I walk my 4year old Lab nightly for about 45 mins. About once or twice a month, our walks are interrupted by him becoming very uncomfortable to the point where he is rapidly panting, stops walking, sits, lays down, cannot get comfortable, constantly changing positions. On these occasions, we stop, I calmly try to talk to him, gently pet him, until he is okay to walk again. The whole episode lasts no more than 5 minutes. Then we walk home like nothing happened. I have racked my brain trying to find the common thread leading to these episodes. The only thing I can come up with is that he ate within a relatively short time before walking. Maybe 30 mins or less before walking. Usually he eats at least 2 to 3 hours before walking. Is the problem most likely related to his eating, then walking shortly after? Do you think it could be something else?