how do you guys deal with stomach pain/tension?

how do you guys deal with stomach pain/tension? Hey guys, The difference between when I talk fluent and stutter is that when I stutter my abdominal muscles become really tense and contract at the EXACT moment that I start speaking, sometimes this even hurts a little. I am 99% sure that I do block because of those muscles tensing up so my question is how do you guys deal with it or lower the amount of tension over there? I read about relaxing your rectum (lol) since when you relax a part of your respiration muscles all of them will relax as a result, does anyone has any experience with this? Cheers!