Table 3.

Cardiorespiratory and metabolic parameters during 80% $\dot{\text{V}}{\text{O}}_{\text{2}}$max exercise.

	PLA	PLA+C	BR	BR+C
HR (bpm)	180 ± 7	168 ± 49	178 ± 9	181 ± 7
$\dot{\text{V}}{\text{O}}_{\text{2}}$ (L/min)	4.0 ± 0.4	4.0 ± 0.4	3.8 ± 0.5	4.0 ± 0.4
$\dot{\text{V}}\text{C}{\text{O}}_{\text{2}}$ (L/min)	3.8 ± 0.3	3.8 ± 0.5	3.8 ± 0.5	3.8 ± 0.4
Carbohydrate oxidation (g/min)	4.37 ± 1.18	4.21 ± 1.31	4.60 ± 1.06	4.24 ± 1.36
Fat oxidation (g/min)	0.23 ± 0.54	0.29 ± 0.45	0.06 ± 0.33	0.27 ± 0.56
RER	0.97 ± 0.08	0.95 ± 0.07	0.99 ± 0.05	0.96 ± 0.08

Data are expressed as mean ± SD. HR: mean heart rate; $\dot{\text{V}}{\text{O}}_{\text{2}}$: mean oxygen uptake; $\dot{\text{V}}\text{C}{\text{O}}_{\text{2}}$: mean carbon dioxide production; RER: respiratory exchange ratio. PLA: placebo; PLA+C: placebo plus caffeine; BR: beetroot; BR+C: beetroot plus caffeine.