What are Plyo Balls and what can they do?
You see them everywhere on baseball fields and at tournaments: Colorful, soft balls that are thrown against walls and nets. These balls are called plyo (or plyocare) balls and it's hard to imagine modern baseball without them. They can be used in many different ways, which can make it difficult to categorize and use them correctly at first.
There's also the old, widespread stigma that all balls heavier than 5 ounces (the weight of a baseball) are the devil for your throwing arm - I was taught this emphatically.
Digression: Without going beyond the scope of this article, I would like to briefly address the question: "Are heavy balls bad/dangerous?". They are no more or less dangerous than a baseball. Just as you can overload your body with a baseball, you can of course overload your body with weighted balls/plyocare balls (just as you can with sprints, bench presses, skiing, jogging, crocheting, etc...) As unromantic as it may sound, the human body was not designed for a 5 ounce ball any more than the 5 ounce ball was designed for the body. It just evolved that way.
Heavier balls also do NOT automatically lead to a higher load on the arm (which is desirable in some situations - compare all other forms of training that are intended to induce physical adaptations). Roughly speaking, the stress caused varies depending on the weight, exercise and, above all, intensity(https://infogram.com/plyo-velo-to-mound-comparison-1h0r6rvkkkz72ek,https://www.drivelinebaseball.com/2017/12/plyo-velocity-weighted-balls-replication/ ).
Areas of application for Plyocare Balls:
Warmup
Plyoballs are a great training tool to make the warm-up more effective and efficient. The slightly increased weight of the ball allows the arm to enter into stronger external rotation (layback) even at lower intensities and to mobilize, stabilize and activate the arm in these ranges of motion. At the same time, the exercises and the balls contribute to an improved perception of movement, making higher intensities possible more quickly.
Physical adaptations
Although it is not the main aim of the Plyocare Balls, targeted training with maximum intensity can induce physical adaptations and train sport-specific speed strength.
Technical improvements
Paired with the "constraint drills", i.e. exercises with certain restrictions on the degrees of freedom, the plyoballs can be used to improve throwing technique very effectively. The different weights of the balls create an increased perception of movement. This allows the body to find its own ideal technique within the limits set by the exercises. Good movement patterns are therefore memorized and consolidated.
Armcare
The improved arm fitness and more efficient throwing technique alone protect the arm from injury as a first step. The next step is to use the Plyocare Balls to train shock absorption and arm deceleration. Example arm care routines can be found here, here and here.
If you would like to learn more about the use of Driveline Plyocare Balls, read Plyocare Balls exercises and how to incorporate them into your training.