Hi, I Am A 34 Year Old Female, I Work

Hi, I am a 34 year old female, i work out 5 days a week. After each workout (pretty intense) I have strong stomach pain and need to rush to the washroom and i am in there a good 30mn in pain and pooing sometimes diarrahea. Last year I had this and i found out that by eating gluten free before my workout it made the difference but now i am back to square 1.