Table 3.

Respiratory and hemodynamic responses to loading and unloading during moderate exercise

	Healthy					HFREF
	S	L1	L2	UL1	UL2	S	L1	L2	UL1	UL2
Peak inspiratory ITP (cmH₂O)	−10.2 ± 4.6 ^* ^†	−12.0 ± 4.5	−13.9 ± 6.1	−7.0 ± 5.2	−3.2 ± 5.4	−7.8 ± 3.4 ^* ^†	−10.0 ± 2.9	−11.3 ± 3.4	−5.1 ± 3.5	−2.0 ± 2.7
Peak expiratory ITP (cmH₂O)	3.8 ± 5.0 ^*	3.5 ± 5.8	4.4 ± 6.6	4.8 ± 4.4	5.2 ± 4.0	4.4 ± 1.9 ^*	5.1 ± 1.9	5.4 ± 1.7	6.4 ± 2.2	5.4 ± 1.6
Pdi (cmH₂O)	10.3 ± 4.5 ^* ^†	11.9 ± 4.3	13.8 ± 5.9	6.9 ± 5.1	2.8 ± 5.2	9.1 ± 8.2 ^* ^†	11.4 ± 8.0	12.8 ± 8.7	6.5 ± 7.7	3.5 ± 6.6
Tidal volume (L)	3.07 ± 0.90 ^* ^†	3.33 ± 1.05	3.47 ± 1.17	3.81 ± 1.13	4.03 ± 0.97	2.64 ± 0.52 ^* ^†	2.91 ± 0.77	2.96 ± 0.76	3.49 ± 0.81	3.43 ± 0.80
RR (breath/min)	24.9 ± 6.1 ^* ^†	23.0 ± 7.1	22.5 ± 6.8	25.8 ± 5.9	26.8 ± 3.6	25.7 ± 5.8 ^* ^†	22.1 ± 4.3	21.1 ± 5.1	26.1 ± 7.2	29.1 ± 5.9
MAP (mmHg)	115 ± 12 ^‡	116 ± 13	114 ± 14	109 ± 14	106 ± 15	93 ± 13 ^‡	97 ± 16	94 ± 12	98 ± 20	97 ± 18
SVR (dyn·s/cm⁵)	829 ± 144 ^‡	795 ± 177	791 ± 180	729 ± 186	715 ± 189	728 ± 344 ^‡	735 ± 341	712 ± 307	827 ± 436	804 ± 407

main effect for unloading,

^†

main effect for loading,

^‡

group and condition interaction for unloading, HFREF: Heart failure and reduced ejection fraction, ITP: intrathoracic pressure, Pdi: transdiaphragmatic pressure, RR: respiratory rate, MAP: mean arterial pressure, SVR: systemic vascular resistance