Fastball: Arm Slot
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 fastballs 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 your pitching arm takes through the top of your 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). Unless you’re Tyler Rogers [https://pitchlogic.com/blog/2021/recreating-tyler-rogers-slider-with-pitchlogic] at around 5:00.
Item descriptionArm 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 it from a low Arm Slot, since this combination is less common and not expected by most batters.
Your Arm Slot also has a big impact on what type of spin you can generate. For example, lowering your Arm Slot will generally lower your Spin Direction by the same amount. 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.
The pitchLogic STUFFpL system anticipates all these effects before recommending a change to Arm Slot.
pitchLogic is generally very conservative about recommending Arm Slot changes to your fastball. Arm Slot is an aspect of pitching mechanics that is unique to each pitcher. If your Arm Slot is inconsistent, pitchLogic may give a recommendation within the range of Arm Slots measured during the session.
A higher Arm Slot may benefit pitchers by emphasizing their Vertical Movement. This is sometimes described as ‘life’, ‘ride’, or ‘carry’. This is most common on four-seam fastballs (FF) and cutters (FC).
A Lower Arm Slot may benefit pitchers by emphasizing their Horizontal Movement. This is sometimes referred to as ‘sink’ or ‘run’. This is most common on two-seam fastballs/sinkers (FT).
In some cases, an adjustment in either direction may help pitchers 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 may be most 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.