"Delayed Internal Rotation" revisited and elbow roll-in

Almost 4 years ago, I wrote an article that was sort of a spit-balled take on an arm action sequencing concept. Practically immediately, it was torn apart by Dr. Mike Marshall. I realized then that the article was poorly written. Part of that was the spit-ball nature of it, its kind of "thinking out loud" approach, but a big part was my wonderfully awful descriptions of and references to the kinetic chain.

Shortly thereafter, I threw a disclaimer at the top and promised to re-write the article. Well, there really isn't much point because, even cleaned up, I don't think the concept holds water.

Today, at Ron Wolforth's Pitching Central Ultimate Pitching Coaches Boot Camp, that exact article was mentioned in reference to an analysis of different types of lay back, what causes lay back, and how someone can have late forearm turnover and avoid the dreaded reverse forearm bounce.

It's an action that I've addressed before in my pitcher analyses. In my analyses (both professionally and on this site), I've drawn attention to when a pitcher decreases reverse forearm bounce by "picking up" his elbow. You can see this very well in my 2009 analysis of Brandon McCarthy. Back then, I described it like this:

It's hard to tell from this angle, but McCarthy's reverse forearm bounce might be exaggerated by some elbow flexion. By this, I mean that he picks his elbow up high enough that gravity plus natural elbow flexion - rather than inertia - appear to be causing some of the ball's downward motion. This view is inconclusive, but I don't believe his ulnar collateral ligament would hold up for very long if inertia alone caused a bounce that large.

You probably noticed that I was having trouble effectively articulating my thoughts about it. Chris Holt of Pro Bound USA in Clearwater, FL -- who didn't know I was in the audience -- has solved this problem for me by calling it "elbow roll-in".

With that term in mind, watch some of those McCarthy pitches again. Pay attention to his elbow and layback. While there is almost definitely an intertial lag component that helps with McCarthy's layback, the bulk of the layback was done by the way he rolled his elbow into position to lead his forearm.

This method of layback is something for which I've become a big proponent over the past 4 years (for a number of reasons that I don't have time to get into right now). I've needed a succinct way to describe it for some time, and I'm glad Chris was there to help me out.

McCarthy suffers another stress fracture

Jeff Wilson has reported that Brandon McCarthy has been placed on the 7-day DL in Oklahoma City with a stress fracture of his right scapula. Unbelievable.

Seriously unbelievable. Bones get stronger after stress fractures. It's part of the healing process sometimes referred to as overcompensation (or supercompensation). Bones respond to stress and stress fractures by growing thicker, stronger, and more dense.

This is the third diagnosis of a stress fracture in McCarthy's shoulder. Having been through this twice before, McCarthy's shoulder blade should be plenty strong enough to withstand two months of pitching, but it apparently isn't.


What is believable, though? I see a couple of possible explanations.

The original stress fracture from 2007 simply may not be healed. If this is the case, the cause is likely dietary, but it could be that the injury has never been given sufficient time to heal. Stress fractures often become pain-free well before they are actually healed.

Another explanation is that the problem is not actually a stress fracture. Soft tissue is much more susceptible to re-injury than is bony tissue, and the location of McCarthy's injury is a confluence of soft tissue that literally encapsulates the glenohumeral joint.

The recommendations here are running short.

McCarthy attempted a mechanical overhaul, but it doesn't seem to have accomplished its chief goal despite leading to a sparking ground ball rate at Oklahoma City where McCarthy has been excellent.

At this point, it looks like mechanics aren't McCarthy's real problem. If it isn't his mechanics, the culprit is one of the following: diet, strength/conditioning, and genetics.

Genetics, of course, can not be changed, but the other two can be addressed.

In addressing the diet, there are three things to watch for, and they all go hand-in-hand. The goal is improved bone density so the main focal points are calcium, vitamin D, and pH balance. I am not a dietician or a nutritionist, so I will stop short of making specific recommendations.

In addressing potential strength and conditioning issues that may be contributing to McCarthy's problems, a recently published DVD set contains just about everything anyone would ever need to know ranging from prehab and diagnosis to rehab and high performance.

You (and Brandon McCarthy) should check out Optimal Shoulder Performance.

[[Update: The evidence is apparently quite clear. This is, in fact, a scapular stress fracture. Someone who has seen recent video of McCarthy believes that McCarthy had fallen back into old mechanical habits.]]

Another post about Brandon McCarthy

If you're a betting man, you should know that the odds are good that this won't be my last article featuring the mechanics and health of the Texas Rangers starting pitcher Brandon McCarthy. As my favorite subject, his mechanics have spent a lot of time on my computer monitor playing forward and backward, in slow motion, and in still shots. As a result, I have a small tendency to see a little bit of McCarthy in just about every pitcher. Every once in a while I run into a pitcher whose mechanics have a lot in common with him. Meet University of Texas at Dallas junior Marvin Prestridge. [video] ...continued...
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Delayed Internal Rotation: Performance Implications

In the previous article Biomechanics: Ulnar Collateral Ligament, the discussion centered on what causes UCL tearing and how to prevent it. In one of my conclusions, I suggested the delay internal rotation until after arm extension. Now, I will discuss this concept in greater detail. Delayed internal rotation is the term I use to describe arm action in which internal rotation does not occur until after the arm extends. Done properly, this arm action allows the triceps brachii to maximally accelerate the forearm directly toward the target.
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