aggression on the leash

Question
Hello,
I have a 10-year-old golden retriever.  He was trained by my boyfriends parents, and now my boyfriend and I care for him in our home.  He is usually a very kind and gentle dog, but when we take him for walks, he is an absolute disaster when we see other dogs.  He barks, pulls, and I am not strong enough to hold him down sometimes.  We try to get him to sit and stay, but he is just too overwhelmed with the other dog that he won't listen to us.  We have recently been taking him to a dog park so he can socialize with other dogs, in hopes that he would be more welcoming and friendly when on the leash during walks.  So far nothing has changed.  He is completely diffrent with other dogs at the dog park, compared to on walks.  What can you suggest?  
Thanks for your time,
Megan

Answer
On leash reactivity is a really common issue. Frequently the dog is not aggressive, just conflicted and over-excited. Plus, having a dog on-leash really doesn't give him many options - either to greet the other dog politely with the appropriate signals, or to move away. I'm going to give you the names of the two best books I know to deal with this issue. One is "Click to Calm" by Emma Parsons and the other is "Control Unleashed" by Leslie McDevitt. Both books talk extensively about how to set up your training session, how important it is to keep the dog under threshold (once he's barking and pulling, you can't get him to learn) and how to teach the dog to have a different response to the other dogs. Sandy Case MEd CPDT www.positivelycanine.com