Stomach pain during and after a run???

Hi everyone,

Maybe someone can help me or offer any advise based on their experiences.

I've been running for over 2 years now, I've been getting stomach pain everytime I would drink water or gatorade during or right after my runs.  I've been ignoring it for so long since I was only running 5Ks and 10Ks, so often times I wouldn't drink anything until I'm done running.  I would wait about half hour after my run before I would drink or eat.

Now, I'm training for my half-marathon in May or June.  I know I won't be able to sustain my good running condition if I don't hyrdrate myself during the long runs.  Last Saturday, I ran 8 miles and I tried having a little sip of water after 1.5 miles, then a small sip after another 1.5 miles.  Then I had another after 2 miles, 2 minutes after that my stomach started to hurt.  I know it's not a cramp, the pain is like a stomach pain when you're having a diarhea kind of pain.

Last Tuesday I ran 5.5 miles, didn't drink any water at all during the run, I had a little bit of water right after and my stomach hurt again.  I also tried gatorade, energy spray, shot blocks..but I still get stomach pain.  Are there any specific stretches I could do to prevent this..something...anything...???

I'm wondering if any of you experience such pain like this and if anyone has any recommendations on how to prevent the stomach pain so I could run my half-marathon properly hydrated without the pain.

Help!

I used to get stomach cramps. I'm called the 'camel runner' because I run Arizona 10k's without ever taking a drink. Last summer I ran a 5k w/my husband.. had a small drink of water afterwards.. and then ran my 10k- no water. That was alright, but I did get some stomach cramps early in the race but then went away. 

I'm not sure of the cause, but what I've found really helps is to not eat any food before a run. After waking up, I drink about 4oz water, do sit-ups to burn my abs & then run 5mi. I think (but not sure) doing sit-ups & not drinking right before have helped stop the cramps. I do drink lots of water after, throughout the rest of the day, & before bed. It sometimes feels like the pain comes more when I'm constipated. I deal w/ that by taking senna (6-8 Senokot tablets) before bed. I wake up not constipated.. no diarhea either. I don't take it the night before a race though.

Hope this helps some. :)