In freediving, being able to hold your breath for extended periods of time is a skill that allows for longer dives and more comfortable dives. A major role in this is played by the CO2 tolerance one has.

One way of training for better CO2 tolerance is CO2 tables. They come in various forms but the main trait is that it gradually exposes your body to breath holds with higher and higher initial CO2 levels.

The tool you can download (excel+vba based, free, no commercials) creates a table for you of 8 consecutive holds having as starting point your current personal best. The variables are in the cells highlighted in yellow (PB, % of PB for the length of the hold, length of the first recovery).

You will get acoustic cues for when to start a hold, when to start recovery, and count down at 20 seconds, 10 seconds, and 5 seconds before a hold. This kind of table is safe to practice by oneself, laying on the floor or on a couch.

Reach out for suggested improvements 🙂