I think what youre referring to is bloat, which has nothing to do with exercise, it has to do with the way a dog eats. Some breeds are more prone to it, and elevating a dogs dish is said to help decrease the chances. Its mostly a matter of making sure your dog east his/her food slowly enough to give the stomach time to stretch out to hold the food, and not twist or suck in too much air while eating. I used to put large rocks in my dogs bowl so she had to seek out her food and it took her longer to eat, as she was prone to bloat and she would vomit her food back up in seconds when she ate regularly. Hope this helps!