Eyes ablaze with focus, the black-and-white dog heeds the start cue from her handler. She makes a jump, sprints up an A-frame, darts into a tunnel, shimmies through the weaves like a slalom skier, ...

Add Yahoo as a preferred source to see more of our stories on Google. Dogs of all ages and sizes need exercise. Without this physical stimulation, they will not live a happy life. However, finding the ...