One of the best and easiest ways to determine if your dog's fit or if he could stand to lose a pound or two is the rib check. Spread both of your hands across your dog's rib cage and see if you can feel is his ribs. If you can, he's in good shape. If not, he many need to lose a pound or two.

You can also check your dog by sight. A fit dog's profile will have a clearly defined abdomen that is slightly tucked up behind his rib cage. Viewed from overhead, a fit dog will have something of an hourglass figure and you'll be able to see a waist behind the ribs.