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Weighted Balls: Questions, Kinetics & More.

This article will address the many questions, facts and thoughts surrounding weighted balls and the mechanisms behind their success. I will also discuss their use, risk, reward, potential and practicality. I am not your doctor and you should consult with yours before doing anything mentioned in this article. Before we attempt to answer all of these questions, a quick preface:

Arm Health and Velocity Development are NOT Mutually Exclusive!

Does that statement stir up some questions in your mind? For many years, it has been commonly assumed that as throwing velocity increases, so does the risk for injury. However, that is far too simple and much too generalized of a statement to be considered true. Truth be told, often times increased velocity is coupled with a looming injury. However, with proper programming, training and recovery modalities the athlete’s injury risk does not necessarily increase, as one would traditionally assume.

For instance, if Pitcher A begins aggressive weighted ball throws without a proper biomechanical screening or without the proper base and maturity for it, then yes, the possibility of injury can certainly increase. On the flip side, if Pitcher B begins a well thought out and individualized weightlifting and weighted ball regimen that is coupled with mobility and recovery protocols while improving soft tissue quality, his chance for throwing injury does not necessarily increase as the it would in the first scenario. Conversely, more often than not, his durability, fitness, workload threshold and performance output will likely increase.

Velocity can increase from any number of contributing factors such as weight gain, weight loss, puberty, nutrition, weighted ball training and countless other ways. For someone to think that weighted balls are simply the biggest cause of significant velocity gains or even injury is incomplete at best. Weighted balls are just one element of training to be incorporated into a comprehensive program to benefit the athlete. Now, lets look at many of the surrounding questions regarding weighted balls, their practicality and their place in training.

What is The Overload Principle?

The overload principle states that the body will adapt when greater than normal forces are applied to it. To continue improving over a period of time increased stresses, load progressions and aspects of periodization are required. The body is the perennial adaption system the world has ever seen and is designed to be pushed to its limits.

Pitchers pushed to their bodies’ limits? Red lights often start going off in peoples’ minds when they hear that overhead-throwing athletes should be trained like other elite athletes. This is likely due to the decades old dogma that has emerged from simply not reviewing the research that is readily available today. Simply put, the overload principle is a basic concept stating that in order to get stronger, the athlete must increase workloads and volume of training. Mind you, in no way at all am I advocating aimlessly throwing around absurd weight without programming, but I am suggesting that most pitchers should in fact train to optimize athleticism and simple "arm care" like I’s, Y’s and T’s wont do that for everybody.

Why use the overload balls?

A regulation baseball is 5 oz. An overload ball is any ball with a weight above 5 oz. The stigma often surrounding overload training is that it is harmful. Unfortunately, those thoughts are rooted in unfamiliarity and naivety. In no way are those thoughts in line with today’s understanding of exercise physiology, kinesiology and the biomechanics of sport. Folks have long assumed that throwing heavy balls will get you injured, mess up for your arm action and negatively affect your ability to command the ball.

Why do folks think heavier balls increase the chance of injury? Well, maybe they assume that throwing a 5 oz ball is bad enough for the arm so throwing a ball with more weight must mean greater work loads which means more stress (to the elbow and shoulder) and more stress must mean more injuries. That line of thinking may be useful at times when dealing with basic objects, but the human body is far more complex than that. When well managed added loads and stresses are imposed on the body positive adaptations occur. When tissue types (muscles, tendons, ligaments, bones) take on added stress they respond by adapting and increasing their tolerance and stress intake threshold. As you read above, some aspects of the overload principle are also present in varying degrees depending on the movement and drill. As an example, if you wanted to increase your bench press numbers, you would progressively increase the volume and intensity of your training to prep for that lift. As a result, your tolerance levels and stress threshold will increase as will your strength output and fitness levels. This is obviously a very basic example, but nevertheless illustrates the point. Throughout the article, I will mention that overload balls also help map a more efficient arm path than a traditional 5 oz baseball can. But how does that occur? First, we have to understand the kinematics and biomechanics of throwing. The action of throwing is the summation of adequate and efficient sequencing and force production through the kinetic chain. Due to the nature and high intensity of a maximum velocity throw the body moves through positions it could not normally get into and forges forces, velocities and torques that are not normally accessible to the body. The goal is to transfer kinetic energy (through the original site of ground force production which is anchored by the foot) up and through the body and then channel that energy into the ball and it’s flight.

Back to how overload throws help map a better arm path: When an athlete throws a heavy ball and moves at a high intensity, his body is forced to move the surplus load just as it would a regulation baseball. The body is then required to find a more efficient and suitable route to move through the delivery without allowing an element of rhythmic disconnection. The execution of the overload throw requires the body to dynamically recruit and increase neuromuscular capabilities. The heavier weight of the ball lowers the velocity of the throw, thereby decreasing much of the stress the body accepts. Throwing an overload ball trains rate of force production and organically creates and unlocks previously untapped ranges of motion, such as a deeper forearm layback (glenohumeral external rotation). When the thrower is in that layback position, the expressed weight of the ball (during the high speed of the throw) adds stress through the end range of motion, which is the mechanism that allows for greater movement through those angles, and the expression of stability and/or strength through those end ranges. When a heavy object is placed in an athlete’s hand and he throws at a rapid rate, the arm will route for efficiency and maximum output, thereby cleaning up any glaring inefficiencies that may have been developed with a regulation ball. The process of improving arm action is not a quick fix, but is a step-by-step process in the right direction. Allowing the weight of the overload ball to take over is important because allowing subconscious motor learning and control to be the guide in arm mapping is far superior than conscious thoughts or external verbal cues that are nearly impossible to replicate at maximum effort.

Why use the underload balls?

An underload ball is any ball that weighs less than 5 oz. The velocity of the throw is often higher than regulation and overload throws. Most folks think that while the overload balls train arm strength, the under load balls train arm speed and that is not really off base at all. The general stress loads that are accepted by the body during underload throws occur during the latter phases of the throw (as compared to overload). Some of the physiological mechanisms that occur during those phases are glenohumeral internal rotation, elbow extension and forearm pronation. The truest forms of elbow extension routinely appear during elite level throws, which means incredibly high elbow extension angular velocities take place. In case the idea of angular velocity is not very clear, let me offer this example: angular velocity can be measured in a pitcher’s peak elbow extension during a throw, whereas, linear velocity is measured by the speed and direction of the pitch. The peak angular velocity of glenohumeral internal rotation can also be trained using underload balls. The underload throw is speed based and thereby demands and imposes more stress on the deceleration patterns of the arm. We know that imposed stress is how the body adapts and, in turn, is able to produce greater forces and velocities.

Will weighted balls affect my command?

First off, lets make this clear: Throwing strikes is not all mental and is not only a result of “ repeatable mechanics”. To think that it is plausible for someone to consistently throw a baseball at max effort with the same exact metrics (release height, distance to plate, foot strike position, etc) is absurd. Obviously, there is a psychological and physiological aspect that goes into throwing strikes, but throwing strikes is the summation of many components all falling perfectly into place. Proprioception, which is somewhat similar to kinesthetic awareness, is the driving force behind coordination, athletic performance and, for our purposes, throwing strikes. Ever wonder how guys can throws strikes on command without training for it? Or how they throw from different arm slots without training or go to the basketball court randomly and have a ridiculously high percentage of made shots? Often times, those guys have heightened levels of proprioception.

We know that weighted balls promote proper arm mapping and efficient deceleration patterns. We also know that the more efficient and “clean” a delivery is, the easier it is for the ball the find the zone. Often times, the intent to throw hard and efficiently positively affects one’s ability to throw pitches in the zone. The cleaner an arm path is and the more efficient one’s delivery can be, the more likely they are to throw strikes. So, will weighted balls affect your command? Weighted balls help promote a positive and efficient arm action and those are both major contributing factors to frequently throwing strikes. Weighted balls also positively affect proprioception levels due their nature of forcing the body to adapt and adjust. It is pretty amazing how so many guys begin to throw weighted balls (plyocare balls included) and end up saying how surprised they are because they’re throwing more strikes than ever before all the while practicing throwing strikes significantly less than before. Hmm…

What is the difference between weighted baseballs, plyometric medicine balls, plyocare balls, etc.?

First off, there are many different brands of these types of balls and the quality of each brand differs greatly. We recommend using Driveline Plyocare Balls and/or Oates Specialties TAP Balls. Weighted baseballs are just that, baseballs of differing weights whereas, plyoballs are handheld, sand filled mini-medicine balls that don’t provide the same feel since most are durable rubber like balls with some element of squishy-ness. I’ve stated in another article and earlier in the post that I believe there is some sort of athletic cognition (to say loosely) that allows athletes to be aware of themselves in space, cognizant of relative positioning and overall kinesthetic awareness. The differing textures of these “plyoballs” (a term popularized by Kyle Boddy and Driveline Baseball) allows the athlete to differentiate from the feel of a baseball in order to help reinforce the intended movement patterns without naturally defaulting back to the ingrained patterns of throwing a baseball. Plyoballs are often used during drill work (constraint drills, partial throws, etc.) but they are great for solo training too. If you’re alone and need a training space, all you need is a wall and some plyoballs. Plyoballs (and weighted balls in general) help promote and reinforce motor learning, effective kinetic sequencing, neuromuscular capabilities and many other benefits. I could not recommend a more useful training tool for guys who often work extra and/or alone.

What if I already throw hard?

When it comes to programming weighted ball regimens, it’s so important to account for all of your physical and/or limiting factors like age, training history, mobility deficits, motor development and many others. A 17 year old who has been up to 94 will certainly have a very different program than a 20 year old JUCO guy looking to make a big push and break into the next level. Yet, does that mean that the 17 year old who is up to 94 shouldn’t do weighted balls? Absolutely not. If the 17 year old is also recovering well, following arm care protocol, lifting/conditioning in some capacity and operating under a comprehensive and long term program to build a foundation, there is no reason why he shouldn’t begin a weighted ball program. There is clearly more of a window for velocity improvement (percentage wise) with lower velocity arms, yet high velocity arms can still make worthwhile gains and work to maintain and hold their current velocity. Meaning if you’re a 75 guy making an 8% velo increase (6MPH) is much more likely than a 91 guy making an 8% velo increase (~7MPH). Also, when managing high velocity arms it’s important to consider being more conservative with your weighted ball regimen than a senior in high school topping 84 trying to play in college. If you’re a 95 guy, proper weighted ball programming becomes even more important due to the underlying risks vs. rewards of adding a tick or two to the gun from a poorly organized or overly aggressive program. Now, if you are a high velo guy already, getting on a proper weighted ball program with good coaching, could very well be the component that saves and/or furthers your career by separating yourself from the pack even more (from a velocity and durability standpoint).

Where do we draw the line between positive adaptation and overuse?

The fact that weighted balls impose greater stresses to the tissues and structures of the arm is not necessarily a bad thing. However, those added stresses demand adequate load progressions and management. Positive adaption is not exclusive to connective tissue- in fact; positive adaptation can take place in ligaments and tendons too. Increased physical stress can produce some really beneficial adaptations in the tissue, but can also be very injurious if it exceeds the biological threshold. A specific movement of a particularly high magnitude could exceed the predetermined threshold or it could be exceeded due to chronic mismanagement of loads and recovery. There is no set marker that draws a clear line between overuse and positive adaptation simply because every body is different. Avoiding deterioration of tissue quality and fitness levels are the key components to avoiding long-term tissue breakdown. When examining the relationship between overuse and adaptation, one must consider the SAID principle. SAID is an acronym for Specific Adaptation to Imposed Demands. According to the SAID Principle, the body makes specific adaptations to the specific demands that are placed on it. So, as a very basic example, if you want to be better at throwing at high intensities, you should adequately prepare and train the body to do so by practicing that at high intensities. Another example: there are many people who run half marathons. Often times when people don’t train before hand and get injured during the race, yet there are folks who run many half marathons and avoid serious injuries due to proper training. The latter group simply runs long distances beforehand and allows the SAID principle to take over. The same applies for the tissue that is involved in throwing. A person who picks up a ball and throws at maximum effort has a much higher chance of injury than someone who on-ramped and went through preparation to throw maximally. Joint and tissue loading is a complex task to manage for all athletes and coaches. Due to this, please take heed before starting a generic weighted ball, lifting or training regimen that was not specifically designed for you and the make up of your body.

Should I do weighted balls before or after I’m done with long toss?

Obviously everyone has certain preferences and, more often than not, guys operate under the constraints of practice schedules so they may have to do their weighted ball work at a totally different part of the day. There are benefits to throwing overload balls before one begins long toss such as accelerating the warm up process, allowing the arm to lay back deeper into external rotation, and postactivation potention (PAP). PAP is the phenomenon by which the contractile history of skeletal muscles will subsequently affect that same muscle’s ability to produce and generate force. Basically, PAP is when a muscle’s ability to exert force is increased due to its previous contractions. Many guys enjoying doing their weighted ball routine before, but at the same token there is no downfall in doing your weighted ball routine after long toss. Those folks who do their routine after long toss allow themselves adequate time to walk their arm out, activate the necessary tissues and get the nervous system firing. Overall, it is really left up to personal preference and availability. If you end up looking for a world class long toss program, arguably the best program available is The Jaeger Sports' Program. I highly recommend following the link and checking it out.

Should I long toss and play catch with weighted balls?

Many of our guys long toss with the 4,5,6 and 7 oz weighted baseballs. Virtually everyone that I’ve talked to about long tossing with a weighted ball gives great feedback. Some guys just throw it at the beginning, some for the entire session. To limit your creativity as a pitcher and to say there is only one correct way to long toss, is foolish and wrong. Whether you like long toss or not, you should give it a shot and try stretching it out with a weighted ball of your choice. Also, if you’re training alone or without a throwing partner and need to simulate long toss into a net or wall, long tossing with a weighted plyoball is certainly a better option than not long tossing at all. I suggest long tossing with a weighted ball due to the biofeedback I have gotten and the positive feedback from others. For more information regarding weighted ball long toss, I highly recommend reviewing Driveline’s post on the same topic because I have not come across a better review of this topic than the linked article.

If I’m a bullpen guy, should I use weighted balls before I go in?

Here is Aroldis Chapman using a weighted ball in the bullpen.

Too often coaches neglect that bullpen arms are actual people who should adequately warm up before pitching. If you’re in that situation, (when you’re in the pen) and you see that hand spinning to “get hot” after you’ve been getting splinters in your rear end for seven innings, it may be a good idea to grab an overload ball to let your arm get into the necessary positions for you to be ready to let it eat when you get the call. Throwing the overload ball really helps you get going and warm up quickly before you pick up the baseball and spin a few before you go in. However, if you know your role is the 8th inning guy and you have a routine to be ready for that situation, then you should follow your routine whether that includes weighted balls or not. Yet, throwing weighted balls in the pen is being popularized more and more since guys are catching on and using them to their advantage.

Should I do weighted balls before, between or after I’m done throwing a bullpen?

Many pitchers use weighted balls before throwing a bullpen simply because they feel better, looser and faster before they get on the mound. Using overload balls pre-bullpen helps unlock ranges of motion, prepare the arm for the stresses that will soon ensue on a mound and allow a lighter and freer arm action. The biofeedback that our guys get from using overload balls pre-bullpen has been pretty remarkable across the board. Throwing weighted balls between pitches, during a bullpen, is popularly known as “blending”. Blending can be beneficial to draw on neuromuscular adaptations and the overlapping benefits of the contrast throwing with varying weights, intensities and techniques. Throwing weighted balls after a bullpen, and specifically doing drill work, as a cool down protocol is not a bad idea at all. In fact, it can be quite beneficial. I often find that guys who do weighted ball throws after bullpens end up doing it due to time constraints at practice, which is understandable. I have had guys who have to do their weighted ball training outside of the practice environment and on their own because their coaches or organizations were not in favor of weighted ball training.

What should I do if I want to train with weighted balls but I cannot do it at practice and do not have a training partner?

If you’re training under those kind of conditions you can always get a set of weighted baseballs or plyo balls and find a wall and/or net and get your work in there. You can simulate long toss or simulate flat ground throws with varying degrees of intensities and various drills. Traditionally, not having a throwing partner has been thought of as a disadvantage, but with proper programming and training implements, not having a consistent throwing partner can become a real advantage. Remote training can be incredibly beneficial for guys who have full access to sufficient partners and facilities, but it can also be great for guys looking to development on their own or do more than the standard population.

Should I use weighted balls when I return to throwing after extended time off?

Yes. When guys take time off from throwing they lose active ROM, not only in the shoulder and elbow but throughout the body. Active range of motion is when you move your joint through its ROM, whereas, passive range of motion is when someone else moves you through its ROM. Overload throws and constraint drills coupled with overload balls help organically create more ROM and begin the process of restoring the tissue and adaptations necessary to throw at high intensities. Considering that less stress is applied to the elbow (compared to a 5 oz baseball) when throwing an overload ball, it could be viewed as a nice intro for the body before breaking into more high impact training. Another pro to consider when returning to throwing is that overload balls help map a more efficient arm path. When beginning throwing it’s very important to ingrain proper movements and help shape the direction of the arm path through the delivery. Implementing overload balls, especially at the beginning of the return, can make all the difference when setting yourself up for longevity and durability. Different programs go through different phases of training throughout the year, yet most of our guys return to throwing with some element of weighted ball throws and the feedback has been great.

What are some ranges of motion that are affected from weighted ball throws?

Without diving too deep into the kinetics of throwing we can see that weighted ball training affects elbow extension and the loads and velocities it can handle, glenohumeral internal rotation, glenohumeral external rotation, humeral head retroversion, pronation of the forearm, and general scapular mobility which allows the scapulae to freely and more effectively move about the rib cage. Mind you, many other areas of the body that affect movement undergo adaptations and stress when throwing weighted balls. Soft tissue, ligaments, skeletal muscle structures, capsules, motor-neural pathways are all engaged and or recruited when throwing, so to think of ROM as only a few baseline measurements seems rather incomplete to me, since there are many accompanying factors that contribute to the ability to move well and the functionality of that movement.