What’s a bird dog? A Movie, Nope! A Dog Trained to Retrieve bird’s. Could be! Watch something closely Maybe! The answers are okay but I’m looking for my bird dog. The bird dog is a bodyweight floor exercise that strengthen the core specifically, the abdominal muscles, lower back, butt, and thighs. Although it is called an isolation exercise, a lot is going on from head to thigh. As a bodyweight exercise, you need no equipment as your own body provides the resistance. It’s also easy to do anywhere, as long as you have a comfortable place to rest your hands and knees and enough room to extend both an arm and a leg. To get the balance right, all you need is a little practice.