In the middle of your run you might start to feel a sharp pain in your ribs. This could be a cramp. You have Intercostal muscles between your ribs that's protecting your lungs. If you start your run too fast, this can cause cramps throughout your body. What you can do to prevent this is work into your run. Do a slow warm up to let your body adapt, to the workout that you're about to do.
This can help to prevent that sharp rib cramp that you might feel during your run. If it's really uncomfortable you can pull over or slow down your pace, maybe walk, maybe do a slight jog and just stretch. Maybe just open up the side where you're having that cramp, or you know if it's the other side just wherever that cramp is, just reach up, do a stretch, breathe into it and I guarantee it will go away.