Abstract des Autors

The aim of the study was to compare two ergospirometry systems, OxyconGamma ((OG), Mijnhardt) and the portable device X1 (Cortex) with measurements by the Douglas-bag-method (DBM). 16 recreational athletes exercised once (4) or twice (12) on a cycle ergometer (4x5 minutes starting with 50 or 100 W, increment 50 W). From minute 3 to 4 of each step or 1 minute before cessation of exercise simultaneous measurements of DBM and OG or X1 were performed. With DBM the measurements of the ventilation (Ve) were significantly higher than with OG (up to 11% in the average) and X1 (up to 16%). Compared to DBM calculations of VO2 were significantly lower at 150 to 250 W by OG (up to 8% in the average) and 9% higher at 100 Watt but 3% lower at 250 W by X1. At 100 W VCO2 was calculated significantly higher by OG and X1 (in the average 5% and 12% respectively) and at 150 W with X1 (6%) compared to DBM. Significantly lower FeO2 and higher FeCO2 measurements with OG and X1 than with DBM account for smaller differences in VO2 and VCO2 than could be expected because of the discrepancies in Ve. However, there was a significant correlation of Ve with delta-VO2 and delta-VCO2 (X1 only). We suspect that high respiratory rates, high ventilation and humidity of the expired air may interfere with measurements and calculations by OG and X1. Verf.-Referat