Yes Jimmy should be fine walking for an hour, as long as it's not too hot...it's almost November so Im sure it's cooling down. I take Ace and Summer on 40 minute walks and they get pretty beat too, sleep for a long time afterwards. I like it :) haha.
Once the summer rolls around again, depending on just how hot it is one hour may be too long. But waiting until the sun goes down in the summer time to walk for a long time may be better. I know when I try & walk Summer in the heat she lays down in the grass and won't walk after awhile lol.
my friend has a std doxie and she runs him every day. he's 3. in the summer, they run at 5 am, and they train till they are both up to 5-6 miles a day. as long as oyu work him up to longer walks/runs like you would with yourself he'll be fine.
I think you should take ques from the dog. If he starts to act tired, then you know it was to much, or to hot ect. I have Frenchbulldogs, Leeza when I first brought her home, she couldn't clear a block, she would be gong hoe at first, but soon slowed down and I would have to carry her. .Now she could walk all day as long as it isn't to hot. But I had to condition her over time. You got a hound, she wants to walk. If you were to stop, in time she would get out of shape, and then she wouldn't be able to go as far. Alot of people assume cause they took them out that first time and they got tired that they can't be walked very long. Dogs need to be conditioned at first. Some dogs are just physically unable, in a small amt of cases.
My small dogs love to walk and walk. I do take them in immediately though in the summer if they start plopping down in the grass and rolling around. It usually means it is getting too hot and they need to go in. I also take a water bottle with me so they can cool down. They drink some and if they need it they get some sprinkled or poured on them.
If your dog is young and is not overweight and he is acting overly tired after a walk, I would suggest having his heart checked out. A young, normal weight dog should not be acting overly tired after a normal walk. Could be heart issues.