Do you have more info on this? I’ve suffered from GERD for a long time now and have found ways to mitigate the effects but this seems like an interesting potential treatment.
I can’t find the video I followed originally but what I do is pretty simple. I lie on the floor with one hand on my chest and one hand on my belly (just below the sternum). Then I breathe paying attention that only the lower hand moves, ie that I’m using my diaphragm. I put the weights (small metal plates) under the lower hand to add resistance. I recall seeing some papers explaining the mechanism being related to how the diaphragm kind of wraps around the oesophageal sphincter, so strengthening it helps it close.
Not the same thing, but I believe the parent commenter because I’ve seen multiple studies done where it was found that breathing exercises seemed to help with reflux: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3807765/