:2cents Sometimes I think the pain sets up a situation of hyperventilating which reduces CO2 and leads to anxiety and the process continues in a viscous cycle. If our body perceives there is a problem it is a normal adaptation to respond the physiological processes that will help us meet that challenge. I think where bag breathing, buteyko and diamox come in is help ensure there is an abundance of protective CO2 to prevent a domino effect in the direction of anaerobic glycolysis. I just like to view it as a tool to prevent any major derailment. Every cell should be able to respire optimally and efficiently when adequate-abundant CO2 is available. Its not like one buteyko session or diamox pill changes everything because we are constantly respiring I think we have to attend to our CO2 on a regular basis ( probably not if living at high altitudes). :2cents