Comparison of a New Gas Exchange Measurement System During Exercise With a Reference System

Exercise gas exchange measurement is the gold-standard method for assessing maximal and submaximal aerobic performance. The measured variables are essential for the objective evaluation of exercise performance.

These parameters are used to assess an individual's performance level, determine training zones, and thereby personalize training programs. Their accuracy is therefore of critical importance.

However, the assessment of ventilatory parameters is complex, as it relies on measurements of airflow (using pneumotachographs) and gas concentrations in inspired and expired air (using O₂- and CO₂-sensitive sensors). The physical properties and composition of air differ between inspiration and expiration. In particular, the saturation of expired air with water vapor-which does not behave as an ideal gas-introduces significant challenges and can reduce the reliability of current measurement systems.

The accumulation of these individual sources of measurement error ultimately determines the overall quality and accuracy of a commercial gas exchange analysis system.

Nevertheless, athletes and coaches require regular access to these measurements in order to prescribe appropriate training intensities and evaluate training effectiveness. A recent comparative study of several commercially available portable systems highlighted substantial variability in both measurement accuracy and overall performance among existing devices. Consequently, the availability of a simple, accessible, and, above all, more accurate measurement system would represent a significant advance for the sports performance community.