June 2nd, 2009 | 
Author: If I have learned one thing from my psychology and philosophy classes, it is to recognize bad experimental design and flaws in logic. Chris O’Leary, in his pitching mechanics analyses, is subject to both of these problems and presents superficial and baseless arguments. This is disconcerting because many pitchers read his blog, fall for his arguments, and go about tampering with their mechanics in fear of his false prophesies.
The article of interest here is on the “Inverted W,” which is explained in the original article here. O’Leary claims to not like the Inverted W, in terms of a pitcher’s health, by way of three premises:
1. “It’s not what great pitchers do”
2. “It is what frequently injured pitchers do”
3. “It can create a timing problem [in a pitcher's delivery]”
Premises 1 and 2
In order to isolate a variable, which is necessary to conclude anything about causation or correlation, proper samples must be taken from the population in question. The population in question is pitchers, obviously, and the variable of interest is the Inverted W.
Now, finding causation in this situation is impossible, and I will grant O’Leary the charity that he is NOT making the case that the Inverted W CAUSES injury, but rather just correlates with it. Problem is, his design is still flawed…
O’Leary’s fault in methodology is in that he did not use a random sample, but rather specifically chose two populations to compare: 9 non-Inverted W pitchers who he considers great, and 6 Inverted W pitchers he considers injury-prone. Comparing these two samples tells us nothing about the Inverted W as correlating with injury, because the variable of interest is not isolated in any way. Multiple random samples are needed: a random selection of pitchers with Inverted W mechanics, a random sample from the entire pitching population (as a control group) and a random sample from the non-Inverted W group.
To isolate the Inverted W as the correlational variable, he would need to use a random sample of pitchers, the larger the better, and from that sample pick out those who throw with the Inverted W. From there he would have a population of Inverted W pitchers. Next, a random sample from the entire population of pitchers, or a random sample from all the pitchers who do NOT Do the Inverted W would be taken to use as a control and additional comparison group, respectively. He could then compare the injury rates of Inverted W pitchers to the rates of injury in the pitching population as a whole, or to the rates of injury for the non-Inverted W population. Then he could analyze the differences, to see if there exists a statistical significance between the groups in terms of injury rate. Finding a few percentage points difference in injury rates, would not be statistically significant, which would mean the findings could be attributed to chance as much as the variable. I would be amazed if there would be found any statistically significant difference between any grouping of pitching mechanic types.
I’ll give you an example of an experiment or argument using O’Leary’s design: One takes 5 injured submarine pitchers, and 5 healthy 3/4 armslot pitchers. O’Leary’s claim to the Inverted W being bad is analogous to making the claim that throwing sidearm in this example increases likelihood of injury, while throwing 3/4 does not. One can make ridiculous claims like this when you start with improper sampling.
Chances are, if one took a sample of 50 pitchers who throw with an Inverted W, we would get a wide variety of frequencies of injuries reported in their careers. One just cannot take a non-randomly sampled healthy group and compare them to an injured group and claim anything about the comparison. Its INVALID, and does not give any data as to causation or correlation (and correlation is not even a strong measure).
Language in Premises 1 & 2
On top of his methodological problems, O’Leary uses overly strong language which makes dangerous implications.
“It’s not what great pitchers do” – This statement is universal, and tells us that ALL, not SOME, great pitchers DO NOT do the Inverted W. O’Leary provides us with 9 (yes, 9!) pitchers he deems great and who do not use the Inverted W. If I counted correctly, there are currently 59 pitchers in the hall of fame. What of them? What of the other Cy Young Award winners and countless pitchers who have had strong 20 year careers?
The bottom line here is that he has not analyzed all these pitchers’ mechanics, and has no right to his claim that “it’s not what great pitchers do.” He also has not addressed whether or not great pitchers have pitched with the Inverted W, as I can almost guarantee that they have. Of the thousands and thousands of quality major league pitchers in the history of the game, undoubtedly every different type of mechanics have been used to achieve success. To take 9 pitchers, purposefully selected for their fit to his argument, and claim that from them we can generalize that all great pitchers do not do the Inverted W, is absolutely ludicrous.
Conversely, he gives us 6 Inverted W pitchers who are frequently injured and from that makes his argument that because these 6 have been injured, that all pitchers with the Inverted W will be injured. It’s a completely superficial and baseless argument.
Premise 3
The claim that timing is altered by the Inverted W, which is why it is inherently dangerous, is backed up by ZERO empirical data. No biomechanical analysis, no experiments, nothing. He takes what he feels is commonly held as proper timing, compares it to Inverted-W timing, and concludes that there is more distance for the arm to travel in external rotation, which increases chance of injury.
OK, so maybe that intuitively makes sense, but wheres the proof? Where is the data? Why should anyone believe that, when we have already shown that AT LEAST 2 of 3 premises leading to the conclusion that the Inverted W is evil, are completely baseless and invalid? I don’t have a problem with arguing from intuition, as long as the argument is done with soft enough language to let the reader know that he shouldn’t be interpreting the argument as fact or as causal. The problem is just that he isn’t backing up any part of his argument with fact. It’s just a bunch of pseudoscience, which unfortunately is leading pitchers to alter the way they throw, which may be leading them astray.
Go to Chris O’Leary’s website and look around, thinking critically. You’re going to find a lot of unsubstantiated claims dressed up in the fancy garb of analogies, comparisons, and bad experimental design. Whatever choice you ultimately make regarding pitching mechanics, make sure it is an informed one.
UPDATE: I want my readers to understand what I am putting forth here. I’m not a biomechanics expert, nor am I projecting my own view of the nature of the Inverted W. I don’t know what effect, if any, the inverted W has on a pitcher’s arm. This article is a review of his literature, and is presented to show the holes in his claims. I’m not here to make counterclaims, but rather to bring light to the fact that O’Leary’s argumentation and research is very poor. Do some additional research, and make an educated decision if you are looking to make mechanical changes.
Mr. Blewett,
I find myself agreeing with almost everything you write – O’Leary presents no statistically or experimentally valid support for his opinions – yet I think you are as guilty as he is in overstating YOUR case.
Just because O’Leary provides no valid statistics to support his opinions does not mean they are not in fact correct. We simply don’t know for certain. He presents no valid data to support his argument, and you present no valid data to support yours. Yet you dismiss O’Leary’s opinions with very strong language starting with with the title of your argument “Chris O’Leary’s Worthless Argument against the Inverted W” and throughout the body of your piece.
You state: “…I don’t have a problem with arguing from intuition, as long as the argument is done with soft enough language to let the reader know that he shouldn’t be interpreting the argument as fact or as causal…”
I think you’re guilty of exactly that. You would do us all a greater service by, instead of just tearing down Chris O’Leary and warning us not to listen to his ideas, you instead performed the analysis you suggest and report what you learn.
Think about it.
Gstrat,
I appreciate your close reading and critical assessment of my writing. I’m excited to know that I have a thoughtful readership.
In my defense: the difference, the reason why I am not similarly guilty, is in the burden of proof, which is always on the presenter of the argument. My critique of O’Leary was written not to intercede with my own ideas, but rather to attack his logical flaws and lack of evidence. Remember – I’m not making the claim that the Inverted W is injurious or beneficial, I am only making the claim that his argument was illogical and anecdotal at best, proving nothing about the status of the Inverted W. Seeing as how it is neither supported by logic or research, his argument really is worthless, hence the strong language. Had i substituted my own views, I would have been subject to the same evidential requirements – But I did not.
Could I have been more charitable to him? Yes; however I chose not be because I feel that he is developing a strong following of impressionable ballplayers who may be altering their path in the game by making mechanical changes that they may not need, which may (or may not) prove harmful. If I were presenting my own views in lieu of O’Leary’s, then you would be right, that I was acting just as he.
But you’re right – he could be right in his views, however, I refuse to take such wishy-washy views about life. If we have to agree that anything could be true, despite lack of evidence, then we open ourselves up to a life in which we cannot say anything for certain, because any number of unproven counterfactuals could be true. This view leads one on a very slippery slope to total solipsism. He could be right, but I refuse to grant charity to any theory anyone ever presents. This is why we have research and logic. If there is something that should be accepted as fact, then it should be the subject of strict research under valid methodology, and sensible, logical presentations.
I agree with Gstrat. I actually thought of writting a similar reply after reading.
While O’leary arguments aren’t good , most agree that Inverted W is bad for pitcher because of the stress on the shoulder and elbow.
I’m trying to find a argument that you may not consider worthless.
First of all, you say “most” agree the inverted W is bad. I’m not sure who this majority is, of whom you speak. Most people also believe in God, an afterlife, etc. with only personal justification for it. I don’t argue personal beliefs with people, it goes nowhere. If you still feel the W is harmful, then by all means avoid it. I just don’t want people changing themselves needlessly, and it may be needless.
I wrote a critical assessment of his argument, and make no claims about whether or not the Inverted W is bad – I have as little data on it as he, and have no intention of studying it, or doing statistics on the injury rate of pitchers who are an exhibition of it. But, I do have justification in breaking down what he has written. It’s peer review. Read both sides and believe what you want. It’s okay if you don’t side with me.
I am sorry I assumed you knew about the whole discussion around regarding the inverted W. Most researchers agree that the Invert W is bad.
I understand now that you “wrote a critical assessment of his argument”.
My point is he simply used bad arguments.
Fair enough. If you have any links to other Inverted W research, please send them my way. I’d be interested to read more about it. I realize I can get argumentative, but I really appreciate you reading my articles. Thanks, Dan
I agree with you that, just because certain pitchers had injuries and pitched with the inverted “W,” it doesn’t mean that the former is caused by the latter. However, simply saying “no, no, no,” isn’t an argument, either. Do you know of any pitchers who throw with the inverted “W” and don’t have injury problems? If you do, then you would really poke a gigantic hole in his theory.
Well, as you realize, my argument was to bring light to his poor methodology, not to blow the lid off the whole issue. If I had the time, I would dig through the big leagues to find the healthy Inverted W pitchers, who are invariably out there, but alas, my days have been long. I’ll make it a priority to start looking. Thanks for reading.
The inverted “W” and even elevating the elbow above shoulder height (after taking into account arm slot and shoulder tilt) will impinge and cause stress on the rotator cuff muscles. From a physical therapy standpoint, a shoulder injury is more likely to occur when the elbow is above the shoulder and the shoulder is externally rotated from an internally rotated position (like the inverted “W” position). It’s hard to argue with the research that has already proven this fact. In addition, why wouldn’t you want to look at pitchers that have similar pitching mechanics and have had long, successful pitching careers? Greg Maddux, Nolan Ryan, Roger Clemens, and Randy Johnson ALL keep their elbows below their shoulders, show the ball to 3rd base in “high cocked” position, rotate hips before shoulders, and use their large “core” muscles (upper legs and lower abdominal muscles) more than their arm muscles to generate power. I am teaching my sons these basic pitching mechanics and so far it seems to be working. Little League pitch count rules also play a big role in reducing repetitive injuries in young players.
First, understand that neither O’leary or yourself have any actual research showing a causal link between ANY type of pitching mechanics and injury. NO ONE in the baseball biomechanics field has a causal link between pitching mechanics and injury. Correlational research is the best anyone has done, and they have been weak at best.
Second, you’ve completely missed the point. O’Leary’s comparative argument is fatally flawed. Sure, Greg Maddux has nice pitching mechanics, but just because Greg had a great, injury-free career does NOT indicate that his mechanics play any causal role in his or anyone else’s injury status. The fact of the matter is, if you want to say anything about the role pitching mechanics play in injury, then you need to take a very large sample of pitchers and compare them to themselves as well as the major league average for injuries, etc. etc. (I explained this all in my article, which it appears you largely skimmed).
Third, how do you know Nolan Ryan, Roger, Greg and Randy use their “Core” muscles more than other pitchers? Let me answer: you don’t. That’s just anecdotal. There is not a pitcher out there who throws 90+ who doesn’t use his large muscles, rotate his hips before his shoulders, etc. etc.
Fourth, “stress” on the rotator cuff? Stress is pretty common on the rotator cuff, as every pitch causes it, no matter the mechanics. Stress will be there no matter how you throw, and in large, large amounts. That’s just the nature of the motion.
Please, email or fax me all of this research that you are quoting, I would love to see it. Chances are, it either doesn’t exist or doesn’t prove anything at all, much like the musings of Chris O’Leary, which I very clearly explained are flawed and anecdotal. The best research in the baseball injury field is on GIRD, which is one of the most widely agreed upon correlational precursors to injury, is still only CORRELATIONAL.
Of course more research needs to be done in showing a causal link between pitching mechanics and injury. I am just pointing out that from a medical and physical therapy stand point that what Chris O’leary states about the inverted “W” is NOT worthless. It has already been proven through lots of research that shoulder impingement occurs when the elbow is elevated above the shoulder and more stress is placed on the rotator cuff if it is externally rotated in that position. Yes, stress is placed on the rotator cuff every time a ball is thrown, but wouldn’t you want to minimize it by using better mechanics?
Ask any orthopedist or physical therapist if the inverted “W” position is impinging the rotator cuff and creating more of chance for an injury. I have some background in biomechanics, I have looked at hundreds of slow motion pitching clips, I played baseball, and I am a physical therapist so I probably am more qualified to discuss body mechanics or pitching mechanics than you. You state that Greg Maddux has nice pitching mechanics and I agree with you, but how do YOU know that? My point was that All those great pitchers that I mentioned use very similar pitching mechanics and that does translate into how much and when specific muscles are “fired” and timing.
Yes, major league pitchers all use their core muscles, but some make better use of these muscles. Some also create a larger hip/shoulder separation so that they are relatively using more of these muscles than their arms. Why do think Tim Lincecum can throw so hard for such a little guy? It’s not because he has stronger arms than anyone else, it is because he makes better use of his mechanics, flexibility, and larger muscle groups.
So when you say Chris O’leary’s argument is worthless, I will have to disagree with you. We should at least make use of the research that we have, even if some of it is correlational right now. Some of his information suggests to me that he has done his homework and checked out several professionals and biomechanical studies before have provided his advice. He has been correct in many of his predictions on pitchers and I don’t believe he has been proven wrong either. I am using some of his information, along with what I already know to teach my own kids so that their chances of getting injured may be reduced.
This is still neither here nor there, and I am really uninterested in arguing opinions and credentials. If you think you’re more qualified than me, congratulations, you’re one of many out there I am sure. Yet, there are tons of pitching coaches out there, myself included, who don’t need a degree in physical therapy to make pitchers better, and some of the best I know have no medical credentials. “Expert” is subjective, and going to med school and having a great understanding of the body still doesn’t make one an expert on using it. Millions play baseball and very few actually have a clue how to play it at even a moderate level. Theory from the training room is great, but it’s all too often not translated onto the field. And again, even if raising your shoulder causes impingement, this isn’t necessarily causing pitching injuries. And again, if you really have research on this, send it my way, because I don’t care to argue over thin air.
My article was extremely straightforward, and you’re arguing to me way beyond the scope of it. Honestly, if you read my post, there is nothing to argue – his language is absolutely too strong for his claims, his claims are based on improper research methodology, and he cites no research. Logically, it’s garbage, no doubt about it. Like I said in my article, I don’t claim to be an expert on the role of pitching mechanics on injuries, nor do I advocate for kids out there to change their mechanics based on my opinions. Nearly everything in human performance is based on educated guesses and past success. Nothing works for everybody, and I’m not nearly arrogant enough to tell you what you should teach your kids.
You are correct in stating that “nearly everything in human performance is based on educated guesses and past success”. Isn’t O’leary doing just that when he is looking at pitchers with past success and similarities along with other information that he has gathered to make an educated guess? He is not performing a research experiment and it is no different than you (a pitching coach) giving advice to ball players. What advice do you give players and do you have research articles to back up everything you teach them? I doubt it. The readers can take what they want from it to see if it works for them, or not. Nothing works for everybody, but at least he is looking at ways to try and prevent injuries in young pitchers.
You’re right, he is, but the difference is that the claims he makes are too strong. He says, “it’s what great pitchers do,” when in reality it’s just what a few great pitchers do. He oversteps his bounds. But yes, you are right in your other points, I just have problems with methodology and language, as he presents things in a very strong way, which causes more concern in ballplayers who might be reading, who might not be in need of any actual changes.
Interesting. While many of the HOF’ers are from the old days and thus video is not available, I did 1/2 hour of research and found video (or multiple still photos) of 25 HOFer’s (nearly half) and of that list ONLY Don Drysdale had the inverted W.
Grover Cleveland – No
Jim Bunning – No
Steve Carlton – No
Jack Chesbro – No
John Clarkson –
Dizzy dean – No
Don Drysdale – Yes
Dennis Eckersly – No
Bob Feller – No
Rollie Fingers – No
Whitey Ford – No
Bob Gibson – No
Catfish Hunter – No
Fergie Jenkins – No
Sandy Koufax – No
Bob Lemon – No
Jim Palmer – No
Gaylord Perry – No
Robin Roberts – No
Nolan Ryan – No
Tom Seaver – No
Warren Spahn – No
Don Sutton – No
Dazzy Vance – No
Rube Waddell – No