I think I posted a reply to one of those other links, as I've wondered about this as well. I don't think it's the exercise itself that causes it, but more the stress/other factors involved with exercise such as heavier breathing, the use of blood sugar, dehydration/etc. There are TONS of changes that take place in the body while running (which is why it's so good for you), but those changes could also trigger seizures. Prior to medication, I had a few simple partials during running (usually when it was early in the morning - looking back I think I was sleep deprived).
I noticed on Monday after I had done a long, difficult race on Sunday that I felt a little off. I wasn't really sure if it was the medicine, or the exertion the day before, or maybe just being dehydrated from running. I made sure to drink extra water and made sure to take in enough food and I was okay. I think as long as you do what your body can handle, hydrate well, and eat properly, you should be okay with some running. Maybe try walk/running at first until your body adjusts to harder workouts? I always warm up with some walking prior to running, and always start slow and then build up speed as I warm up. It seems to help as the physiological changes between inactivity and activity aren't so great if you warm up first. I apologize for the long response - I'm slightly obsessed with running (if you couldn't tell by my screen name!) and it's something I've had to think about with the seizures.
I copied and pasted this list from a link that lists several common seizure triggers, and you'll notice that several of them can be caused by running - especially if you're sleep deprived/stressed/dehydrated all ready/etc:
Q - What are some of the factors that aggravate seizures?
A - While some people with seizure disorders will be able to recognize and avoid common triggers, there is no real way of knowing when a seizure will occur or what will necessarily trigger one. The following are common factors which may aggravate seizures.
- Rapid change in body temperature
- Over heating
- Dehydration
- Poor nutrition
- Hypoglycemia/hyperglycemia
- Sleep deprivation
- Depression and emotional stress
- Hyperventilation
- Not taking medication as prescribed
- Drug overdose
- Strobe lights
- Menstrual cycle
Note that usually it is a combination of several factors that increase seizure activity such as not sleeping well, eating irregular, stressed about school, and over exertion during an aerobic class may trigger a seizure.
http://www.pelinks4u.org/articles/conatser0609.htm