KSH - I'm sorry you're getting such bad side cramps. They suck. I used to get them all the time and then they just kinda went away. I have no idea why. Now I almost never get them. As I type this, I've had a bit of an idea. Apart from the water thing that others already mentioned, maybe it has to do with pelvic stability while you run. If your hips are rocking up and down from side to side as you weight bear, your obliques would get over worked and maybe that's why they cramp. The answer, more core work. I especially like side plank and practicing hopping on one foot in front of a mirror. I'll give you more info if you like. PM me. Or.... I could be completely wrong.
I ran about 7.5 miles today with 4 x 1/2 mile hill repeats thrown in. The first one was hell. My legs felt awfully tired from my race this weekend. So I made some rules, if my form started to falter or I couldn't maintain a certain minimum pace, I would stop and just go for a light run, flattish. I made it through 3 really good reps. I wanted to do 4 to 5. At the end of 3 I felt pretty good and I thought that I would make it to 5 for sure. Then the wheels fell off the train on hill 4. It was hilarious. All of a sudden I went from invincible to shuffling. So I finished that hill and did the rest of the run on the flatter area at the top. I'm pretty happy with the day given the effort I put out this weekend.
Living life like there's no tomorrow.
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2007 Look Dura Ace
2010 Custom Tonic cross with discs, SRAM
2012 Moots YBB 2 x 10 Shimano XTR
2014 Soma B-Side SS