Whether you consider dog backpacking a dog sport or just a great way to get back to nature with your pal, it will be good exercise and an enjoyable experience if managed with a little dog-sense.
"Do I look like a pack mule?"
What Breed is Best?
First off, be sure your guy is a mature adult before you hit the trail, particularly if you want him to carry a pack. Two years of age and over should be fine for most. If you want to get your year-old puppy acclimated to hiking, make it a short trip (a little longer than his typical long walk) and no pack for him.
Any sturdy sensitive brown dog (ok, just any sturdy dog) should be able to walk a good distance and carry his own food. A medium to larger breed such as a German Shepard, Labrador, Golden Retriever or a mix of those guys (kind of like me) would be good for dog backpacking.
The herding breeds are generally good for packing and hiking, but some (like Collies and Shelties) can't structurally handle much weight. Working dogs (such as Rottweilers, Malamutes and Saint Bernards) do the best with heavy loads as those breeds were developed to pull sleds or carts and carry packs. Keep in mind that a heavier load likely means they will be slower on the trail.
Some breeds are just poorly suited for dog backpacking. Long-backed breeds such as Bassets and Dachshunds come to mind. Not to mention those little fluffy, poodley guys.
If you have a good jogging partner, you know they would at least be a good dog for long hikes.
Also give your dog's coat some consideration for this type of activity. Some have coats that pick up burrs and and other "pieces of wilderness." Or, they have coats so thick they can't handle high temperatures (don't take your Husky out for a long, hot summer hike) or so thin they can't be out in the winter without a jacket.
Pack or Not?
Dog backpacking will take some preparation. You can't strap a pack on your dog and expect him to know what is going on. Start by putting it on him empty to get him used to wearing it around. Take him on a few walks or very short hikes and let him get to know his pack.
You can then begin to slowly add weight. Be sure to balance both sides of his pack as equally as possible. In terms of total weight, it should probably not exceed 15-20 percent of his total body weight, but watch him carefully. If he is not moving well, or struggling in any way, lighten his load. And, if you have any doubts about the right load for him while dog backpacking, consult your dog's Doc to be safe.
The Right Backpack
Just as for people, dog backpacking will be more enjoyable and manageable if your guy has good fitting equipment.
The best sources for backpacks tend to be pet stores, stores that specialize in outdoor activities and some specialty pet boutiques.
The best thing to do to ensure a good fit is to take your fella with you to the store. Find a pack you like and put it on him to test it out. Check the fit all around your dog to ensure a good fit without any rubbing or tight spots. Leave it on for a few minutes, then take it off and look for areas where it has altered his fur. If it's leaving indentations other than normal gravity marks, it's not quite right.
If ordering a pack online, you can go through this same test. You will just need to order two or three that look like they will work well. Keep the one that fits best and return the others for a refund.
Choosing a Location for Your Hike
The critical point here is to just ensure you will be hiking in an area that is dog friendly. Some State or National Parks don't allow dogs. And, of course, if there is a "no dogs allowed" sign posted, be sure to obey.
Otherwise, just be sure to keep your fella on the trail. Letting him wander through the woods is an invitation for tick infestation or an encounter with a snake or something else that can hurt him. Keep him nearby and enjoy your time together on the trail. Tell some stories - we are good listeners!
Trail Safety
When dog backpacking be sure to take along a few fundamental first aid supplies. You are well prepared if you also know some basic first aid.
Be sure to protect from fleas and ticks and get any ticks you find on your guy off right away. Be sure to check the pads on his paws regularly to make sure he is not experiencing any potentially dangerous wear and tear.
It may be difficult to keep your guy from drinking out of all the ponds and streams you encounter. Water has to have a very bizarre smell to keep a dog away, so he can get into something containing animal or chemical run-off that will be bad for him.
Bring along plenty of fresh water for him and try to have him avoid "nature's water" unless you are confident that it is ok. If you have a "goat dog" like me, he will probably be ok, but better safe than sorry.
You can consider purifying the water from streams. That also involves chemicals, so if you use a purifier it's a good idea to check with your dog's Doc to be sure it won't make him sick.