I've had to travel to Phoenix twice in the last couple of months. I just try to not eat on travel days or eats nuts that I bring from home. Someone usually takes me out to dinner each night, but they seem to like restaurants where I can eat things I like. The toughest part is being in the actual office there during the day, where someone is always passing around cookies, candy etc. but I'm usually pretty good about trying to save my appetite for dinner.
Exercise though . . . I always have the best intentions but the time zone change and long days just wipe me out, so all of my plans to hit the gym in the am usually fall apart. Haven't had enough discipline to make that work.