RUNNER'S TROTS
Proper gastro-intestinal functioning requires a relatively still body and ample blood supply. When you run, you are obviously not standing still and the blood is diverted to your heart and working muscles, not to your GI tract. Low blood sugar and dehydration further aggravate the situation. And no matter how much you drink, it's almost impossible during a long run to take in the required fluid. Therefore, blood flow to the GI tract may decrease as much as 80%.

Under normal circumstances blood brings oxygen to your intestines and removes excess water. But without blood, the cells starve for oxygen and water pools in your large intestine. When this happens, you will first experience abdominal pain and cramping, then diarrhea ("runner's trots") and then possible bleeding.

To avoid "the trots" follow these precautions by avoiding the following foods:
1) Caffeine (including some energy bars and gels that contain caffeine)
2) Alcohol
3) Carbonated drinks
4) High doses of vitamin C
5) Lactose/milk products
6) Sorbitol and other sugar substitutes
7) Fructose, fruit products or juice, especially apple and grape juice that are high in fructose. Also, look for a sports drink that doesn't contain fructose. Gatorade is one of the few drinks, which does not have fructose.

In addition, try the following for a pre-run meal:
1) Bananas
2) Cooked oats (without added sugar)
3) Toast
4) Other low fiber carbohydrates

SIDE STITCHES
There is still a lot of research being done on side stitches, but what we do know about them is the following.
They can come from:
1) Dehydration... so drink water
2) Running too fast... so slow down
3) Eating too close to the start of your run... time your food better
4) Incorrect breathing... remember to breathe in and out through your mouth (not your nose) and stay relaxed. Think...dead fish.

If they continue to occur, here's what you can do:
1) It looks funny, but as you continue to run bend your knees. This is called "the groucho" (because you'll look like Groucho Marx). Do this for about 10-15 seconds, then run regularly, then keeping repeating for a few times.
2) Massage the stitch (while doing the Groucho, too.)
3) As you breathe out, step with the opposite foot from the side of the stitch. So if the stitch is on the left side, step with your right foot and breathe out.