Exercise for dogs of any age is something that has to be worked out for each individual animal. What may be considered light exercise for a older lurcher will be quite strenuous exercise for a 2-year-old bulldog. My 11-year-old lurcher is still up for a regular game of ball. Being a chasing dog, ball catching is one of his main reasons for living, and I am loathe to stop this activity. My personal belief is that I would prefer my dogs to have shorter, happier lives than long, miserable, boring ones. However, I've adjusted ball throwing to make the best of his limitations, and prevent injury. I ensure he has loosened up well before beginning anything energetic. The combination of short, sharp exercise, which he enjoys, with lots of regular walking, keeps his muscles in good condition. Walks also give him the opportunity to sniff and mark, two of the other main pleasures in his doggy life.
Like I do with my lurcher, the best thing is to study your dog, find out what type of exercise he or she finds satisfying, and go with the flow, but realise your dog’s limitations and work within them. With the older dog, it's best to ensure you have your mobile with you, or that someone knows where you are, and when you're due back, in case you have an emergency. You'll probably make it back to the car carrying anything from a chihuahua to a spaniel, but a larger companion could prove a challenge!
One of the drawbacks you might find in keeping your dog fit and supple is, as it grows older, ending up with a pet whose legs are in fine shape, but whose hearing and eyesight are deficient. You then have an animal, which runs off at speed and pays no heed to your plaintive shout as it vanishes into the distance after someone it thinks is you. Sometimes these athletic older dogs are so quick, you need to “cut them off at the pass”! Keep to familiar walks as your pet becomes less able to identify surroundings; become more aware of its movements; and, when in strange territory, put your older dog on a leash to prevent it wandering and becoming confused and panicky.