Research, and commonsense, indicate that older people get more exercise especially in bad weather if they own a dog compared to people who do not or who own a cat. Importantly, when the weather gets bad they still go out with their dog for a walk. I guess the dog needs it. A good dog owner will recognise that and brave the weather. Exercise is important for old people. Therefore should elderly people adopt a dog rather than a cat? There is also of course the social element. Dog owners are more likely to meet people while walking their dog than cat owners. This alleviates loneliness.