There is a feedback loop that characterizes the stress/anxiety response, where people breathe faster, which in turn increases the stress response, causing even faster breathing. People with chronic anxiety also develop decreased CO2 tolerance over time[1] from this rapid breathing, perpetuating the chronic rapid breath.
Breath exercises that increase CO2 tolerance like Buteyko breathing allow one to interrupt this process. It's not clear to me exactly what the increased CO2 is doing, if anything, but it's clear that this works to escape this chronic stress state, which is really unhealthy.
Breath exercises that increase CO2 tolerance like Buteyko breathing allow one to interrupt this process. It's not clear to me exactly what the increased CO2 is doing, if anything, but it's clear that this works to escape this chronic stress state, which is really unhealthy.
I think the Radiolab breath episode discusses this well: https://radiolab.org/episodes/breath
[1] https://pubmed.ncbi.nlm.nih.gov/11015814/