If you know the phrase “bigger is better,” then you know it extends to your dog, too. There are many large and extra-large dog breeds out there, and each comes with its own particular care and training needs. Most large dog breeds are big for a reason — they were bred for a specific purpose or function. Some breeds were meant to be hunters, while others were bred to be guard dogs. Dogs with great physical endurance brought livestock or produce to market and even protected the farm from predators. Knowing your dog’s original purpose can be very important in determining not only the amount of exercise a dog will need, but also how much energy they expend in a day — and therefore how much rest they will need.