Skip to main content
. 2015 Feb 16;593(Pt 8):1965–1979. doi: 10.1113/jphysiol.2014.285965

Table 3.

Cardiorespiratory variables during voluntary hyperpnoea at different percentages of maximal exercise ventilation

45% Inline graphic 60% Inline graphic 75% Inline graphic 100% Inline graphic
Parameter Men Women Men Women Men Women Men Women
Inline graphic (% max) 70 ± 3 72 ± 3 83 ± 1 83 ± 2 92 ± 1 92 ± 2 100 100
VT (l) 3.1 ± 0.2 1.7 ± 0.1* 3.3 ± 0.2 1.8 ± 0.1* 3.3 ± 0.2 1.9 ± 0.1* 3.1 ± 0.2 1.8 ± 0.1*
fR (breaths min−1) 27 ± 2 34 ± 2* 33 ± 2 39 ± 2 41 ± 3 46 ± 2 53 ± 2 60 ± 2*
ΔHR (beats min−1) 0 ± 3 −2 ± 3 7 ± 2 6 ± 4 7 ± 1 11 ± 3 20 ± 3 25 ± 3
tE/ttot 0.55 ± 0.01 0.55 ± 0.01 0.54 ± 0.01 0.55 ± 0.01 0.53 ± 0.01 0.55 ± 0.01 0.51 ± 0.01 0.53 ± 0.01
Inline graphic (mmHg) 40 ± 1 37 ± 1 40 ± 1 37 ± 1 35 ± 1 36 ± 1 31 ± 2 35 ± 2
Inline graphic (l min−1) 81 ± 7 55 ± 2* 106 ± 5 71 ± 3* 133 ± 7 88 ± 3* 165 ± 4 109 ± 4*
Inline graphic/ Inline graphic (ml O2 l−1) 1.4 ± 0.1 1.5 ± 0.1 1.7 ± 0.1 1.9 ± 0.1 1.7 ± 0.1 2.4 ± 0.2* 2.4 ± 0.2 3.5 ± 0.3*
Inline graphic/WOB (ml O2 J−1) 0.8 ± 0.1 1.1 ± 0.1* 0.8 ± 0.05 1.2 ± 0.1* 0.7 ± 0.04 1.1 ± 0.1* 0.7 ± 0.0 1.1 ± 0.1*
EfficiencyRM (%) 6.7 ± 0.5 5.1 ± 0.6* 6.4 ± 0.4 4.4 ± 0.3* 7.7 ± 0.94 4.8 ± 0.3* 7.2 ± 0.2 4.6 ± 0.4*
ΔPoe (cmH2O) 24 ± 1 19 ± 2 31 ± 2 24 ± 2 39 ± 3 32 ± 2 55 ± 4 47 ± 3*
WOB (J min−1) 142 ± 21 75 ± 8 232 ± 23 122 ± 12* 347 ± 38 199 ± 15* 593 ± 60 339 ± 27*
WOBres (% total) 40 ± 3 51 ± 5* 57 ± 3 54 ± 5 65 ± 3 65 ± 4 76 ± 2 76 ± 3
WOBel (% total) 60 ± 3 49 ± 6* 43 ± 3 46 ± 5 35 ± 3 35 ± 4 24 ± 2 24 ± 3
EELV (% FVC) 35 ± 2 44 ± 3* 33 ± 1 44 ± 3* 32 ± 1 43 ± 2* 38 ± 2 46 ± 3*
EILV (% FVC) 83 ± 2 83 ± 3 85 ± 2 86 ± 3 85 ± 2 88 ± 2 87 ± 1 88 ± 1
Inline graphic (%) 38 ± 3 33 ± 3 52 ± 3 40 ± 3* 67 ± 3 51 ± 3* 74 ± 4 67 ± 4

Abbreviations: EELV, end-expiratory lung volume; EfficiencyRM, efficiency of the respiratory muscles determined by dividing the measured Inline graphic by the calculated ideal oxygen uptake needed to perform the work; EILV, end-inspiratory lung volume; fR, breathing frequency; ΔHR, change in heart rate from rest to mimic; Inline graphic, end-tidal carbon dioxide tension; ΔPoe, oesophageal pressure swing; tE, expiratory time; ttot, total breath time; Inline graphic, minute ventilation; Inline graphic, ventilatory capacity; Inline graphic, maximal oxygen uptake; VT, tidal volume; Inline graphic, respiratory muscle oxygen uptake; WOB, work of breathing; WOBel, elastic work of breathing; and WOBres, resistive work of breathing. *Significantly different from men (P < 0.05).