Validation of Aerosport KB1-C portable metabolic system

The purpose of this study was to test the validity of the Aerosport KB1-C portable metabolic measurement system against the criterion Douglas bag method. During cycle ergometry, simultaneous measurements of minute ventilation (V̇(E)), oxygen consumption (V̇CO₂), and carbon dioxide production (V̇CO₂) were made at rest and at power outputs of 50, 100, 150, 200, and 250 W. No significant differences (P > 0.05) were observed for V̇(E), V̇O₂, and V̇CO₂, between the KB1-C and Douglas bag at 100, 150, and 250 W, while the KB1-C was significantly different (P < 0.05) from Douglas bag values at rest, 50, and 200W. R values were found to be significantly different (P < 0.05) at 100, 150, and 200 W, while no significant differences were observed at rest, 50, and 250 W. The fractional concentrations of oxygen (F(E)O₂) and carbon dioxide (F(E)C0₂) were not significantly different at 50, 100, 200, and 250 W while values at rest and 150W were significantly different (P < 0.05). These findings show that the Aerosport KB1-C portable metabolic system is acceptable for measuring oxygen uptake in the range of 1.5 and 3.5 L.min^-1, using the medium flow pneumotach setting. At lower intensities, the low-flow pneumotach setting provides acceptable results.