One of the best ways to avoid injury, develop throwing muscles, and increase pitching machine to give your body down time.
Core Training for Pitching
As a pitcher, you can't forget to be focusing on your overall fitness, which will in the end help take some of the pressure off your arm. Particularly, if you focus on core work and other bodily strength training. If you're only developing the muscles in your throwing arm, they'll be the muscles that will experience the most wear and tear. If you can build a strong core, it can take some of the brunt work out of adding power to your pitch. A ball will work your core and arms at the same time, which links these muscle groups in your muscle memory. This will make you a more physically fluid player in the long run.