what is bridge technique?

a bridge technnique can be a word that signals reenforcement is coming.  It is used to build the length of time an organism can tolerate before the reenforcer is delivered.  Essentially it is about trust.  A conversation if you will:  "yes that is right.  good dog... now hold on just a minute while I get your cookie, toy, get close enough to pet and love on you."  It is only effective once a behavior is learned and under stimulus control... Give the command/cue, the behavior occurs.  Over time you slightly delay the reenforcer once the behavior has occurred.

Read the clicker training section.  A "click", or even "yes" with your voice is a "bridge" (or marker) that tells the dog he did it right.
Pushing on your dog just creates resistance.  Why not take a clicker class or other positive reinforcement type class (lure/reward) that can help you learn to train without physically manipulating the dog.
You can find on at one of these sites:
www.clickertraining.com
www.peaceablepaws.com
www.ccpdt.com
Also, check out these sites - they have free lessons and videos:
www.clickerlessons.com
www.clickersolutions.com
www.clickertrainusa.com (videos)

Marker training is fun for you, and more importantly, fun for the dog, too.[]

I think you actually mean the "leg bridge"? Bridging in operant conditioning is something else

Anyway, the leg bridge is just a way to encouage a dog to down on his own so that you can reward that position. You kneel on the ground with one knee and use your other leg to form a "bridge" that is just tall enough that for the dog to go under it, he will have to get on his belly. You can lure him under with some treats, and give him more treats as he stays under your leg, on his belly.

My own trainer recommended this technique for our coonhound who just would. not. lay. down! She told us to feed him all of his kibble for all of his meals this way for a couple weeks, and it worked great. I started to say the word "down" as he was going under to get his kibble. After that, I removed the leg bridge but still would only feed him if he layed down on command. It worked out great. After just a few weeks of working on it, he downs like an ace now.

I was going to say what houndlove said!  In that context I would have understood "bridge technique" to mean using the crook of your leg or a low piece of furniture to help you lure the dog into a down with a food treat.

I would try shaping this behaviour though (rather than luring), keeping your hands off and encouraging the dog to offer the behaviour on its own will make training easier because you won't have that instinctive resistance there.... and it will help to build confidence.  Although it might be slow going just at first if the dog has been trained with other methods because they get a bit confused; they are used to being told what to do and shaping is the opposite of that.

This is for Houndlove and Chuffy.  Yes I was looking for an idea of how to create a bridge your dog would go under for a treat.  I understand...just picture Georgie going around or jumping over me completely.  I will give it a try for as long as my arthritic knees hold out.  Thanks for the explanation.

To mrv and spiritdogs,  I was looking for an explanation of a physical bridge made somehow and did get two posts answering that question.  Thank you also for your info.  And spiritdogs, I will link to those training help sites.  It's funny, this is the smallest dog I have ever owned by far, and the only one I could not entice or push (gently) into a down.  Of course, this is the first time I have not started with a puppy, but an adult dog and not had the benefit of knowing the previous owner.  Anyway, thanks.

Small dogs find the down harder.  Apparently.  So our old trainer told me and it does tally with my own experience.