Of course, safety should come first. Don’t ever leave your dog alone while on a treadmill! The same goes for tying your dog to it - I don’t recommend doing this as it’s just too easy for your dog to be injured or even strangled.
And you know how you start your own workout by warming up and then cooling down afterwards? You should do the same with your dog! Wait at least an hour after feeding your dog to put him on the treadmill to prevent bloat or twisted stomach. It’s also a good idea to limit water before and after a workout for the same reasons, as well as to prevent any puddles on the treadmill.
Take your time with this training. You want your dog to love the treadmill, not hate it. Some dogs may need a few days to be comfortable with the sound and motion of the moving belt, while others will be on there and looking like it’s no big deal almost right away.
One last tip for training on a dog treadmill: don’t ever give corrections on the treadmill. As I said, it’s important that your dog is completely comfortable with the machine. It’s also not safe for your dog to wear a training collar, such as a martingale, choke chain, or prong collar, while exercising here. You don’t want to risk hurting your dog if the collar was to get caught on anything! Instead, use a flat-buckle collar or a harness.
So while a treadmill shouldn't take the place of daily walks outside, it can be an awesome tool for giving your high-energy dog what he needs. It's also great for owners who aren't physically able to provide enough exercise for their pet. Properly train your dog to use a treadmill, and soon he'll be begging to go on it!