I have been slouching for at least the past decade. The slouching itself not terrible but my back is never completely straight. I've noticed that whenever I try to maintain a straight posture (shoulders back, back straight, chest out, etc.) I'd experience shortness of breath. It feels like there's something stuck in my throat and there's a light tightness in my chest. I'd feel somewhat suffocated and would have to return to my typical posture.
I have recessed mandible. To give an idea of the extent of recessiveness, I believe my surgical plan was to move mandible forward by around 10mm. I have a small airway, which is 1/3 of the average size, according to Gunson. However, this shortness of breath feeling remains even when I move my lower jaw forward to the point where my lower teeth are in front of my front teeth, which makes me question if it is caused by my recessed mandible. Does moving jaw forward mimic exactly the same effect as surgical forward movement?
I was never a mouth breather, and when I sleep I always naturally breathe through my nose. I don't have sleep apnea nor do I snore.
My question is do you think this difficulty with breathing when my back is straight is caused by my small airway? Or is it something that'll go away over time as I adjust to the new posture and change my breathing technique?