The Walk Away Game
Every time your dog is pulling on leash, he is trying to gain access to something he wants. If you allow him to look at that distraction while on a tight leash or worse yet, move toward it on a tight leash, you are rewarding a tight leash. Remember that: every time your dog pulls on leash, he is likely being rewarded for doing so. That means in essence, you are giving him a cookie every time he pulls!!
To prevent your dog from pulling on leash, you need to do two things:
1. Make sure that unwanted behaviour is not rewarded
2. Reinforce what you do want in place of pulling
To do this, you will teach your dog that a tight leash will not only no longer work for him, it will be a cue to return to you for reinforcement. From now on, a dog who charges in front of you will be an opportunity for him to earn reinforcement for coming back to you.
To play the Walk Away game, have your dog on about three feet of leash. Have your clicker and cookies ready and as you begin to walk with your dog, toss one of those cookies a foot or two in front of you and about three feet to the side. Keep walking as you toss the food. When you toss the food, your dog will predictably charge after it and will put tension on the leash. The second he does, say nothing and simply turn in the opposite direction from him. Don't wait for him as the leash tightens, just keep walking and let it tighten naturally. The moment he loosens pressure on the leash and begins to move toward you, click and reward.
If you play this game often enough, your dog will see see distractions in the environment as an opportunity to earn reinforcement from you. If you are consistent with this game, you will soon see him offer very attentive heeling when there are distractions present, in an effort to earn those cookies.
Once your dog gets really good at this game, practice it with different distractions. Play the Walk Away game with other dogs, people, toys, hydrants, anything your dog might find rewarding.
As you work through this game, you can even give your dog the chance to earn those environmental rewards. This is using Premack Principle to its best advantage. What you may see as distractions are actually powerful environmental reinforcers, so use them to your advantage. If your dog see another dog he would like to visit, ask for two or three steps of loose leash walking, whatever he can give you. Once he does, click and release him with OK, Go Play and allow him to visit the dog. Does your dog want to sniff a hydrant? Let him earn it with loose leash walking.
By using environmental rewards as reinforcers, your dog will assign even greater value to loose leash walking. He will see it as a way to GAIN access to the things he wants, not something that takes them away from him. Give him those powerful environmental reinforcers, but make sure he holds up his end of the bargain before you do. Remember, you do for me before I do for you!