Things that exist: dog treadmill

DogTread PZ1702 Medium Treadmill for Dogs

Establish a Regular Exercise Routine for your Best Friend. Treadmill training can give a dog a great workout regardless of weather or environment, allowing owners to maintain a consistent exercise regimen. It provides increased muscle definition, toning, improves vitality, increases life span and can help curb destructive behavior or excess energy often associated with the lack of regular exercise. Keeping your pet healthy is a key ingredient to a happy pet.

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