I used to struggle with cramping a lot and I can't say exactly why the cramping stopped but it did. I played lacrosse in college and for the first two years I cramped and I mean really cramped. I changed my diet a bit and stopped drinking soda. I started drinking mostly water and that seemed to help a lot. I would recommend paying close attention to the foods you eat and when the cramping happens to see if you can find any correlation between the two. Every individual's body is different.

I never took any supplements like salt tablets or anything. I used to use Power Gel even when training which also seemed to help. That's it though.