The AC Repair Man Called My Dog FAT

I have 2 Springer Spaniels, both weigh about 60 pounds. The AC repair man who came to the house last week took one look at them and said, "Boy you guys need more cookies". The truth is, they should weigh around 52-55 pounds, so now I'm going to put some serious effort into taking off a few pounds on RJ and Bennington. I think they'll feel better and have more energy. What low cal treats do you give your dogs, to keep their weight down. The boys walk the park twice a day, so the exercise is where it should be, but they get table food and treats all the time.