Hamiltonstovare should always give the impression of the ability to have great endurance and stamina. They should be well muscled and never over or underweight. Obesity is just as harmful, if not more so, in dogs than a dog being underweight.
Obesity is linked as a clear environmental cause for hip dysplasia, especially for dogs under the age of 2. I make an effort to keep my young puppies thin for that very reason. The more weight a dog caries while it is developing, the more strain is put on those developing bones, joints and muscles.
A Hamiltonstovare that is working in the field can easily burn a lot of calories so they can look skinny from time to time, but that is only acceptable during hunting season and the hip bones should never be visible. Hamiltonstovare have a thick layer of skin over their muscles so ribs may not be visible on a thinner dog.
A Hamiltonstovare in correct weight should have visible front and rear muscles, they should also have a visible tuck on their underside. They should not have an extreme tuck like a sighthound, but it should be there but more moderate.
Above are two of my Hamiltonstovare (Raven and Rolo) who are at extremely healthy weights for the breed. I keep on mentioning muscle tone with this discussion of weight because it is critically important for all dogs regardless of breed. A dog can still be at a healthy weight but in poor physical condition. There are some dogs being shown now that are at healthy weight but severely lacking in muscle tone.
Conditioning is the act of making sure that dogs are as physically fit as possible. We utilize several things to obtain physical condition with our dogs. The main ones are free running, fetch games, and balance discs. Free running and fetch games are easily to duplicate in a yard and generally takes about 45 minutes or more a day.
Balance discs are a training tool that have gained popularity over the years and we've been using them for about 3 years. We first started using them with Rolo to build his core condition and saw dramatic results. The puppies started balance discs from the time they were able to walk. We use FitPaws equipment exclusively and primarily use the FitPaws bone, 24" balance disc and the PawPods. My dogs are trained to "step" on their own to step up on the discs and allow themselves to be manipulated as needed.
Keep your dogs fit and be creative with the thing you use to keep them fit.