I have noticed that if I go a few months without travelling, I don't really get thrown off. I think I automatically know what to look for and expect. Unless things change drastically. Travel requires alot of moving around on your feet. I definately don't move around like when I was say 25. But I still get around. I sometimes trade off pain for seeing what I need to see. If I start to get achey, from so much walking around, I just try to take more breaks. I found while in Canada, my legs were in pain including my ankles. I must have walked one of those days at least 3 or four miles including in the malls ect...
I found that by going to my hotel and using the heated whirlpool with a good rest, relieved alot of tension. I know we end up walking alot on trips. I kind of plan it that way to avoid over eating, under excercising and getting sloppy/lazy on the trip.