This is always a challenge for anyone who is health conscious and trains. While it’s difficult it’s not impossible with proper planning. Over my 16 year career as a professional bodybuilder I learned a lot on how to eat healthy and stay in shape while traveling 6 plus months of every year.
As a world champion professional bodybuilder nutrition is 70-80% of what I did. Training is the other 20-30%. After becoming a professional I had to learn how to stay on my nutritional program and workout while spending days and sometimes weeks on the road. From the beginning air travel was always difficult. Trying to eat healthy on a plane or in most airports is pretty much impossible. My solution was to bring a cooler bag and pack my food on the plane. I would bring precooked chicken, turkey, rice, potatoes, and pasta on the plane. As well as snacks such as fruit, jerky, and nuts. When you're on a 16 hour flight to Australia a fresh bag of all natural jerky is much better than cookies or candy!
Once I would arrive at my destination then it would become challenging. Language barriers and lack of healthy choices in restaurants means you have to think ahead and do a little planning. Very seldom would I just order from the menu. I usually requested my own unique meals. I learned that if you want something that’s not on the menu ask anyway. They usually have it. Depending on my schedule I would order extra meals to go so I would have the healthy food I needed.
Whenever possible I reserved a hotel room with a kitchen so I could prepare my own food (this is much less expensive than eating out). With a little effort and planning you can still eat healthy on the road.