Have you spoken to a doctor more recently about your exertional migraines? New medication is coming out all the time for migraines. My partner has one prescribed for him that can prevent a migraine once he feels it coming on. If you can prevent the migraines then half the battle will be won. I'm lucky as my migraines are pretty mild in comparison so sometimes a couple of aspirin is all that's needed to prevent a migraine.
I found this web page
which talks about possible treatments for post-exercise migraines. Some of it could be beneficial to you, or at least worth bringing up with your doctor.This site
also has a heap of information about the condition.
If swimming doesn't bring on a migraine but walking does could it be possible that heart-rate isn't totally responsible? Unless you're swimming incredibly slowly usually your heart-rate will rise more with swimming than moderate walking (it does with me anyway, or maybe I'm just a crap swimmer!). Could a rising body temperature be partially to blame?
I second the vote for pilates. It shouldn't raise your heart-rate too much, but it will help you strengthen and tone your muscles. I also think some free weights, lunges, squats and sit-ups could help. If you build muscle you'll burn more calories at rest. That will speed up your metabolism even when you're not exercising and will help you lose more weight.
As to your second question, I often get a stitch while running. While there is still a great deal of debate as to what causes stitches, some people say it's because of the diaphragm helping you breath. It gets jostled a lot along with your organs and can pull on the ligaments. If you breath constantly on the same step it can cause a stitch.
Again the Tri Doc has some good advice on this issue
- Focus on the pairing of your gait and your breathing. Most runners breath every two to four steps and do so when one particular foot strikes the ground. Those who exhale when their right foot strikes tend to be most at risk of developing a side stitch. As the liver is dropping secondary to the force of the right foot hitting the ground, the diaphragm is simultaneously rising with exhalation. The result may be excess stress on the ligaments, causing more pain. By modifying your technique to exhale when the left foot strikes the ground you may be able to prevent the stitch.
- Pacing is very important. Ensure that you start slow and warm-up appropriately prior to pushing the pace.
- Side stitch is more common when running after eating. Allow two hours after eating to ensure that the stomach is empty before you run.
- Deep breathing with forceful exhalation may help.
- Ensure adequate hydration.
Good luck! Let us know how you get on.