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 Spin Efficiency. Learn what Spin Efficiency is, how it affects your pitch, why pitchLogic might recommend a change, and how to make an adjustment to your Spin Efficiency below!

Spin Efficiency is the percentage of Total Spin that contributes to creating Movement on a pitch. The higher the percentage, the more the ball will move up, down, left, or right. Only Backspin, Topspin, and Sidespin create force on the ball to make it move. Riflespin, also known as gyro spin, creates no lifting force on the ball and reduces Spin Efficiency. Pitches with a high Spin Efficiency are sometimes described as spinning true or clean. Pitches with a low Spin Efficiency are sometimes described as spinning off axis, tilted, or spinning like a football.

Four-seam fastballs typically have high Spin Efficiency - 90-100% is common. Two-seam fastballs often have somewhat lower Spin Efficiency - 80-90% is common, though higher or lower two-seamers may be effective for some pitchers. Cutters typically have the lowest Spin Efficiency of all fastballs and can cover a very wide range of values.

A higher Spin Efficiency will result in more Movement toward your Spin Direction. A pitch with 90% Spin Efficiency will have approximately 90% of the Vertical and Horizontal Movement of a similar pitch with 100% Efficiency.

Fastballs with a lower Spin Efficiency are more likely to create seam-shifted wake Movement. This type of movement acts at a 90-degree angle to Spin Direction and is usually more significant for two-seam fastballs/sinkers. In the case of a two-seam fastball, it tends to create more ‘sink’ if your Spin Direction is more horizontal or ‘run’ if your Spin Direction is more vertical.

Fastball speed usually goes up slightly with increasing Spin Efficiency.

The pitchLogic STUFFpL system anticipates all these effects before making a Spin Efficiency recommendation.

Four-seam fastballs will commonly benefit from having a high Spin Efficiency. This maximizes the movement due to spin and will result in more ‘carry’ for overhand pitchers, or more ‘run’ for pitches that emphasize Horizontal Movement.

Two-seam fastballs/sinkers can have a sweet spot for Spin Efficiency. Higher Spin Efficiency may help create more Horizontal Movement, but lower Efficiency can decrease Vertical Movement (for more ‘sink’). pitchLogic’s STUFFpL system can help determine which of these changes would benefit each individual pitch.

Cutters typically have lower Spin Efficiency than other fastballs. Each cutter is unique and may benefit from a change in either direction depending on Speed, Arm Slot, Spin Rate, and other factors.

If you are looking to increase your Spin Efficiency, you should think about keeping your fingers “behind the ball” when releasing the pitch. Don’t let your hand rotate sideways or you will get around the ball at release which will increase Rifle Spin and therefore decrease Spin Efficiency.

If trying to lower your Spin Efficiency, you can think of your fingers coming off the ball on release slightly to the side of the ball or shifting pressure toward your middle finger.