Table 1.

Pulmonary ventilation and gas exchange at rest and during the 4th minute of cycle exercise

	Rest		50 W		75 W		100 W		Intensity	Nitrate	Interaction	80% Wpeak
	PLA	DNS	PLA	DNS	PLA	DNS	PLA	DNS	P	P	P	PLA	DNS
V̇e, L/min	14.8 ± 0.6	15.0 ± 0.5	35.5 ± 0.9	35.2 ± 1.2	35.5 ± 0.9	35.2 ± 1.2	44.4 ± 1.3	45.3 ± 1.4	< 0.001	0.801	0.473	146.1 ± 5.3	143.7 ± 5.2
ƒB, breaths/min	16.9 ± 1.9	16.7 ± 1.1	24.3 ± 1.1	25.1 ± 1.2	26.5 ± 1.3	27.3 ± 1.2	28.8 ± 1.5	28.9 ± 1.2	< 0.001	0.291	0.599	53.3 ± 1.9	54.4 ± 1.9
V̇t, L/min	1.04 ± 0.07	1.06 ± 0.08	1.51 ± 0.06	1.46 ± 0.05	1.74 ± 0.06	1.71 ± 0.06	1.97 ± 0.07	1.96 ± 0.07	< 0.001	0.332	0.592	2.76 ± 0.10	2.67 ± 0.12
V̇o2, L/min	0.37 ± 0.01	0.38 ± 0.01	1.18 ± 0.02	1.13 ± 0.03	1.45 ± 0.03	1.42 ± 0.03	1.70 ± 0.04	1.71 ± 0.03	< 0.001	0.19	0.226	3.15 ± 0.15	3.14 ± 0.16
V̇o2, % of max	12 ± 1	12 ± 1	37 ± 2	35 ± 2	45 ± 2	45 ± 2	53 ± 3	55 ± 3				97 ± 2	96 ± 2
V̇co2, L/min	0.27 ± 0.01	0.27 ± 0.01	0.91 ± 0.03	0.89 ± 0.03	1.19 ± 0.03	1.16 ± 0.03	1.48 ± 0.04	1.45 ± 0.04	< 0.001	0.153	0.706	3.05 ± 0.12	2.93 ± 0.13*
RER	0.74 ± 0.02	0.74 ± 0.03	0.77 ± 0.02	0.77 ± 0.01	0.83 ± 0.02	0.81 ± 0.01	0.86 ± 0.02	0.85 ± 0.02	< 0.001	0.335	0.787	0.98 ± 0.02	0.94 ± 0.02
V̇e/ V̇o2, L/min	41.4 ± 3.4	40.3 ± 3.3	27.6 ± 0.8	28.5 ± 0.7	27.9 ± 0.6	29.2 ± 0.9	29.5 ± 1.0	29.9 ± 0.9	0.013	0.12	0.604	43.7 ± 1.7	43.2 ± 1.6
V̇e/ V̇co2, L/min	51.4 ± 3.7	51.2 ± 3.4	35.8 ± 1.2	37.4 ± 1.1	33.9 ± 0.6	35.9 ± 0.9	34.4 ± 0.8	35.3 ± 0.9	0.027	0.042	0.474	45.0 ± 1.3	45.9 ± 1.7

DNS, dietary nitrate supplementation; ƒ_B, breathing frequency; PLA, placebo; V̇_E, minute ventilation; V̇_t, tidal volume; V̇co₂, carbon dioxide production; V̇o_2, oxygen consumption. *P < 0.05 vs. PLA. n = 11.