They do have to work their way up to a distance walk, but I have also found out it depends where they come from and how thick their coat is, we got Jasmine from Oaklahoma and when we got her, she had a very thick coat of hair from being in the freezing cold and then coming to SC, she is starting to do better as she is losing her coat. But when we first got her she was panting like crazy. We thought it was because she was nervous coming to new surrendings and this may have also been true but she kept panting and as she is losing her coat she is doing better. Good Luck, sorry if I was not a lot of help, just telling you my experience.