Each pitcher has their own unique arm action. Like a fingerprint or signature, no two pitchers arm actions will look exactly the same. There are a very large number of degrees of freedom (essentially an infinite number of them) that go into determining what a pitcher’s arm action will look like, but for simplicity we group these arm actions into different movement patterns that are easier to understand. One example of this is grouping arm actions by length, i.e., how “long” or “short” an arm action is. By length, I basically mean how far an athlete “reaches back” towards second base with the ball during the delivery. A “long” arm action in this case would be one in which an athlete fully extends his/her throwing elbow towards second base during the delivery, and a “short” arm action would be one in which the athlete’s elbow remains fairly flexed up until ball release. Obviously, there is a whole continuum here and an athlete could have an arm action that is between long and short, but for the sake of discussion let’s just think about these two extremes.
A look around the MLB will tell you that there are pitchers at both ends of this continuum (and everywhere in between). Some guys, like Trevor Bauer or Lucas Giolito, employ very short arm actions (yet still throw very hard), whereas others, like Luis Castillo or Justin Verlander, have longer arm actions. If you’ve read my blog in the past, you probably heard me talk about how many aspects of pitching mechanics are highly individual. What works best for one guy might not work at all for another guy, and vice versa! As always, finding what works best for you will likely take some trial-and-error, and the arm action is no different. But are you just stuck wandering blindly through this trial-and-error process, or are there guidelines to follow in order to get started? Below, I’ll talk about one such guideline that can help you find your optimal arm action length.
Timing/sequencing with the rest of your delivery
The throwing arm must be in the right place at the right time in order for an athlete to throw hard and throw without pain. If the arm is late relative to the hips and torso, the rapid external rotation of the shoulder will place a significant load on the elbow (and specifically on the ulnar collateral ligament – the UCL). If the arm is early, the athlete will often end up “pushing” the ball towards home plate in order to compensate, which can also result in increased loads on the UCL, as well as lower ball velocities. It’s clear, then, that whatever arm action you choose must get your arm “on time”, or more specifically, get the arm to get into the high-cocked position at the time of stride foot contact.
As I’ve discussed with my trainer John Snelten at Prime Athletics, some athletes can maintain a very long arm action and still sync it up perfectly with the rest of their delivery. These are the Verlander’s and Castillo’s of the world that I mentioned earlier, and are able to repeat their mechanics to a very high degree of precision regardless of how far they bring the baseball away from their body. This takes a combination of elite athleticism and thousands of repetitions to achieve, and some athletes are able to pull it off. However, some athletes run into timing problems when their arm actions get long, and end up either pushing the ball or dragging their arm when this happens. Often times these athletes can benefit from shortening up their arm action using different constraint drills (as I will discuss below), as it allows them to time up their arm better with the rest of their delivery.
Ways of changing an arm action
So let’s just say for the sake of argument that you have been running into some timing issues because your arm action is long: how would you go about shortening it? There are a few different training modalities that could be useful in this case. One way of addressing this problem is by using overload implements (weighted baseballs or weighted plyocare balls heavier than a normal 5 oz. baseball) in order to shorten it up. The way that they work is summarized in this Driveline article, but basically the heavier stimulus makes it more difficult to get away with inefficient movement patterns. Throwing a heavier object makes it hard to extend the ball completely towards second base, for example, unless the arm times up perfectly with the rest of the delivery. Thus, weighted balls are certainly a valid approach to shortening an arm action.
Another approach involves using connection balls, first developed by the Texas/Florida Baseball Ranch. These can be used in a variety of ways, but essentially you can hold the ball with your forearm and bicep and prevent your arm from becoming too long (if you are trying to avoid that). The way they work, as Randy Sullivan discusses here, is that the bicep and forearm are forced to push against the ball in order to hold it in place as you throw, thus generating a shorter (and often times more efficient) arm path. One point of caution here, however, is that if an athlete is not experiencing any pain or any other issues with a longer arm action (i.e., if his arm action is still efficient), then forcing an athlete to adopt this shorter arm action could do more harm than good.
A third way to shorten an arm action is to do drills in which you have a short window of time to throw the ball. Catchers often have extremely efficient throwing mechanics overall, and in particular short and efficient arm actions, due to the constrained amount of time they have to throw runners out. The body often self-organizes to meet the demands of the task at hand, and in this case a catcher’s mechanics self-organize to become shorter and more efficient in order to gun down runners. We as pitchers can learn a lot from this in our drill work! By doing drills like quick picks or double plays, we are forced to get rid of the ball quickly, and inefficiencies in the arm action are often cleaned up as a result. Self-organization is a powerful thing!
The concept of arm action length has been an important one for me over the past few weeks of training. A few weeks ago, I was experiencing some elbow pain when I was throwing a bullpen, and after looking at some video I decided to try experimenting with a shorter arm action. I’ve began working with a connection ball and introducing more timing-constrained drills, and have seen pretty good results so far! Although I haven’t gotten back into maximal intent throwing yet, I’ve been able to throw harder on my 60%, 70%, 80%, etc. throws, which is always a good sign.
You might be able to see what I mean in the above video. My arm action was very long to begin with, and so the process of shortening it and making it more efficient is going to be a long one, but I can already see some fairly noticeable differences in comparison to what my mechanics looked like a few weeks ago. My arm does still essentially fully extend behind my body, but my elbow very quickly flexes and by the time of stride foot contact I am actually in a pretty good position to apply force to the baseball. Hopefully, these changes will continue to transfer over to higher intensity throwing when I work back into that again.
In the weight room, things have been continuing to go well. I’ve been working in a lot more speed-strength work on bench press and deadlift, and although I haven’t been able to measure my bar speed (unfortunately there is no tendo unit or anything like that at Prime), I’ve felt pretty quick at the weights I’ve been using (315 on hex deadlift and 135 on bench for sets of 2 speed reps). I’ve also been incorporating some anterior-loaded single leg squat and lunge variations for my lower body work. I worked up to 205×6/side on anterior loaded reverse lunges, and 185×4/side on anterior loaded Bulgarian split squats. I’m pretty happy with how this summer has gone in the weight room so far, and am looking forward to seeing how it translates to the field this season.
Image credits: https://www.southsidesox.com/lucas-giolito