Why do some athletes in running sports experience abdominal distress?

Abdominal distress in athletes who run is a very common problem. The areas that are usually affected are the muscles of the abdominal, and the intestines. Some runners experience very painful cramps if they drink water just before running, although this usually indicates that a person is dehydrated as well. If that's the case, you could also develop vomiting, gag reflexes, and cramps.

Another common problem of abdominal distress is not stretching before running (usually varies from how many miles you are going to run). Stretching warms up your muscles, which also include your abdominal area.  

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