It feels weird to say but I hate them. I don't know if I Would describe them as painful, but they're definitely uncomfortable. It does not feel right in my chest or my throat. And I hate how irregular the rate at which I inhale/exhale air is when I try to do it slowly. And I can't breathe in/out for as long as I've been instructed to. Ok when I write all that out it kind of sounds like I have a medical problem. But to my knowledge my breathing is fine I passed the test with that thing doctors wear around their neck the stegosaur or whatevr
it depends on when in time you'd have asked me. When I first started having issues that demanded something like breathing exercises to manage - going from erratic breathing from overstimulation or panic attacks or anxiety attacks or whathave felt awful. My chest would feel wrong, my racing heart would be like HEY I WANNA SET THE TONE HERE and so there would be a physically uncomfortable clash
But i meditate and follow my breathing for mindfulness now, and i can say I have gotten used to how it feels to take control here. The discomfort will fade with use and practice, fyi - to me it ended up being like any other workout - initial discomfort followed by greater ease of action with repreated use.
if the act itself helps i have to recommend learning how to get used to it, and because of how brains work that's mostly repetition.