Traveling, while good for the soul, presents a certain amount of challenge to the body. One’s best efforts to eat good food can be stymied when all the choices come from 7-Eleven, fast food, or rest stop vending machines. Determination to exercise can fade after eighty gazillion miles of driving. I have two suggestions:
First, do something. Pick the best of the bad options. Maybe there is no real option for lots of exercise, but we can always at least stretch; it may even happen automatically when we at last have a chance to stand up. Even gas stations sell nuts and water, which can get us through until we find real food.
Second, don’t sweat it. Soak up the good parts of what is happening. See the sights. Taste the local cuisine, whatever it is. Be present.