Arterial pH, bicarbonate, base excess, PaCO2, minute ventilation, ratio of arterial oxygen partial pressure to fraction of inspired oxygen and PEEP did not differ between the low- and high-MAP groups (Table S2 in Additional file 2).
This is true if a low Vt/high respiratory rate strategy is compared with a higher Vt/lower respiratory rate at comparable minute ventilation (physiology tells us that the dead space : minute ventilation ratio will rise, decreasing the efficiency of the system).
An increase in CO2 values was seen despite the same minute ventilation and VD/VT ratio, probably due to a high VCO2.
There was a disproportionate decrease in oxygen consumption relative to body weight support which led to an attenuation of heart rate and rating of perceived exertion and, to a lesser degree, respiratory exchange ratio, minute ventilation, and respiratory frequency between each level of body weight support and running speed.
There was a large attenuation of oxygen consumption (VO2) relative to BWS (p < 0.001), while there were trivial-moderate reductions in respiratory exchange ratio, minute ventilation, and respiratory frequency (p > 0.05), and small-large effects on HR and RPE (p < 0.01).
Minute ventilation and respiratory exchange ratio (RER) were recorded continuously during each inclination using an Oxycon Pro (Jaeger BeNeLux, Breda, Netherlands).
Oxygen uptake, output of carbon dioxide, the respiratory exchange ratio, minute ventilation, and breathing frequency were assessed by a mixed expired procedure involving an Oxycon Pro apparatus (Jaeger GmbH, Hoechberg, Germany) equipped with an inspiratory flowmeter.
During the constant flow ventilation the ventilator was set at a minute ventilation of 5 25l/min, an inspiratory:expiratory ratio of 1 2, and a rate of 12, 15 or 20 breaths/min.
The ratio of minute ventilation during cycling compared to in bus or car was higher in women than in men.
In addition, we calculated the ratio in minute ventilation between commuting by bicycle, bus and car for all participants (table 4).
The mean ratio of minute ventilation of cyclists compared to car passengers differs just slightly when using the equation of Samet for men.
