Driveline Articles on Spin Rate

Spin Rate: What We Know Now

Spin Rate Part II: Spin Axis & Useful Spin

Scaling Velocity & Useful Spin in Offspeed Pitches

Pitch Grips and Changing Fastball Spin Rate

Spin Rate Tracking Technologies

Trackman Use at Driveline Baseball – How We Validate Our Equipment

Rapsodo, Trackman, and Pitch Tracking Technologies – Where We Stand

Diamond Kinetics PitchTracker, Rapsodo, and Pitch Tracking Technologies

Spin Rate Research

The Effect of Fastball Backspin Rate on Baseball Hitting Accuracy (Open Access)

Authors: Higuchi, T; Morohoshi, J; Nagami, T; Nakata, H; Kanosue, K

This study aimed to examine the effects of hitting pitches with the same velocity but different spin rates. Pitch velocity was set at a standard 87 mph, while the pitch changed between 1800, 2400, and 3000 rpm. Balls were placed into the pitching machine with the same seam orientation, and each batter took 30 swings in total with a 10-minute break halfway. The spin rate was changed each pitch. The movement of both the bat and the ball were tracked using two synchronized high-speed cameras.

The researchers found a significant positive correlation between ball backspin rate and impact Z deviation. Essentially, the higher the spin, the further the ball ended up from the sweet spot of the bat. Batters were most successful for the 2400 spin-rate pitches; pitches in the 1800 range found subjects to mishit by swinging over the ball.

This study shows the effect that spin rate can have on a hitter. It’s great that speed was controlled for because spin rate is often discussed as a stand alone effect. However spin is related to velocity, which is why we often discuss spin in the terms of Bauer Units.

Note: This study was published in 2013. We now know that 2400 rpm for a fastball is near the highest that will be seen in MLB.

The Relationship Between Finger Strength and Spin Rate of Curve Balls Thrown by NCAA Division 1 Baseball Pitchers

Authors: Woods III, G; Spanoil, F; Bonnette, R

This study examined the relationship between the curveball spin rate and finger strength of fifteen NCAA D1 baseball pitchers. There has been little research on spin rate, and this study asks an interesting question in regards to what factors relate to spin rate.

Previous research has suggested that the amount of spin is related to the amount of break of a breaking ball. In theory, spin may be related to the amount of finger pressure applied on the baseball.

The researchers collected the following metrics: index pinch strength (IPS), middle pinch strength (MPS), total pinch strength (TPS), and spin rate for curve balls (SRC), measured by RevFire*.

Statistical significance was found between index pinch strength and spin rate (r = -.61) and between total pinch strength and spin rate (r = -.47). The results show that index pinch strength, as well as total pinch strength (index and middle finger), is significantly negatively correlated with spin rate of a curve ball.

This study specifically found that spin rate has a inverse relationship with finger strength. This means that it was not the strength that influenced the outcome; rather, it was the controlled amount of grip pressure that may ultimately determine spin rate.

The study did not take into account grip factors and it may be more likely that each pitch was simply a ‘breaking ball’ not a curveball. Regardless, some may find the relationship seen in this paper to be surprising. (There, of course, are differences between pressure applied to the ball when thrown and to a strength measure.) While spin rate is an important measure, it is not the only important factor for an offspeed pitch to be effective.

Lastly, this research speaks to the difficulty in throwing offspeed pitches and the amount of finger dexterity and sensitivity needed to apply just the right amount of pressure.

*Note: RevFire is a ball with a sensor in it that can measure spin rate. It is no longer on the market. At Driveline, we had brief testing with the RevFire but nothing substantial enough to validate its numbers. So, this study may change under different measurement tools.