Guinness is 6 years old and going strong. He still requires a lot of exercise each day, much more than Rosco or Honey. He does this by running after and fetching a ball, over and over and over. He never gets tired of it. OCD. So....for at least several hours a day we make sure he gets that exercise, when practical. Here is a short video of what he does when we get bored of toss it in a straight line.