Table 2.

Vascular and metabolic response to knee‐extensor exercise at 50% of maximum work rate (WR_max) in healthy controls and in patients with heart failure with reduced ejection fraction (HFrEF) before (pre) and after (post) 8 weeks of knee‐extensor exercise training

	Controls	HFrEF pre	HFrEF post
50% WRmax (W)	20 ± 3	15 ± 2#	21 ± 3
HR (beats/min)	94 ± 3	92 ± 6	90 ± 3
${\dot{V}}_{{\mathrm{O}}_2}$ leg (ml/min)	313 ± 28	275 ± 23.5#	324 ± 17*
Q leg (ml/min)	2450 ± 223	2048 ± 159#	2529 ± 238*
${\dot{Q}}_{{\mathrm{O}}_2}$ leg (ml/min)	460 ± 41	401 ± 28#	476 ± 48*
Hb (g/dl)	13.9 ± 0.3	12.7 ± 0.6	13.1 ± 0.5
$S_{\mathrm{a}{\mathrm{O}}_2}$ (%)	96 ± 1	97.1 ± 0.6	97.7 ± 0.4
$C_{\mathrm{a}{\mathrm{O}}_2}$ (ml/100 ml)	18.8 ± 0.3	17.3 ± 0.9	18.1 ± 0.8
$C_{\mathrm{v}{\mathrm{O}}_2}$ (ml/100 ml)	5.9 ± 0.5	4.4 ± 0.6	5.2 ± 0.9
$P_{\mathrm{a}{\mathrm{O}}_2}$ (mmHg)	99.9 ± 3	95.3 ± 6.2	93.6 ± 3.5
$P_{\mathrm{v}{\mathrm{O}}_2}$ (mmHg)	23.0 ± 1.1	19.6 ± 0.9	20.3 ± 1.2
LVR (mmHg/l/min)	41 ± 6	47 ± 7#	39 ± 6*#
MAP (mmHg)	121 ± 11	110 ± 6	112 ± 7
MAP − MVP (mmHg)	100 ± 12	95 ± 7	95 ± 6
Noradrenaline spillover (nm/min)	0.68 ± 0.2	3.30 ± 0.3#	1.43 ± 0.5*#

WR_max, maximum work rate; ${\dot{V}}_{{\mathrm{O}}_2}$ leg, leg oxygen uptake; HR, heart rate; Q leg, leg blood flow; ${\dot{Q}}_{{\mathrm{O}}_2}$ leg, leg oxygen delivery; $S_{\mathrm{a}{\mathrm{O}}_2}$, arterial O₂ saturation; $C_{\mathrm{a}{\mathrm{O}}_2}$, arterial O₂ concentration; $C_{\mathrm{v}{\mathrm{O}}_2}$, venous O₂ concentration; $P_{\mathrm{a}{\mathrm{O}}_2}$, arterial O₂ partial pressure; $P_{\mathrm{v}{\mathrm{O}}_2}$, venous O₂ partial pressure; LVR, leg vascular resistance; MAP, mean arterial pressure; MVP, mean venous pressure. Data are expressed as mean ± SE; ^* P < 0.05 (post vs. pre); ^# P < 0.05 (HFrEF vs. controls).