Dan Blewett of Warbird Academy wrote a great post on the NPA-style holds that Steve Delabar popularized through Tom House and Jamie Evans, and I urge you to read it: Holds, Pitching Velocity, and Tom House Tennis Analogy.

Dan makes a TON of great points, one of which I wish I was smart enough to have realized myself when it comes to our Ballistic Reverse Throws (he even embedded our video):

Baseball pitchers internally rotate to throw a pitch. This means that three of the four rotator cuff muscles are eccentrically decelerating, not accelerating the ball. Thus, these three muscles – the supraspinatus, infraspinatus and teres minor – rarely get any concentric strengthening in the sport itself. This is not the case in tennis.

Rather, tennis players hit backhands, which is a concentric exercise for the scapula retractors, external rotators of the cuff and other back muscles. When Tom House talks about balance, he seems to forget that Tennis players get balance in their musculature from hitting backhands. Baseball players do not get this.

Conclusion: The backhand appears to strengthen the rotator cuff and back muscles in a way that the baseball throw cannot. This strengthening could be a large reason tennis shoulders resist injury.

The video in question is here:

Which remains one of our favorite training exercises and a major staple in our Elite Pitching Program.

Initial EMG Data

We took some initial EMG data on the NPA-style holds with athletes who previously trained under the NPA Velocity Plus program, and what we found was fairly interesting:

• Holds do indeed have similar levels of muscle activity (per %MVIC) in the posterior shoulder and rotator cuff area as compared to weighted ball throws
• Wrist weight exercises have a higher level of muscle activity (per %MVIC) in the posterior shoulder and rotator cuff without a significant increase in middle deltoid activity
• Ballistic reverse throws are about as good as holds and also do not engage concomitant internal rotation (a big plus for both exercises)

Most training programs seek to reduce middle deltoid activity, as engaging that large part of the shoulder can aggravate impingement issues in the shoulder. Holds seem to do better than I thought they would, but there is still the real possibility of the "negative blend" of contracting the medial forearm and "pushing" the baseball - not movement patterns we want to mimic at all in the pitching delivery, while we want that aggressive shoulder rotation you see in ballistic reverse throws and we want the aggressive pronation hand speed in the wrist weight throws!

The study isn't yet complete, but the initial data definitely seems to support my initial argument as well as Dan's.