Wagner diagram for modeling O₂pathway-calculation and graphical display by the Helsinki O₂Pathway Tool

Area of Science:

• Physiology
• Exercise Science
• Computational Biology

Background:

• Maximal O2 uptake (V˙O2max) is crucial for physical capacity and health, reflecting integrated O2 transport and utilization.
• Understanding individual O2 pathway components offers mechanistic insights into exercise intolerance and adaptations.
• The Wagner diagram provides a framework for analyzing the O2 pathway.

Purpose of the Study:

• To develop a desktop application, the Helsinki O2 Pathway Tool (HO2PT), for modeling the O2 pathway.
• To provide numerical and graphical displays of the O2 pathway based on the Wagner diagram.
• To enhance accessibility and usability of the integrated physiological model.

Main Methods:

• Developed HO2PT using Python, integrating the Fick principle and Fick's law of diffusion.
• The tool imports, calculates, and displays variables of the Wagner diagram.
• Utilized open-source Python libraries for broad compatibility.

Main Results:

• HO2PT models the O2 pathway numerically and graphically via the Wagner diagram.
• The tool visualizes conditions where oxygen transport limits mitochondrial oxidative capacity.
• HO2PT is freely available online for Windows, macOS, and Linux.

Conclusions:

• HO2PT offers a novel platform for examining V˙O2max and its determinants.
• The tool improves access to and application of the integrated physiological model.
• HO2PT benefits scientific research, education, exercise testing, sports coaching, and clinical medicine.