There you are only a short time away from your competition, you’ve nailed it and you’re ready to show the world your great physique. Next thing you know you’re vomiting, diarrhea, cramps, etc. and you feel your success on stage is slipping away from you. No it’s not a cold–its food poisoning (correctly termed foodborne illness)! I have heard this story all too often, so to be safe seek medical attention immediately when stricken with food poisoning.
Here is an informative chart (in PDF format) on the bugs, common food sources, how soon you get sick. The chart also shows how long complications ma last, common symptoms, other symptoms, and possible complications.