Don't mean to be stepping in where I shouldn't, but are you looking into how to make your gut feel better while running? Might want to try some elimination diets etc to see if it's a certain food/type of food. The frequent culprits are wheat and dairy, but could be something else.
Sorry for the unsolicited advice. I hate it when people do this to me, but couldn't keep my mouth shut...
No worries at all, I really appreciate the advice. I've paid attention to how different foods might affect it, but haven't actually completely eliminated one thing for an extended period of tome- I should do that. After years of this I think I just really need to see a doctor, which won't be happening before JWOC at this point.
FODMAP - I mentioned that at some point, right? . ;-) If you bump into the Culbergs, ask Kevin about it. I love traveling with them to various O meets just for the discussion about what is and is not considered edible. Can't say I've gone quite as hard-core into the elimination thing as Kevin has, but getting a better idea of what to pay attention to has helped.
Now, if I could only figure out why broccoli is sometimes almost poisonous (sprint camp pizza was so yummy and later so regrettable), and sometimes completely fine...
Reading what is included in FODMAP and tracking your diet and issues might help you realize what might be a possible culprit. The list is pretty broad, so my experience has been that elimination diets can be a challenge. If you eliminate something for a while and then reintroduce it with bad results, the positive experiment can give some clarity but there are too many possibilities. FODMAP includes many fruits, garlic/onions, dairy, wheat products, some vegetables and nuts, beans, and many types of sweeteners (sorbitol/mannitol/high fructose syrup). To Victoria's point, some problems depend on quantities and, maybe for the pizza, context. Hope you find your demon.