top of page

Curveballs - Kids Shouldn't Throw Them, Right?

OK, here’s a baseball topic that I’ve been consistently pushing for the last 5 years but “baseball experts” won’t listen.

First, all coaches should read this blog post in its entirety. Being educated should be a major priority for all coaches, and really, all people.

Secondly, I’ll start with the punch line:

Curveballs create no higher risk for arm injury, strain, or pain, than any other pitch. Do the research – and I’ll provide some.

In a systematic review of curveballs as a risk factor, conducted by 3 medical doctors, first published in PubMed in August of 2013, the researchers aimed to evaluate the scientific evidence regarding the curveball and its impact on pitching biomechanics and the overall risk of arm injuries in baseball pitchers.

They reviewed ten biomechanical studies on kinematic or electromyographic analysis of pitching a curveball, as well as five epidemiologic studies that assessed pain or injury incidence in pitchers throwing the curveball.

They concluded that, despite much debate (as we see in youth baseball circles), the data does not indicate throwing a curveball creates an increases risk of injury as opposed to a fastball.

In another study, 5 medical professionals set out to look at the biomechanical comparison between fastballs and curveballs as a risk factor for shoulder and elbow injuries.

This study showed maximal glenohumeral (shoulder) internal rotation moment (most stress) and the maximum varus elbow moment (most stress) for the fastball was significantly higher than for the curveball. The same goes true for wrist flexor moment. However, the wrist ulnar moment was greater when throwing the curveball. When they say "moments" they're talking about points in time where stress and strain is high.

Their conclusion: the moments in the shoulder and elbow were less when throwing a curveball than when throwing a fastball.

Finally (I’ll stop at 3), 5 medical professionals, including Glenn S. Fleisig, MD, from the American Sports Medicine Institute, and James R. Andrews, MD (the highest profile sports orthopedic surgeon around).

The researchers set out to test youth baseball pitchers with an average age of 12.5 years old. Data was collected with a 3D motion analysis system – kinetic, kinematic, and temporal parameters were compared among the fastball, and changeup, and the curveball.

For elbow varus torque, shoulder internal rotation torque, elbow proximal force, and shoulder proximal force, the fastball produced the greatest values, followed by the curveball and then the change-up. The fastball also produced the greatest elbow flexion torque. Shoulder horizontal adduction torque and shoulder adduction torque were the least for the change-up.

Conclusion: elbow and shoulder loads were the greatest in the fastballs, and least in the changeups.

Now, I’m not saying you should teach your kids to throw a curveball. That’ll depend on their development, control with the fastball and changeup first, and many other factors. But I am saying you should be educated on your decisions, not just regurgitating what your Little League coach told you 30 years ago.

Any comments or questions, don’t hesitate to reach out.

183 views0 comments

Recent Posts

See All


bottom of page