Smaller breeds like the dog breeds we raise generally get lots of exercise by running around the house, playing with you and different toys. We have a large dog yard for our dogs, so all of our dogs can run and play together. If you only have 1 dog, they usually want you to play with them, that also helps them get more exercise, bond with you and your family, and just be an all-around more healthy dog. However, nothing compares to the good exercise your dog gets while being outside. It is good when you let your puppy outside to go the bathroom, that you leave them plenty of time to play, run around, and gets lots of exercise, and just be a normal dog! They love to run and play, especially outside! It is also helpful to allow your dog/puppy to get lots of exercise to help keep his/her energy levels lower while being inside your home.
Normally, if your dog is not getting enough exercise - they end up not wanting to go to bed on time, and they go crazy with lots of extra energy inside your house, so make sure they get the time they need outside! You can easily tell when they are done outside because they will want to come back inside with you, or they will go lay down because they have worn themselves out and are ready for a nap!