Table 6.

Multiple linear regression with body mass index (BMI) and inspiratory fraction (inspiratory capacity and total lung capacity ratio) on the variables significant different across three oxygen pulse (O₂P) patterns (N = 45).

	BMI		IC/TLC
	coefficient	SE	coefficient	SE
Cardiothoracic ratio	0.011†	0.003	0.213*	0.101
EDRV, cm2	0.395*	0.16	2.479	6.54
Diffusing capacity for carbon monoxide % pred	0.028**	0.008	0.287	0.368
Maximum expiratory pressure pre¸cm H2O	2.962**	0.979	−19.8	42.5
O2Ppeak, mL/beat	0.228*	0.093	7.67¶	4.17
O2Ppeak, operable, mL/beat	0.207*	0.081	6.4¶	3.65
O2Ppeak% pred	−0.011	0.01	0.836¶	0.455
VT/TI/$\dot{\mathrm{V}}$O2 peak	−0.029*	0.012	0.378	0.563
Inspiratory duty cycle peak	−0.004*	0.002	0.125	0.083
Minute ventilation/$\dot{\mathrm{V}}$O2 peak	−1.093**	0.324	22.3	14.5
Minute ventilation/$\dot{\mathrm{V}}$ CO2 peak	−0.941**	0.275	−1.762	12.3

EDRV: sub-costal 4-chamber view end-diastolic right ventricle area, CO: carbon monoxide, pre: before exercise, post-pre: difference between after and before exercise, V_T/T_I/$\dot{\mathrm{V}}$O₂ peak: tidal volume and inspiratory time ratio normalized by oxygen uptake at peak exercise, $\dot{\mathrm{V}}$CO₂: CO₂ output. All variables were standardized. To avoid co-linearity problems, all variables were centered. SE is the standard error of the parameter estimates. ^* p < 0.05, ^**<0.01, ^†<0.0001, ^¶<0.1.