I wanted to do a newer article this week reviewing Bordelon et al. (2022) Peak Elbow Flexion Does Not Influence Peak Shoulder Distraction Force or Ball Velocity in NCAA Division I Softball Pitchers. The study involved 61 female NCAA Division I softball pitchers (average age about 19.9 years) who threw three maximal-effort fastballs while being tracked with a 3-D electromagnetic motion-capture system.  During the acceleration phase of the pitch (from top of the arm circle to ball release), the researchers measured each pitcher’s peak elbow flexion (how much the elbow bends) and peak shoulder distraction force (the force pulling the shoulder joint apart).  They also measured ball velocity using a radar gun. Then, using simple linear regression, they tested if more elbow flexion was associated with lower shoulder distraction force or higher ball velocity.
They found:
- Peak elbow flexion did not significantly predict peak shoulder distraction force (R² ≈ 0.023, P = .126).
- Peak elbow flexion did not significantly predict ball velocity (R² ≈ 0.023, P = .124).
- There was a significant positive relationship between ball velocity and shoulder distraction force (R² ≈ 0.343, P = .007) — higher ball velocity was associated with greater shoulder distraction force.
- Therefore, bending the elbow more (in this study) did not reduce shoulder distraction forces, nor did it increase ball speed.
Implications: The authors suggest that even though it might make intuitive sense that greater elbow flexion (shortening the lever arm) would reduce stress on the shoulder or improve pitch velocity, their data did not support this for collegiate windmill softball pitchers. Instead, shoulder distraction force seems more strongly related to ball velocity (i.e., the faster you throw, the higher the shoulder force) than to how much the elbow bends. This means coaching cues emphasizing elbow flexion alone may not be effective at reducing shoulder loading or increasing velocity in this population. The authors recommend focusing on other kinematic or kinetic aspects of the pitch (such as trunk and lower-body mechanics) when aiming to reduce shoulder stress or optimize performance. Lastly, they note that future research should explore additional factors beyond elbow flexion that influence shoulder loading and velocity.
Also…
Next issue I want to do a bit more of an in-depth look at strength training and how we could look to modify existing programs to be more softball pitching specific… and why. As a preview, here is a good post by Ben Griffin that will be a teaser.