Make Your Serve Practice a Routine Much like Walking

Tennis players don't need to take walks for exercise or relaxation.  Instead of taking a walk I'd suggest you go to the tennis players version of the daily walk by taking to the court by yourself with a ball hopper full of tennis  balls.  Your standard 75 ball capacity hopper usually only holds 65 balls with the lid shut down on it so here is my suggestion.

Stand it up back toward the fence and proceed to serve to your target zones in the serve box.  After each round of serving four balls which is how many I usually hold in my hand for practice you can then do another round of drop and hit forehands and backhands.  The point of this is to make it an exercise both physical by movement and to also focus on your precision.  There is no stress to be found in this drill since even if you miss your objective per shot you are moving forward toward your goal of hitting a set number of balls per outing.  I usually make the goal to go through a minimum of 4 baskets or approximately 260 balls

For Tennis players this is a better alternative than just a walk down the walking path since you can get exercise and at the same time improve your skills.  I find it as peaceful as meditation.