Hmm, I've had that issue in the past which led to a really unfortunate situation in a neighborhood once. Sometimes the question is not if you are going to make it, but how big of a skid mark are you going to leave.
As for your issue, it really dpends on the person, though there are certain things that are more prevelent. For example, if you're sports drink is introducing carbohydrates into your body at a percentage higher than what you can process, it gets sent on the express lane out. I think that figure is about 8% concentration, by weight.