.

Cardiorespiratory and metabolic parameters during 60% $\dot{\text{V}}{\text{O}}_{\text{2}}$max exercise.

	PLA	PLA+C	BR	BR+C
HR (bpm)	152 ± 11	155 ± 10	151 ± 12	152 ± 13
${\dot{\text{V}}\text{O}}_{\text{2}}$ (L/min)	2.8 ± 0.4	2.8 ± 0.3	2.8 ± 0.4	2.9 ± 0.4
${\dot{\text{V}}\text{CO}}_{\text{2}}$ (L/min)	2.5 ± 0.3	2.6 ± 0.4	2.6 ± 0.4	2.6 ± 0.3
RPE	13.6 ± 1.9	13.1 ± 2.1	133 ± 1.7	12.9 ± 1.9
Carbohydrate oxidation (g/min)	2.25 ± 0.69	2.33 ± 0.83	2.56 ± 0.61	2.35 ± 0.81
Fat oxidation (g/min)	0.48 ± 0.33	0.46 ± 0.31	0.35 ± 0.20	0.48 ± 0.35
RER	0.90 ± 0.06	0.90 ± 0.06	0.93 ± 0.04	0.90 ± 0.06

Data are expressed as mean ± SD. HR: mean heart rate; ${\dot{\text{V}}\text{O}}_{\text{2}}$: mean oxygen uptake; ${\dot{\text{V}}\text{CO}}_{\text{2}}$: mean carbon dioxide production; RPE: mean ratings of perceived exertion; RER: respiratory exchange ratio.

PLA: placebo; PLA+C: placebo plus caffeine; BR: beetroot; BR+C: beetroot plus caffeine.