There are many factors that play into how long your dog should play or get exercise. Depending on your dog's age, health, and breed, they should get anywhere between approximately 30 minutes to 2 hours of exercise every day. Larger, very active, young dogs would lean more towards a couple of hours, while lap dogs should get around 30 minutes to an hour of exercise. Be very careful with elderly dogs or those who may have health problems. Exercising too much could be dangerous or even fatal for these dogs. Ask your veterinarian for more information on your pet and exercise.