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Weighted Balls-What you NEED to know!

One of the most frequent questions I get asked by coaches and parents is: “What are your thoughts on weighted balls?” This blog article will focus on my opinions as someone who has spent 30 years as a therapist treating shoulder and elbow issues, as well as a mom whose three boys all played baseball.  Let me begin with the fact that there is no consensus opinion in our industry. Much more research is needed on this topic.


As a physical therapist, I use both lighter and heavier weighted balls in rehab all the time. However, I use them for very specific purpose, this is to build load and capacity with throwers as they progress to 100% intensity of work in order to return to the field. I use shorter distance throwing, most often less than 15-25 feet. We use a variety of positions (tall kneeling, 1/2 kneeling, stationary throwing, and step and throw), a variety of mixed drills for acceleration/deceleration, and movement patterns from right to left, on the diagonal, from overhead and reverse. The types of throws are progressive and graded in nature. The whole time we are monitoring pain, feel, and form.


I also advise my throwers to use a smaller weighted balls (12-16oz) as part of their warm up routines. I especially like this for my high school players who may not have as much time to get “hot” as they do during the summer travel season. Players can easily pack one of these balls in their bag to take with them on the road.




When did weighted ball training start?

In the late '70 and early 80s with a throwing study with Dr. Coop DeRenne, a kinesiology professor and baseball coach from the University of Hawaii with Dr. Tom House started training with balls 20% lighter and heavier. Later on in 2008, they were looking at the use of heavier balls with a condition called GIRD (glenohumeral internal rotation deficiency), and one of the byproducts they found was that this had increased throwing velocity. From there, various weighted ball programs have hit the market and training centers.


What is considered a weighted ball?

In the purest definition a regular baseball is a weighted ball at 5oz. Most programs have underweight balls and overweight balls varying between 3 oz and 32 oz.


Who should not throw weighted balls?

      Here is my answer. No one under the age of 18 should be in a weighted ball program. PERIOD.  I would argue many freshman and sophomores in college should may away as well. Boys may not be skeletally mature up until the age of 25! Growth plates at the shoulder and elbow are vulnerable to increased stress and load. Most high school athletes who make the transition to collegiate ball put on average of 17# of lean muscle mass during the time. After that time, a weighted ball program may be indicated.


       Anyone with a dysfunctional throwing pattern should not be using weighted balls. Often youth and high school athletes demonstrate poor throwing mechanics. The worst thing to do is load a dysfunctional throwing pattern, this only adds to the problem. More time should be focused on developing improved movement patterns, location, and off-speed pitches.

What does the Research say?

An award-winning paper by one of my mentors, Mike Reinold, PT was published in 2018[1]. The study took 38 athletes, between the ages 13 and 18, and were randomly assigned to either a control group (which did a throwing program with only regular 5-oz baseballs), or a weighted-ball group (which had pitchers complete the same throwing program as the control group but with the additional weighted-ball training).

The weighted-ball program used balls weighing 4, 6, 16, and 32 ounces. Three drills were performed with each ball weight: Half Kneeling Throws, Rocker Throws, and Run and Gun.

  • Pitch velocity showed a statistically significant increase (3.3%) in the weighted ball group.

  • There was a statistically significant increase of 4.3% of shoulder external rotation (layback position) in the weighted ball group.

  • The overall injury rate was 24% in the experimental group (4/17, 2 athletes were removed for other injuries). Of those 4 injuries, two occurred during the training program and two in the season after training.

  • No pitchers from the control group were injured.

Some studies have shown gains with regard to strength, some were inconclusive with strength staying the same, or even in some cases decreasing.

So what does that mean?

Yes: weighted ball program increase strength over a 12-week time by 3.3%. However, a general plyometric weighted ball program increases strength by 4.2%


1.     Increased external rotation (layback position): At this point in time, we do not know the long-term effect of this on the growing athlete. What happens to the growth plate or the surrounding muscle tissue?  More layback is preferred for throwing and is correlated with greater velocities, but at what costs? External rotation in layback is a biomechanical inevitability with throwing.   It can become an issue if you don’t have the functional strength to stabilize the front of the shoulder in that position. Once that tissue is stretched out, there is no going back.


2.     24% injury rate. This study was performed by some of the best minds in the nation with regards to baseball performance. It was done with specific parameters and implementation under strict research guidelines. So how do those findings then transfer to the general population? Will your average dads or coaches be able to implement a program correctly.  The short and the long answer is NO. 


3.     Two participants were injured during the course of the study and 2 were injured in the following year so there is a short-term impact on injury and a long term in the following season.

Who might benefit?

I could make an argument that an athlete who is looking to go the next level (past college), who has exhausted all strength and mobility avenues, and who needs a velocity bump could benefit. They may benefit from a weighted ball program under the strict guidance of a well-trained S-C coach/pitching coordinator. That athlete has to understand the risk to benefit ratio (high reward / high risk). It should be periodized over the course of a year with careful monitoring of workload and recovery.


This program should be hyper-personalized to the athlete after a formal full body evaluation performed by a sports medicine professional and well as biomechanical assessment from the coaching side. Physical constraints and throwing disconnects must be addressed prior to starting and during a program.  Another mentor and friend of mine, Ron Wolforth from the Texas Baseball Ranch™, has his athletes train a minimum of 6 weeks throwing balls in his arm care program PRIOR to starting the weighted ball program. This means you have to have enough “off season” time to complete a weighted ball program – this is a longer process than most high school and college programs have available where they can work with their players. Arm health is then monitored on a DAILY basis and adjustments are made on the spot.


Other problems I see

Weighted balls are tools, just like bats, gloves, and a variety of other baseball related products. Companies market and sell them just like any other product promising "a desired result". Selling products improves the bottom line.


The internet is a double-edged sword with information. Many athletes, parents, and coaches use it for improving their baseball knowledge, adding a drill, etc.  Weighted ball marketing campaigns show us “teasers of activities’’ you can do with their program. Many (athletes, parents, and coaches) will think "I like that drill" and put it in their training regimen. That particular exercise might be a small part of total program. In the selling of the product, we are not privy to that exercise’s actual intentions (warm up/cool down), what part of the program it is to be implemented (week 1 or week 8), the number of reps/rest breaks, and when in the training cycle it should be performed in relation to the season. It’s like picking out the perfect Christmas tree in deep forest at night during the summer.


A well-known baseball company clearly states on their weighted ball page, these players also underwent an “evaluation by a trained medical professional prior to the initiation of the program”. I have not met one player to date that underwent an evaluation prior to starting a weighted ball program: unfortunately, I have evaluated many after sustaining an injury from a weighted ball program. 


Some of the important questions when evaluating a player would be:


·        Do they have sufficient shoulder motion such external rotation and internal rotation motion?

·        Are they lacking scapular upward rotation?

·        Can they get their hands overhead (flexion) without compensating in the lower back segments?

·        Do they have sufficient cervical rotation?

·        Do they have a history of pain or injury?

·        How well do they throw off the mound?


I have a friend who paid $500 to a reputable organization for a 12-week weighted ball program for his son. No questions were asked regarding his son’s age, weight, previous injuries, and or mobility/strength profile. To me that’s unacceptable.


Other Considerations for Weighted Ball Training

  • Pain

No pain can be present before the initiation of a weighted ball program. Many players will lie about pain. Many believe there is something magical about weighted balls and they don’t want to miss participating in a program.  Pain of ANY kind is an ABSOLUTE CONTRAINDICATION to a weighted ball program.

  • Changing weighted balls during a session

When you pick up a heavier ball, your brain says – “this is heavy” – your body knows and says “I might need to adjust my movement pattern and be more cautious”. However, when switching to a lighter ball, you don’t have that same level of control. It is actually much easier to get hurt throwing a lighter ball due to the quick acceleration of movement. I would also add that switching between light and heavy balls creates chaos in the brain and the musculoskeletal system; younger kids don’t’ have the knowledge and body control. They have a hard time adapting to these stresses and thus increase the potential for injury.  As you increase the weight of the ball, you slow down the arm action. The more a ball weighs, the less you can accelerate it.  Less acceleration means less force on the ligaments and tendons.  In other words, there is actually less force on the ligaments and tendons with a heavier ball (to a certain point).


  • Programming Problems

A weighted ball training day should be considered as "heavy" when cycling workloads. How will you integrate this in a players overall training? Are they throwing a bull pen right before or after these training days? Are they utilizing proper recovery techniques? Are they weightlifting in addition to throwing? All of these training variable need to be monitored.


AND Lastly…

 We know its dangerous but we still choose to do it! A study by Cross et all ’22 looked at perception of injury risk with 376 baseball players between the ages of 17-39. 71% had used weighted ball, most often 3-5x/week.

-71% (267/377) reported the use of weighted balls.

-75% of those (199/267) thought it made them a better player.

HOWEVER, overall 73% (275/377) thought weighted balls were a risk for injury

-17% (46/267) attributed their injury to suing weighted baseballs

-Overall, 72% +/- 30% said the likelihood of future weighted baseball use

At the end of the day, weighted baseball are not a one size fits all programming. The program should be tailored to the individual goals of the player, consider their current and past arm health, under the guidance of a highly trained professionals. Our youth and high school players should focus on mobility, strength, movement patterns, throwing drills and recovery first.

Athletic Edge and Wellness, Illinois Baseball Edge and 1Top Prospect in Algonquin are your professional throwing partners in baseball/softball performance and arm care: We offer private and team instruction, velocity enhancement, command sessions, throwing form, coaching clinics, Flightscope video assessment, data analytics, physical therapy, performance therapy, normatech recovery, and collegiate recruiting under one roof. Come experience the difference from our pros in the field.

[1] Reinold: Sports Health ‘18


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