The pitchLogic STUFFpL system can recommend up to three adjustments for each pitch in your arsenal. We recommend picking one at a time to focus on, setting a goal, and repeating the STUFFpL assessment for updated recommendations once you reach your goal.

One recommendation you might receive for breaking balls is an adjustment to your Arm Slot. Learn what Arm Slot is, how it affects your pitch, why pitchLogic might recommend a change, and how to make an adjustment to your Arm Slot below!

Arm slot is the angle that the pitching arm takes through the top of the pitching motion up to the release point. It is represented by the yellow arrow on the Clockface and 3D Clockface. Arm Slot is expressed as time on a clockface when viewed from behind the pitcher. For example, a righthanded pitcher would generally have an Arm Slot between 12:00 (overhand) and 3:00 (sidearm).

Arm Slot itself is one of the factors that STUFFpL uses to assess your pitch. Your Arm Slot changes the way a batter reads a pitch and can change how effective a particular movement profile may be. For example, a pitch with an above average amount of Vertical Movement can be especially effective if you are able to throw if from a low Arm Slot, since this combination is less common and unexpected for batters.

Your Arm Slot also has a big impact on what type of spin you can generate. For breaking balls, lowering your Arm Slot will generally raise your Spin Direction by the same amount. For example, if a right-handed pitcher’s Arm Slot drops from 1:00 to 2:00, the Spin Direction may move from 7:00 to 8:00. Spin Direction influences your Horizontal and Vertical Movement, which are key factors in determining how effective a pitch may be.

Changing Arm Slot usually has little effect on Speed, Spin Rate, or Spin Efficiency.

STUFFpL also considers how well your breaking ball Arm Slot matches with your fastball Arm Slot. If your breaking ball Arm Slot is noticeably different from your fastball, batters may be able to anticipate your pitch.

The pitchLogic STUFFpL system anticipates all these effects before making an Arm Slot recommendation.

pitchLogic is generally very conservative about recommending Arm Slot changes. Arm Slot is an aspect of pitching mechanics that is unique to each pitcher. For breaking balls, pitchLogic will only make recommendations that keep your Arm Slot close to your fastball Arm Slot.

A higher Arm Slot may benefit pitchers by emphasizing their Vertical Movement. This is most common for curveballs. Think of an overhand pitcher with a ‘12-6’ curveball.

A Lower Arm Slot may benefit pitchers by emphasizing their Horizontal Movement. This is most common for sliders.

In some cases, an adjustment in either direction may help by taking advantage of a pitcher’s ability to create an unexpected separation between their Arm Slot and Spin Direction. In this case, STUFFpL can help you find where your pitch will miss more barrels.

Finally, pitchLogic may recommend adjusting your Arm Slot to match better with your fastball. If the difference between your fastball and breaking ball Arm Slot is too great, batters may gain an advantage by predicting which pitch you are throwing. pitchLogic can help you find the best balance between creating great movement and being deceptive.

It may not seem intuitive, but Arm Slot is mostly determined by the tilt of your torso and shoulders, not by raising the arm at the elbow or shoulder joint. Still, you may be able to adjust your Arm Slot by visualizing a higher or lower release point and letting your body adjust.

pitchLogic will never recommend large changes to your Arm Slot, so these adjustments shouldn’t feel strenuous or unnatural. A larger change, such as converting to sidearm from overhand, may be possible but is something that should be carefully considered with a coach or instructor.